[bolger] Re: Mast anxiety (table of wood properties)
Lincoln Ross wrote:
take in all the info. Might have to print landscape instead of portrait
mode.
djb
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> I'll have to go back to the table as I only recall seeing the firstI found saving as html file and viewing in my browser made it easier to
> three items on it. (Only printed out 3)
take in all the info. Might have to print landscape instead of portrait
mode.
djb
>--
>
> -----------------------------------------------------------------------
>
>
> eGroups.com Home:http://www.egroups.com/group/bolger
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Quasi esoteric musical instruments
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I think a modification of the Ohio pound net sharpie sail (see Chapelle's
American Small Sailing Craft or Parker's The Sharpie Book) would make a
good sail for a Bolger boat. The idea would be to keep the sprit boom, but
make a quadrilateral sail shaped somewhat like a gaff sail with topsail
combined. A couple of light wooden battens bolted though the sail would
extend the "peak". The battens would be lashed to a mast hoop, or even a
sail track car. A very nice thing about this setup is that the mast and
sprit are exactly the same as for the original rig, and no extra strings
are needed. A Micro could carry the "pound net" sail when light winds are
expected, or the standard leg o' mutton when you think there's going to be
more wind (a row or two of reef points should be added to the pound net
sharpie sail just in case things don't turn out as you expected!). Micro's
mizzen would take care of any shift in the center of lateral effort.
I've put a drawing of the sort of sail I'm thinking of here:
http://www.cyber-dyne.com/~jkohnen/images/ErieSail.gif
American Small Sailing Craft or Parker's The Sharpie Book) would make a
good sail for a Bolger boat. The idea would be to keep the sprit boom, but
make a quadrilateral sail shaped somewhat like a gaff sail with topsail
combined. A couple of light wooden battens bolted though the sail would
extend the "peak". The battens would be lashed to a mast hoop, or even a
sail track car. A very nice thing about this setup is that the mast and
sprit are exactly the same as for the original rig, and no extra strings
are needed. A Micro could carry the "pound net" sail when light winds are
expected, or the standard leg o' mutton when you think there's going to be
more wind (a row or two of reef points should be added to the pound net
sharpie sail just in case things don't turn out as you expected!). Micro's
mizzen would take care of any shift in the center of lateral effort.
I've put a drawing of the sort of sail I'm thinking of here:
http://www.cyber-dyne.com/~jkohnen/images/ErieSail.gif
On Fri, 03 Mar 2000 19:59:48 -0500, you wrote:
> There are plenty of ways to use lacing, or even hoops instead of track on a
> jib-headed sail!
>
> Peter
>
>
>
> >Right on the target, Peter! I'm thinking very seriously about that
> >possibility! I think that a gaff main would also be prettier, other
> >than handier, and would allow to get rid of the sail track! Anybody
> >fron PCB&F reading this thread?
--
John <jkohnen@...>
http://www.cyber-dyne.com/~jkohnen/nautical.html
One must have a heart of stone to read the death of Little Nell by
Dickens without laughing. <Oscar Wilde>
"frank san miguel" <sanm-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3447
elastic. If you want to know how far you can bend it, that's another
question. In that case you need to know the stress at failure
(strength). For instance, Aluminum has elastic modulus around
10,000,000, steel 30,000,000. If you have a low elastic modulus and
high strength, you can bend a long way.
probably nice to do well on this test.
I'll have to go back to the table as I only recall seeing the first
three items on it. (Only printed out 3)
original article:http://www.egroups.com/group/bolger/?start=3447
> More details on parameters from my table:Actually, I think you're off here. The higher the number, the less
> snip
>
> 2. Static Bending: Modulus of elasticity (1000 lb/sq in): This
> describes how elastic the material is - how much bending the wood can
> take and still spring back to its original shape. The bigger the
> number the more elastic the wood. This shouldn't be confused with
> force required to bend the wood. snip
elastic. If you want to know how far you can bend it, that's another
question. In that case you need to know the stress at failure
(strength). For instance, Aluminum has elastic modulus around
10,000,000, steel 30,000,000. If you have a low elastic modulus and
high strength, you can bend a long way.
>Isn't this stress at failure?
> 3. Static Bending: Modulus of rupture (lb/sq in): This measures force
> per unit deflection of the beam after you have passed the elastic
> limit.
>snipthis has a higher strain rate than a mast would be likely to see, but
> 5. Impact bending,
probably nice to do well on this test.
I'll have to go back to the table as I only recall seeing the first
three items on it. (Only printed out 3)
More details on parameters from my table:
I am stretching my memory of mechanics, which is why I caveated my
original conclusions, but I'll give it a try. Someone can correct me
if I make a mistake.
The people who made the chart performed destructive testing using
"blanks" of different species of wood. All of the blanks are 2"x2" in
cross section with a 12 percent moisture content.
1. Density at 12% moisture content (lb/cu ft): This is weight per given
unit volume.
2. Static Bending: Modulus of elasticity (1000 lb/sq in): This
describes how elastic the material is - how much bending the wood can
take and still spring back to its original shape. The bigger the
number the more elastic the wood. This shouldn't be confused with
force required to bend the wood. Hardwoods are generally more elastic
than soft woods, but it takes more force to bend them. I changed my
mind and now think that modulus of elasticity is the second best
measure for an unstayed, sprit-boomed mast. Elastic wood won't break
as easily under heavy dynamic load and will spring back to straight
more readily.
3. Static Bending: Modulus of rupture (lb/sq in): This measures force
per unit deflection of the beam after you have passed the elastic
limit. Passing the elastic limit means you've bent the wood so far
that it won't spring back. I am pretty sure it isn't useful for our
mast problem. I originally though this was a good measure for the mast
problem, but I take it back now.
4. Tensile strength perpendicular to grain. They take the blank and
pull it apart cross grain until it breaks. Doesn't seem too relevant
to me for analyzing masts, but I put it in anyway.
5. Impact bending, height of drop in inches for failure w/ 50-lb
hammer. They take the blank and place it in a jig (perhaps a big
vise). Then they drop a 50-lb weight on the end and drop it from
different heights until the wood breaks (they probably put a new blank
in for each height). In the case of unstayed masts this seems like the
best measure of mast strength. The greatest shear force on an
unstayed mast will be at the mast partner and a break there will likely
be caused by a "dynamic" load like a sudden gust or running into a sand
bar. Since the number is in inches, it is most interesting for
comparing different woods.
Frank
"edward haile" <ewhail-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3441
I am stretching my memory of mechanics, which is why I caveated my
original conclusions, but I'll give it a try. Someone can correct me
if I make a mistake.
The people who made the chart performed destructive testing using
"blanks" of different species of wood. All of the blanks are 2"x2" in
cross section with a 12 percent moisture content.
1. Density at 12% moisture content (lb/cu ft): This is weight per given
unit volume.
2. Static Bending: Modulus of elasticity (1000 lb/sq in): This
describes how elastic the material is - how much bending the wood can
take and still spring back to its original shape. The bigger the
number the more elastic the wood. This shouldn't be confused with
force required to bend the wood. Hardwoods are generally more elastic
than soft woods, but it takes more force to bend them. I changed my
mind and now think that modulus of elasticity is the second best
measure for an unstayed, sprit-boomed mast. Elastic wood won't break
as easily under heavy dynamic load and will spring back to straight
more readily.
3. Static Bending: Modulus of rupture (lb/sq in): This measures force
per unit deflection of the beam after you have passed the elastic
limit. Passing the elastic limit means you've bent the wood so far
that it won't spring back. I am pretty sure it isn't useful for our
mast problem. I originally though this was a good measure for the mast
problem, but I take it back now.
4. Tensile strength perpendicular to grain. They take the blank and
pull it apart cross grain until it breaks. Doesn't seem too relevant
to me for analyzing masts, but I put it in anyway.
5. Impact bending, height of drop in inches for failure w/ 50-lb
hammer. They take the blank and place it in a jig (perhaps a big
vise). Then they drop a 50-lb weight on the end and drop it from
different heights until the wood breaks (they probably put a new blank
in for each height). In the case of unstayed masts this seems like the
best measure of mast strength. The greatest shear force on an
unstayed mast will be at the mast partner and a break there will likely
be caused by a "dynamic" load like a sudden gust or running into a sand
bar. Since the number is in inches, it is most interesting for
comparing different woods.
Frank
"edward haile" <ewhail-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3441
> To Frank San Miguel,explain
>
> Thanks for the chart. I have copied it into my boat file. But please
> the parameters.
>
> Ed Haile
>
>
> ______________________________________________________
"matthew long" wrote:original article:
snip Conventional aircraft wisdom says that Sitka spruce is the strongest commonly available wood for spars and the like per unit weight (NOT per unit cross-sectional area). That's just because they're afraid to carve an airplane out of a big balsa log. Someone earlier in this thread was asking what all the numbers meant in the table. WHat a huge topic! However, modulus of elasticity is how stiff the wood is (how much does your mast bend), modulus of rupture is strength. If the density is less, you can increase the mast diameter to make up for any reduced stiffness or strength. Strength goes up as the cube of the mast dia, stiffness as the fourth power, weight as the square of dia. So you see a light wood can come out ahead if you don't mind making the mast a little fatter. By these standards, white pine looks pretty good. If you don't mind a mast 2.5X the size that doesn't like to get wet, get balsa!
As someone who came to boatbuilding as a frustrated (time and money)
aircraft homebuilder, I can second your conclusions. Conventional
aircraft wisdom says that Sitka spruce is the strongest commonly
available wood for spars and the like per unit weight (NOT per unit
cross-sectional area). Most wooden aircraft are designed to use
aircraft-grade Sitka spruce for most non-plywood applications.
There are other acceptable aircraft building woods, such as Douglas
fir, but the usual practice is to build to the same dimensions as Sitka
spruce, gaining increased strength but with a substantial (for
aircraft) weight penalty.
Basically, I would second Frank's conclusion that the quality of the
wood, gluing, assembly, etc. is the key to adequate strength and long
life (aircraft spruce is a joy to behold). Substituting other common
woods is a non-event for our purposes, as long as the wood is not
excessively rot-prone.
My 2¢, yet again!
Matthew
"frank san miguel" wrote:original article:
To Frank San Miguel,
Thanks for the chart. I have copied it into my boat file. But please explain
the parameters.
Ed Haile
______________________________________________________
Thanks for the chart. I have copied it into my boat file. But please explain
the parameters.
Ed Haile
______________________________________________________
This thread piqued my interest, so I did a little more research using Mark's Handbook and here are my conclusions: I looked at the following wood properties from a table of experimental results:
I don't know for sure which of these properties is most important in selecting a mast material, but I'd guess number one is impact bending, followed by static bending modulus of rupture. There were 10 different woods in the table that I have seen in discussions about mast materials:
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Frank,
I have a little experience with redwood as a soundboard for musical
instruments, as a substitute for sitka spruce. It works (a brighter
sound for what it's worth) but I did find it to be more brittle than
spruce. Another two cents.
djb
Frank San Miguel wrote:
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Quasi esoteric musical instruments
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I have a little experience with redwood as a soundboard for musical
instruments, as a substitute for sitka spruce. It works (a brighter
sound for what it's worth) but I did find it to be more brittle than
spruce. Another two cents.
djb
Frank San Miguel wrote:
>--
>
> I just made a 21.5' mast of grade B redwood for my 15' sharpie. In my
> local yards here in Colorado, all of the long pine 2x stock was very
> knotty and twisty. The redwood was the only straight stuff I could
> find. I looked it up in Marks Engineering Handbook and found that
> redwood has a similar toughness and loading strength, but I honestly
> don't know whether it will be good enough. I am pretty sure that
> redwood is lighter and it is much more rot resistant than yellow pine.
> I spent about $70 on the wood and 17 hours scarfing, cutting and
> gluing. So I hope it doesn't break!
>
> Frank
>
> francisco =?iso-8859-1?q?ram=edrez?=astrolabi-@...wrote:
> original article:http://www.egroups.com/group/bolger/?start=3398
> > In Classic Boat magazine, issue #112 (oct 997), there is a really nice
> > "old fashioned" italian gaff-rigged catboat, with glassifbre mast,
> > called Difference. In the article, you can reed: "The mast, boom and
> > gaff are also glassfibre, centrifugally turned, making them light and
> > strong".
> >
> > In issue #106, in an article call "making a mast" (by Larry Pardey):
> > "I have seen spars of spruce, douglas fir, pitchpine, mahogany,
> hemlock,
> > ash, cedar, and even teak. The wood chosen should be readily avaiable,
> > easily worked and, most importantly, take glue well. My firs choice
> > would be spruce or Douglas fir (Oregon pine). Douglas fir is stronger
> > and more rot-resistant than spruce but heavier per cubic foot. If you
> > are weight-conscious and can't get spruce, check with a designer. You
> > can probably use a 20 per cent thinner mast wall and still end up
> with a
> > similar weight-to-strength ratio"
> >
> > Regards
> >
> > Francisco
>
>
> -----------------------------------------------------------------------
>
>
> eGroups.com Home:http://www.egroups.com/group/bolger
> www.egroups.com - Simplifying group communications
SOME CLICKS THAT COUNT!!
Feed someone.
http://www.thehungersite.com/
Save a little rain forest.
http://rainforest.care2.com/front.html/player12296
Simplicity Boats (& mirror sites)
http://members.tripod.com/simplicityboats/index.html
http://members.xoom.com/simpleboats/index.html
Here's my latest boat:
http://members.tripod.com/simplicityboats/featherwind.html
http://members.xoom.com/simpleboats/featherwind.html
Quasi esoteric musical instruments
http://unicornstrings.com
From: "Robert N. Lundy" <robert@...>
To: <bolger@egroups.com>
Date sent: Fri, 3 Mar 2000 22:33:42 -0500
Send reply to:bolger@egroups.com
Subject: [bolger] Re: Router and boltrope (was mast anxiety)
Hi Robert,
This used to be the way of doing luff tracks on small racing dinghys
before aluminium masts came along.
You have to make the mast a little wider fore and aft at the bottom,
so the groove exits vertically. Running the groove out at an angle
will jam the sail when you pull it up.
I was a little worried that this mastmight have been too big/long for
this system (too much friction), but the sail goes up and down
easily. Best not to make the rear slit down the mast too wide -
just enough for the reinforced parts of the luff to pass up.
Good on you for the TNZ shirt. But thank God it's over. Our lives
here have been totally dominated by the cup until today. Our one
extravagance was a day out on a charter boat for the 4th race, and
no wind! Enjoyed the wine and food though, and watched with
fascination a lady who ran for the rail and decorated the topsides of
the boat! Just as fascinating were the people around her, who ran
to the other end of the boat from her, and gazed steadfastly out to
sea.....avoiding auto-suggestion I guess!
Don
To: <bolger@egroups.com>
Date sent: Fri, 3 Mar 2000 22:33:42 -0500
Send reply to:bolger@egroups.com
Subject: [bolger] Re: Router and boltrope (was mast anxiety)
Hi Robert,
This used to be the way of doing luff tracks on small racing dinghys
before aluminium masts came along.
You have to make the mast a little wider fore and aft at the bottom,
so the groove exits vertically. Running the groove out at an angle
will jam the sail when you pull it up.
I was a little worried that this mastmight have been too big/long for
this system (too much friction), but the sail goes up and down
easily. Best not to make the rear slit down the mast too wide -
just enough for the reinforced parts of the luff to pass up.
Good on you for the TNZ shirt. But thank God it's over. Our lives
here have been totally dominated by the cup until today. Our one
extravagance was a day out on a charter boat for the 4th race, and
no wind! Enjoyed the wine and food though, and watched with
fascination a lady who ran for the rail and decorated the topsides of
the boat! Just as fascinating were the people around her, who ran
to the other end of the boat from her, and gazed steadfastly out to
sea.....avoiding auto-suggestion I guess!
Don
> You know, I've thought about thsi since I bought my Micro Plansback in
> 1990. I've never heard of or seen it done, thanks for the tip. I always
> thought any design including sail track could be done this way with a router
> and the appropriate bit.
>
> BTW, to you (Don/Oink), Foster, et al, absolutely a fabulous A/C defense.
> My Team NZ shirt and hat arrived the day after the cup was won (your boats
> are faster than your shipping-six weeks to get here). Wearing them proudly
> in Florida with thoughts of what 2002-3 will be like. Lots of used boats
> for use in the NZ conditions might make for a huge challenger fleet. On top
> of that, after the AUS Sydney Olympics, the aussies (with funds) should be
> calling with blood in their eyes, having distinguished themselves pretty
> well with San Diego boats this year. Could be an even better show.
>
> Robert, after quaffing significant yellow beverages at the marina tonight,
> on the shores of Tampa Bay, still doing Windsprint gunwales....
>
> Robert & Amy Lundy
> St. Petersburg, fla.
>robert@...
>amy@...
>
>
> > -----Original Message-----
> > From:oink@...[mailto:oink@...]
> > Sent: March 03, 2000 10:05 PM
> > To:bolger@egroups.com
> > Subject: [bolger] Re: Gaff main on Micro? (was Mast anxiety)
> >
> >
> >
> > > Right on the target, Peter! I'm thinking very seriously about that
> > > possibility! I think that a gaff main would also be prettier, other
> > > than handier, and would allow to get rid of the sail track! Anybody
> > > fron PCB&F reading this thread?
> > >
> > > Best, Pippo
> >
> > Pippo, I didn't use an external metal track as shown on the Micro
> > plans for mainsail luff. I tried hard to find it, but the old-fashioned
> > low-tech hardware is just not available in NZ anymore.
> > So I just got a router and grooved both sides of the timber to make
> > a luff groove when glued together, and ordered the sail with a luff
> > boltrope, just like a dinghy mast.
> > It works perfectly.
> > Don
> >
> > ------------------------------------------------------------------------
> > GET A NEXTCARD VISA, in 30 seconds! Get rates
> > as low as 0.0% Intro APR and no hidden fees.
> > Apply NOW!
> >http://click.egroups.com/1/975/5/_/3457/_/952139294/
> >
> > -- Talk to your group with your own voice!
> > --http://www.egroups.com/VoiceChatPage?listName=bolger&m=1
> >
> >
>
>
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>
>
Hi Pippo,
You may wish to consider building the mainmast,as per plan,just so
that you can keep that little 1/2 inch hollow in the center.I used it
to run my wires up the inside for the masthead 360 degree white light.
Also,while I agree that the gaff rig looks pretty,it can also be a
wonderful source of some rather inspired dancing around in the
cockpit,on a windy day,with lots of waves,as you attempt to lower the
main and have the boom "sweeping the deck" while the gaff is trying to
decapitate the dancer.The Micro is still a small boat and will
rock-n-roll with each and every wave!But then again,I have no
experience with the gaff rig,only that lovely sprit boom on the
Micro.Therefore any"tricks" used to tame the unburdened gaff rig escape
me.
Sincerely,
Peter Lenihan,still enjoying bottled water despite evil thoughts for
something stronger,if not tastier,on the frozen shores of the
St.Lawrence......
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3396
You may wish to consider building the mainmast,as per plan,just so
that you can keep that little 1/2 inch hollow in the center.I used it
to run my wires up the inside for the masthead 360 degree white light.
Also,while I agree that the gaff rig looks pretty,it can also be a
wonderful source of some rather inspired dancing around in the
cockpit,on a windy day,with lots of waves,as you attempt to lower the
main and have the boom "sweeping the deck" while the gaff is trying to
decapitate the dancer.The Micro is still a small boat and will
rock-n-roll with each and every wave!But then again,I have no
experience with the gaff rig,only that lovely sprit boom on the
Micro.Therefore any"tricks" used to tame the unburdened gaff rig escape
me.
Sincerely,
Peter Lenihan,still enjoying bottled water despite evil thoughts for
something stronger,if not tastier,on the frozen shores of the
St.Lawrence......
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3396
> Peternothing
>
> "peter vanderwaart" <pvander-@...> wrote:
>
> > Is the Micro mast design solid, or Mr. Bolger's usual '4 stave round
> > mast'?
>
> It's a tapered octagonal section above the heel, and a tapered square
> section below. I agree with you that a 1/2" square hollow means
> in terms of weight, and in fact my idea is to glue two full lenght
> boards (9.0x4.5 cm^2 each) just to avoid warping.
>
> > Think how handy the mast of a Micro mast would be if it had a gaff
> rig.
>
> Right on the target, Peter! I'm thinking very seriously about that
> possibility! I think that a gaff main would also be prettier, other
> than handier, and would allow to get rid of the sail track! Anybody
> fron PCB&F reading this thread?
>
> Best, Pippo
>
You know, I've thought about thsi since I bought my Micro Plans back in
1990. I've never heard of or seen it done, thanks for the tip. I always
thought any design including sail track could be done this way with a router
and the appropriate bit.
BTW, to you (Don/Oink), Foster, et al, absolutely a fabulous A/C defense.
My Team NZ shirt and hat arrived the day after the cup was won (your boats
are faster than your shipping-six weeks to get here). Wearing them proudly
in Florida with thoughts of what 2002-3 will be like. Lots of used boats
for use in the NZ conditions might make for a huge challenger fleet. On top
of that, after the AUS Sydney Olympics, the aussies (with funds) should be
calling with blood in their eyes, having distinguished themselves pretty
well with San Diego boats this year. Could be an even better show.
Robert, after quaffing significant yellow beverages at the marina tonight,
on the shores of Tampa Bay, still doing Windsprint gunwales....
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
1990. I've never heard of or seen it done, thanks for the tip. I always
thought any design including sail track could be done this way with a router
and the appropriate bit.
BTW, to you (Don/Oink), Foster, et al, absolutely a fabulous A/C defense.
My Team NZ shirt and hat arrived the day after the cup was won (your boats
are faster than your shipping-six weeks to get here). Wearing them proudly
in Florida with thoughts of what 2002-3 will be like. Lots of used boats
for use in the NZ conditions might make for a huge challenger fleet. On top
of that, after the AUS Sydney Olympics, the aussies (with funds) should be
calling with blood in their eyes, having distinguished themselves pretty
well with San Diego boats this year. Could be an even better show.
Robert, after quaffing significant yellow beverages at the marina tonight,
on the shores of Tampa Bay, still doing Windsprint gunwales....
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
> -----Original Message-----
> From:oink@...[mailto:oink@...]
> Sent: March 03, 2000 10:05 PM
> To:bolger@egroups.com
> Subject: [bolger] Re: Gaff main on Micro? (was Mast anxiety)
>
>
>
> > Right on the target, Peter! I'm thinking very seriously about that
> > possibility! I think that a gaff main would also be prettier, other
> > than handier, and would allow to get rid of the sail track! Anybody
> > fron PCB&F reading this thread?
> >
> > Best, Pippo
>
> Pippo, I didn't use an external metal track as shown on the Micro
> plans for mainsail luff. I tried hard to find it, but the old-fashioned
> low-tech hardware is just not available in NZ anymore.
> So I just got a router and grooved both sides of the timber to make
> a luff groove when glued together, and ordered the sail with a luff
> boltrope, just like a dinghy mast.
> It works perfectly.
> Don
>
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>
> Right on the target, Peter! I'm thinking very seriously about thatPippo, I didn't use an external metal track as shown on the Micro
> possibility! I think that a gaff main would also be prettier, other
> than handier, and would allow to get rid of the sail track! Anybody
> fron PCB&F reading this thread?
>
> Best, Pippo
plans for mainsail luff. I tried hard to find it, but the old-fashioned
low-tech hardware is just not available in NZ anymore.
So I just got a router and grooved both sides of the timber to make
a luff groove when glued together, and ordered the sail with a luff
boltrope, just like a dinghy mast.
It works perfectly.
Don
Stan,
You have piqued my interest here. I am just about to glue up the
main mast and start my search for sail track. I am planning on sail
track for both the mizzen and main.
Tell me a little more about the sails. How old? Who made them? and
how much you want. Where are you located? How are they rigged? bolt
ropes? double seamed edges? etc. . .]
I tried your email address and the message came back. Please double
check your email address or contact me atdjost@...
Fraternally Yours,
David Jost Ashland, MA
stan muller <smulle-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3402
You have piqued my interest here. I am just about to glue up the
main mast and start my search for sail track. I am planning on sail
track for both the mizzen and main.
Tell me a little more about the sails. How old? Who made them? and
how much you want. Where are you located? How are they rigged? bolt
ropes? double seamed edges? etc. . .]
I tried your email address and the message came back. Please double
check your email address or contact me atdjost@...
Fraternally Yours,
David Jost Ashland, MA
stan muller <smulle-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3402
> Hi All;masts
> If there is a stateside builder of the Micro, I still have the
> and all the rigging, including new sails that will not be used on myone
> Micro- Navigator- Birdwatcher- Tug, the Snow Goose. There has been
> interest shown in the sails, but I would rather get rid of it all at
> time if possible. the main mast is made of three layers of sitkaspruce,
> and is tapered but still has a square cross section as it has not hadturned
> the corners planed off yet. If anyone is within hauling distance and
> interested, drop me an email. It's all of no use to me, and I'll make
> you, "such a deal!" ;-)
>
> Thanks, Stan, stiff and sore from trying to do boat work on what
> out to be a cool wet day.
Giuseppe,
On Cape Cod, I have had the opportunity to sail a lot of Catboats.
chekc out the article on the Crosby Cats in this months Wooden Boat
magazine. This is a great rig for a beamy boat such as a cat in that
it provides a lot of drive. There are some real disadvantages
depending on your sailing conditions.
1. This rig is easily overpowered. Reef early and often. It is very
difficult to reef in a pitching sea with that gaff swinging around.
2. The booms tend to be long in proportion to the gaffs. They can be
tripped up in a following sea or on a beam reach. In smaller bays and
shallow seas this is not a problem in that the seas do not get terribly
high, however in areas where the swell can get rather large and long I
have actually seen a Catboat get tripped on its own boom. Not suitable
for offshore passages (long boom types such as the Crosby).
3. Jibing is tricky. Head up a little to trim in, then jibe. This
helps control the gaff.
I think Micro's rig is pretty well thought out. I have visions of
sitting in Edgartown harbor with the sails furled up and bagged (still
on the tracks) and a clear clean uncluttered cockpit to relax in. The
sprits will make great boom tents. There is this seafood restaurant
not far from the docks. . . .
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3396
On Cape Cod, I have had the opportunity to sail a lot of Catboats.
chekc out the article on the Crosby Cats in this months Wooden Boat
magazine. This is a great rig for a beamy boat such as a cat in that
it provides a lot of drive. There are some real disadvantages
depending on your sailing conditions.
1. This rig is easily overpowered. Reef early and often. It is very
difficult to reef in a pitching sea with that gaff swinging around.
2. The booms tend to be long in proportion to the gaffs. They can be
tripped up in a following sea or on a beam reach. In smaller bays and
shallow seas this is not a problem in that the seas do not get terribly
high, however in areas where the swell can get rather large and long I
have actually seen a Catboat get tripped on its own boom. Not suitable
for offshore passages (long boom types such as the Crosby).
3. Jibing is tricky. Head up a little to trim in, then jibe. This
helps control the gaff.
I think Micro's rig is pretty well thought out. I have visions of
sitting in Edgartown harbor with the sails furled up and bagged (still
on the tracks) and a clear clean uncluttered cockpit to relax in. The
sprits will make great boom tents. There is this seafood restaurant
not far from the docks. . . .
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3396
> Peternothing
>
> "peter vanderwaart" <pvander-@...> wrote:
>
> > Is the Micro mast design solid, or Mr. Bolger's usual '4 stave round
> > mast'?
>
> It's a tapered octagonal section above the heel, and a tapered square
> section below. I agree with you that a 1/2" square hollow means
> in terms of weight, and in fact my idea is to glue two full lenght
> boards (9.0x4.5 cm^2 each) just to avoid warping.
>
> > Think how handy the mast of a Micro mast would be if it had a gaff
> rig.
>
> Right on the target, Peter! I'm thinking very seriously about that
> possibility! I think that a gaff main would also be prettier, other
> than handier, and would allow to get rid of the sail track! Anybody
> fron PCB&F reading this thread?
>
> Best, Pippo
>
Hi All;
If there is a stateside builder of the Micro, I still have the masts
and all the rigging, including new sails that will not be used on my
Micro- Navigator- Birdwatcher- Tug, the Snow Goose. There has been
interest shown in the sails, but I would rather get rid of it all at one
time if possible. the main mast is made of three layers of sitka spruce,
and is tapered but still has a square cross section as it has not had
the corners planed off yet. If anyone is within hauling distance and
interested, drop me an email. It's all of no use to me, and I'll make
you, "such a deal!" ;-)
Thanks, Stan, stiff and sore from trying to do boat work on what turned
out to be a cool wet day.
If there is a stateside builder of the Micro, I still have the masts
and all the rigging, including new sails that will not be used on my
Micro- Navigator- Birdwatcher- Tug, the Snow Goose. There has been
interest shown in the sails, but I would rather get rid of it all at one
time if possible. the main mast is made of three layers of sitka spruce,
and is tapered but still has a square cross section as it has not had
the corners planed off yet. If anyone is within hauling distance and
interested, drop me an email. It's all of no use to me, and I'll make
you, "such a deal!" ;-)
Thanks, Stan, stiff and sore from trying to do boat work on what turned
out to be a cool wet day.
There are plenty of ways to use lacing, or even hoops instead of track on a
jib-headed sail!
Peter
jib-headed sail!
Peter
>Right on the target, Peter! I'm thinking very seriously about that
>possibility! I think that a gaff main would also be prettier, other
>than handier, and would allow to get rid of the sail track! Anybody
>fron PCB&F reading this thread?
I just made a 21.5' mast of grade B redwood for my 15' sharpie. In my
local yards here in Colorado, all of the long pine 2x stock was very
knotty and twisty. The redwood was the only straight stuff I could
find. I looked it up in Marks Engineering Handbook and found that
redwood has a similar toughness and loading strength, but I honestly
don't know whether it will be good enough. I am pretty sure that
redwood is lighter and it is much more rot resistant than yellow pine.
I spent about $70 on the wood and 17 hours scarfing, cutting and
gluing. So I hope it doesn't break!
Frank
francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3398
local yards here in Colorado, all of the long pine 2x stock was very
knotty and twisty. The redwood was the only straight stuff I could
find. I looked it up in Marks Engineering Handbook and found that
redwood has a similar toughness and loading strength, but I honestly
don't know whether it will be good enough. I am pretty sure that
redwood is lighter and it is much more rot resistant than yellow pine.
I spent about $70 on the wood and 17 hours scarfing, cutting and
gluing. So I hope it doesn't break!
Frank
francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3398
> In Classic Boat magazine, issue #112 (oct 997), there is a really nicehemlock,
> "old fashioned" italian gaff-rigged catboat, with glassifbre mast,
> called Difference. In the article, you can reed: "The mast, boom and
> gaff are also glassfibre, centrifugally turned, making them light and
> strong".
>
> In issue #106, in an article call "making a mast" (by Larry Pardey):
> "I have seen spars of spruce, douglas fir, pitchpine, mahogany,
> ash, cedar, and even teak. The wood chosen should be readily avaiable,with a
> easily worked and, most importantly, take glue well. My firs choice
> would be spruce or Douglas fir (Oregon pine). Douglas fir is stronger
> and more rot-resistant than spruce but heavier per cubic foot. If you
> are weight-conscious and can't get spruce, check with a designer. You
> can probably use a 20 per cent thinner mast wall and still end up
> similar weight-to-strength ratio"
>
> Regards
>
> Francisco
Matthew, catched this just before going to sleep (yawn...)
"matthew long" <owlnmol-@...> wrote:
plans. However, this consideration would apply also to the enlarged rig
mentioned by Francisco. By the way, who in the list was aware of that
addition to the Micro plans?
the dollar?
Best
Pippo
"matthew long" <owlnmol-@...> wrote:
> Seriously, the Micro has stood the test of time with a fine reputationYou're right, as most probably I'll end up with doing everything as per
> and many boats built. I love the daydreaming and "what if..." as much
> as anybody, but maybe you ought to build it stock and see how you like
> it before making any major mods?
plans. However, this consideration would apply also to the enlarged rig
mentioned by Francisco. By the way, who in the list was aware of that
addition to the Micro plans?
> Just my 2 cents (200 lire?), mind you,Is the Euro (and the lira with it) falling so rapidly with respect to
the dollar?
Best
Pippo
In Classic Boat magazine, issue #112 (oct 997), there is a really nice
"old fashioned" italian gaff-rigged catboat, with glassifbre mast,
called Difference. In the article, you can reed: "The mast, boom and
gaff are also glassfibre, centrifugally turned, making them light and
strong".
In issue #106, in an article call "making a mast" (by Larry Pardey):
"I have seen spars of spruce, douglas fir, pitchpine, mahogany, hemlock,
ash, cedar, and even teak. The wood chosen should be readily avaiable,
easily worked and, most importantly, take glue well. My firs choice
would be spruce or Douglas fir (Oregon pine). Douglas fir is stronger
and more rot-resistant than spruce but heavier per cubic foot. If you
are weight-conscious and can't get spruce, check with a designer. You
can probably use a 20 per cent thinner mast wall and still end up with a
similar weight-to-strength ratio"
Regards
Francisco
"old fashioned" italian gaff-rigged catboat, with glassifbre mast,
called Difference. In the article, you can reed: "The mast, boom and
gaff are also glassfibre, centrifugally turned, making them light and
strong".
In issue #106, in an article call "making a mast" (by Larry Pardey):
"I have seen spars of spruce, douglas fir, pitchpine, mahogany, hemlock,
ash, cedar, and even teak. The wood chosen should be readily avaiable,
easily worked and, most importantly, take glue well. My firs choice
would be spruce or Douglas fir (Oregon pine). Douglas fir is stronger
and more rot-resistant than spruce but heavier per cubic foot. If you
are weight-conscious and can't get spruce, check with a designer. You
can probably use a 20 per cent thinner mast wall and still end up with a
similar weight-to-strength ratio"
Regards
Francisco
Uh-oh, Pippo, sounds like you should be building a Jessie Cooper or
maybe an AS-19! Time to order a new set of plans....
Seriously, the Micro has stood the test of time with a fine reputation
and many boats built. I love the daydreaming and "what if..." as much
as anybody, but maybe you ought to build it stock and see how you like
it before making any major mods?
Just my 2 cents (200 lire?), mind you,
Matthew
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
maybe an AS-19! Time to order a new set of plans....
Seriously, the Micro has stood the test of time with a fine reputation
and many boats built. I love the daydreaming and "what if..." as much
as anybody, but maybe you ought to build it stock and see how you like
it before making any major mods?
Just my 2 cents (200 lire?), mind you,
Matthew
"giuseppe 'pippo' bianco" <pippobianc-@...> wrote:
> Right on the target, Peter! I'm thinking very seriously about that
> possibility! I think that a gaff main would also be prettier, other
> than handier, and would allow to get rid of the sail track! Anybody
> fron PCB&F reading this thread?
Peter
"peter vanderwaart" <pvander-@...> wrote:
section below. I agree with you that a 1/2" square hollow means nothing
in terms of weight, and in fact my idea is to glue two full lenght
boards (9.0x4.5 cm^2 each) just to avoid warping.
Right on the target, Peter! I'm thinking very seriously about that
possibility! I think that a gaff main would also be prettier, other
than handier, and would allow to get rid of the sail track! Anybody
fron PCB&F reading this thread?
Best, Pippo
"peter vanderwaart" <pvander-@...> wrote:
> Is the Micro mast design solid, or Mr. Bolger's usual '4 stave roundIt's a tapered octagonal section above the heel, and a tapered square
> mast'?
section below. I agree with you that a 1/2" square hollow means nothing
in terms of weight, and in fact my idea is to glue two full lenght
boards (9.0x4.5 cm^2 each) just to avoid warping.
> Think how handy the mast of a Micro mast would be if it had a gaffrig.
Right on the target, Peter! I'm thinking very seriously about that
possibility! I think that a gaff main would also be prettier, other
than handier, and would allow to get rid of the sail track! Anybody
fron PCB&F reading this thread?
Best, Pippo
so far,
my expenses for the masts/ sprits/ for micro have been (37.50 main
mast+$28 sprits/mizzen)that comes to $65.50 US not counting replacing
the power tools that broke. I have used up about a quarter gallon of
WEST epoxy for the mizzen and sprits and have not glued the main mast
yet. The mizzen actually looks pretty good! the sprits better. This
has been using construction grade spruce with small tight knots.
I know that Boulter Ply has the material in stock but is it worth the
expense? Another interesting fact is that I found that their price for
marine grade ply was about $8 a sheet more than my local lumber yard
(Ashland Lumber) doing it on a special order. I know that Boulter's
service is great and you should expect to pay a little more for them to
have this stuff in stock, but at $8 a sheet it starts to add up
quickly.
Estimated expense for plywood is currently around $600 using
Marine grade 1/4 inch with the doubled bottom. At the extra $8 per
sheet that would add $120 to the cost. I plan to reinforce the deck
with small beams and glass cloth. other boats I have built have had
1/4 inch with absolutely no problems other than the flexing. The
cockpit seats might be 3/8 due to the fact that it might get a little
annoying after a while.
David Jost "Taxachusetts"
"clyde s. wisner" <clydewi-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3394
my expenses for the masts/ sprits/ for micro have been (37.50 main
mast+$28 sprits/mizzen)that comes to $65.50 US not counting replacing
the power tools that broke. I have used up about a quarter gallon of
WEST epoxy for the mizzen and sprits and have not glued the main mast
yet. The mizzen actually looks pretty good! the sprits better. This
has been using construction grade spruce with small tight knots.
I know that Boulter Ply has the material in stock but is it worth the
expense? Another interesting fact is that I found that their price for
marine grade ply was about $8 a sheet more than my local lumber yard
(Ashland Lumber) doing it on a special order. I know that Boulter's
service is great and you should expect to pay a little more for them to
have this stuff in stock, but at $8 a sheet it starts to add up
quickly.
Estimated expense for plywood is currently around $600 using
Marine grade 1/4 inch with the doubled bottom. At the extra $8 per
sheet that would add $120 to the cost. I plan to reinforce the deck
with small beams and glass cloth. other boats I have built have had
1/4 inch with absolutely no problems other than the flexing. The
cockpit seats might be 3/8 due to the fact that it might get a little
annoying after a while.
David Jost "Taxachusetts"
"clyde s. wisner" <clydewi-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3394
> I tried one out of poplar but it was still quite a bit heavier thangood
> lumber yard spruce, which replaced it. What about birds mouth, whereyou cut
> 8 strips, with birds mouth (90 degree vee) cut in one short side ofeach
> rectangle, and nest together, opposite short side of rect. in thebirds
> mouth beside it, to make almost circular mast. I found this in John'sMother
> of All Maritime Links, and I've seen articles in MAIB and WoodenBoat.to make
> www.vcnet.com/~fhagan/bm./htm but I haven't tried one yet. I did try
> a sample with a molding head on a radial arm saw and found that oneshould
> not try to run short pieces of wood thru a molding head. They cancome out
> like wooden bullets. Cheerful!, Clyde$8/board
>
> Peter Vanderwaart wrote:
>
> > Do I have this right? My surfing took me past www.boulterplywood.com
> > and they are running a special on sitka spruce, e.g. 16' 2x6 @
> > foot. My back-of-the envelope calculations (bear in mind that Idon't
> > have the mast design in front of me and don't know what I am doingin
> > any event) suggest that the material for a Micro main mast wouldrun in
> > the area of $250.wing
> >
> > Hmmm. Does anyone have the bill of material for a Gougeon Brothers
> > mast?the
> >
> > Peter
> >
> > p.s. I'm trying to decide which species of tree in my backyard is
> > most likely candidate for harvest as mast material. Oak is too heavyinventory.
> > and the trees are too large. The American Beech looks promising, but
> > the wood is very heavy and it seems to rot quickly once the tree is
> > dead. The birches have no strength. I'll have to review my
> >
I tried one out of poplar but it was still quite a bit heavier than good
lumber yard spruce, which replaced it. What about birds mouth, where you
cut 8 strips, with birds mouth (90 degree vee) cut in one short side of
each rectangle, and nest together, opposite short side of rect. in the
birds mouth beside it, to make almost circular mast. I found this in John's
Mother of All Maritime Links, and I've seen articles in MAIB and WoodenBoat.
www.vcnet.com/~fhagan/bm./htm but I haven't tried one yet. I did try to
make a sample with a molding head on a radial arm saw and found that one
should not try to run short pieces of wood thru a molding head. They can
come out like wooden bullets. Cheerful!, Clyde
Peter Vanderwaart wrote:
Do I have this right? My surfing took me past www.boulterplywood.com
and they are running a special on sitka spruce, e.g. 16' 2x6 @ $8/board
foot. My back-of-the envelope calculations (bear in mind that I don't
have the mast design in front of me and don't know what I am doing in
any event) suggest that the material for a Micro main mast would run in
the area of $250.
Hmmm. Does anyone have the bill of material for a Gougeon Brothers wing
mast?
Peter
p.s. I'm trying to decide which species of tree in my backyard is the
most likely candidate for harvest as mast material. Oak is too heavy
and the trees are too large. The American Beech looks promising, but
the wood is very heavy and it seems to rot quickly once the tree is
dead. The birches have no strength. I'll have to review my inventory.
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> > Still got less thanDo I have this right? My surfing took me past www.boulterplywood.com
> > $800 in a boat mast.
and they are running a special on sitka spruce, e.g. 16' 2x6 @ $8/board
foot. My back-of-the envelope calculations (bear in mind that I don't
have the mast design in front of me and don't know what I am doing in
any event) suggest that the material for a Micro main mast would run in
the area of $250.
Hmmm. Does anyone have the bill of material for a Gougeon Brothers wing
mast?
Peter
p.s. I'm trying to decide which species of tree in my backyard is the
most likely candidate for harvest as mast material. Oak is too heavy
and the trees are too large. The American Beech looks promising, but
the wood is very heavy and it seems to rot quickly once the tree is
dead. The birches have no strength. I'll have to review my inventory.
Pippo,
I got surprised by the big-sail-possibility when I got my plans. Before that, I liked the design, but I thought: "It would be perfect with a little more sail".
That's because the reports in this list were in general in this sense, and also because winds are here light in summer. As racer (beneteau "tupperware" first class 8), I know that you have to wait every w.e. (beer time) until the "garbí" (SW wind) ends up by blowing at 13:30 hours, with force 1.
But I don't have enough knowledges as to change the sail area myself, so I'm happy that Phil gives us this possibility.
For sure the wood weight is here a little more critical, but If I find any stability trouble in my finished boat (I don't think so), it's going to be relatively easy to cut the whole thing to the smaller specifications. The reverse process is more complicate...
Furthermore, I have no garage-size troubles. In fact, I have no garage ;-)
Regards
Francisco
Giuseppe 'Pippo' Bianco wrote:
Hi Francisco
francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...> wrote:
> original mast: 23'0"
>
> revised mast: 25'6"
Don't know what you think, but in my opinion the original mast is
plenty long enough. I think the longer one (almost 8 m) is a bit too
much, and could have some effect on the overall stability. Moreover
it
wouldn't fit into my garage... I'd rather play with a reacher like
suggested by Chuck Merrell. Also the summer winds in the Mediterranea
are not that light. My cruising area will be the Ionian and the
Tyrrenean seas and there's always a good breeze in sunny days.
Douglas Fir here costs about 1,500 Euros per m^3. Don't use dollar,
'cause it gets up day by day...
Best,
Pippo
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Thanks for your info, too. I don't mean to be too discouraging, if you
do it right you can have a lighter mast. If you use enough and you run
some of it all the way up, and use it cleverly, it could be good. I had
a bad experience with a model wing that I reinforced with carbon where
I didn't do my homework. More fragile than without the carbon. Didn't
want to see it happen to you with something on that scale.
"david jost" <djos-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3386
do it right you can have a lighter mast. If you use enough and you run
some of it all the way up, and use it cleverly, it could be good. I had
a bad experience with a model wing that I reinforced with carbon where
I didn't do my homework. More fragile than without the carbon. Didn't
want to see it happen to you with something on that scale.
"david jost" <djos-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3386
> Lincoln,a
>snip
> Many thanks for the information on Carbon Fiber, I was not aware of
> what it would do to the project (MICRO). I will omit the carbon fiber
> and just let the spar bend. This will be helpful in stronger winds
> anyways as it will allow some air to spill of the sail. Kind of like
> Laser.
> snip
Lincoln,
I have two good sources of Contruction Grade Spruce. Ashland Lumber,
Ashland MA. Any Carby's Supply on Hartford St in Framingham, MA. On a
similar note, they also sell #2 pine that is as good or better than #1
at Home Depot.
Many thanks for the information on Carbon Fiber, I was not aware of
what it would do to the project (MICRO). I will omit the carbon fiber
and just let the spar bend. This will be helpful in stronger winds
anyways as it will allow some air to spill of the sail. Kind of like a
Laser.
"lincoln ross" <lincoln-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3368
I have two good sources of Contruction Grade Spruce. Ashland Lumber,
Ashland MA. Any Carby's Supply on Hartford St in Framingham, MA. On a
similar note, they also sell #2 pine that is as good or better than #1
at Home Depot.
Many thanks for the information on Carbon Fiber, I was not aware of
what it would do to the project (MICRO). I will omit the carbon fiber
and just let the spar bend. This will be helpful in stronger winds
anyways as it will allow some air to spill of the sail. Kind of like a
Laser.
"lincoln ross" <lincoln-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3368
> "david jost" <djos-@...> wrote:town?
> original article:http://www.egroups.com/group/bolger/?start=3366
> > I have gone with construction grade spruce, as my lumber yard gets
> some
> > very good lumber. snip
> Is that a general trend for all their wood? What lumberyard? What
> > snipcarbon
> > Maybe it would be a good idea to wrap 2 spirals of kevlar or
> > fiber around the mast to reinforce it.carbon
> If you use a material like carbon, its elastic properties are very
> different than the wood. The carbon will take all the load until it
> breaks, then there will be a stress concentration at the edge of the
> carbon. Kind of like reinforcing a noodle with a thread, or a nylon
> line with a piece of wire. If you use the wood as a core and the
> as the main structural member, that's not so bad. I believe kevlar iscurrent.
> lousy in compression. Glass is a better elastic match with wood, or so
> I've heard. Of course that also means it's a lot more bendy. I suppose
> you could use carbon for the high stress parts of the mast, if you
> could figure out how to distribute the load at the end of the carbon.
> Also, you need to be very careful to protect the carbon at the
> partners. Kevlar wrap or glass might be good for that. I'm sure you
> could make a very good mast reinforced like this, but it would take
> some careful design. Also, I don't remember what you're building, but
> if you need to worry about lightning, you need some other conductive
> path. I understand that carbon is sort of a conductor but that it's
> resistance will generate a LOT of heat if it's carrying a high
>
> Model airplane wings with carbon spars are really strong, but they
> break all at once before you've even seen them bend. You can see the
> wooden ones bend before they let go. Carbon spars on model wings that
> fall across high tension lines wipe out power and are suddenly
> destroyed in a big flash (almost happened to my model once, it has a
> scuff mark under one wing).
>
Pippo,
Do you have high-speed internet access? If you look at my website
http://members.xoom.com/vandep
you can try out my 'Latar' applet. I have just put up what I call the
'first published version.' When finished, it will computer the lateral
areas of sails and underwater profiles, and calculate 'lead.' So far,
it just does the sails, and you could use it to compare the two Micro
rigs.
Unfortunately, the applet is very big: 2.6 meg. This is absurd for a
small program that just takes in a few numbers and does a couple of
calculations, but is the result of the version of Java in which it was
programmed. I hope to have a full explanation on the site by the end of
the weekend. If you have an ethernet connection or better, it will load
in about a minute. If you want to try it via a modem, better start
loading before breakfast. I suppose it could take 10-15 minutes, but I
don't really know. The applet was written as an exercise in learning
Java; usability is secondary.
A couple of comments on Micro masts. The larger rig does not have to
have a larger mast diameter because that parameter is mostly determined
by the stability of the hull. As long as the hull heels before the mast
breaks, you're ok. The balance with the larger rig is probably quite
similar. This is the flip side of the good balance of the jib-headed
cat yawl when reefed. The larger rig is an 'anti-reef' of the small
one. You probably would notice that it would be quicker to heel, if you
had the opportunity to compare.
Is the Micro mast design solid, or Mr. Bolger's usual '4 stave round
mast'? I assume that the reason he so often uses the 4 stave design is
that the smaller pieces of wood are much cheaper and easier to find
than larger ones. They are also easy to glue up on the factory-cut
perpendicular surfaces. The weight saved by the small hollow channel
cannot be much. In any boat of this size, I would try to work out a
mast of 16' 2x4's and/or 2x6's, keeping the scarfs the different staves
at different places along the span.
I have the MAIB article on Chebacco in front of me this morning. (How I
hunger for a Chebacco, sometimes.) The mainmast is about 20' long.
Think how handy the mast of a Micro mast would be if it had a gaff rig.
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
Do you have high-speed internet access? If you look at my website
http://members.xoom.com/vandep
you can try out my 'Latar' applet. I have just put up what I call the
'first published version.' When finished, it will computer the lateral
areas of sails and underwater profiles, and calculate 'lead.' So far,
it just does the sails, and you could use it to compare the two Micro
rigs.
Unfortunately, the applet is very big: 2.6 meg. This is absurd for a
small program that just takes in a few numbers and does a couple of
calculations, but is the result of the version of Java in which it was
programmed. I hope to have a full explanation on the site by the end of
the weekend. If you have an ethernet connection or better, it will load
in about a minute. If you want to try it via a modem, better start
loading before breakfast. I suppose it could take 10-15 minutes, but I
don't really know. The applet was written as an exercise in learning
Java; usability is secondary.
A couple of comments on Micro masts. The larger rig does not have to
have a larger mast diameter because that parameter is mostly determined
by the stability of the hull. As long as the hull heels before the mast
breaks, you're ok. The balance with the larger rig is probably quite
similar. This is the flip side of the good balance of the jib-headed
cat yawl when reefed. The larger rig is an 'anti-reef' of the small
one. You probably would notice that it would be quicker to heel, if you
had the opportunity to compare.
Is the Micro mast design solid, or Mr. Bolger's usual '4 stave round
mast'? I assume that the reason he so often uses the 4 stave design is
that the smaller pieces of wood are much cheaper and easier to find
than larger ones. They are also easy to glue up on the factory-cut
perpendicular surfaces. The weight saved by the small hollow channel
cannot be much. In any boat of this size, I would try to work out a
mast of 16' 2x4's and/or 2x6's, keeping the scarfs the different staves
at different places along the span.
I have the MAIB article on Chebacco in front of me this morning. (How I
hunger for a Chebacco, sometimes.) The mainmast is about 20' long.
Think how handy the mast of a Micro mast would be if it had a gaff rig.
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
> Seriously speaking now, I'd be curious to see what would happen to thePeter
> Micro sails' combined center of effort with the larger main. Since I
> don't see how to lower the foot, I expect the CE to be higher than in
> the original design, which would mean more heel and possibly different
> balance with the mizzen. What do you think?
Hello Pippo,
I stand corrected.Somehow read your posting differently.Can`t be
the snow as I would have gone crazy eons ago......must be the water!
With the Micro already very forgiving and no owner likely to
expect the Micro to handle like a Laser,I do not feel the slight shift
would produce serious consequences.The designer,however,would be better
placed to explain this and as it appears to be an option that was
tabled by the designer,would it not be reasonable to think that these
questions/doubts were already addressed by Mr.Bolger at the time of the
new sail plan commission?Just an idea.
Sincerely,
Peter Lenihan,head above the snow but now drinking bottled water,on the
frozen shores of the St.Lawrence,where a high of +3C is
expected...eventually.....
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3375
I stand corrected.Somehow read your posting differently.Can`t be
the snow as I would have gone crazy eons ago......must be the water!
With the Micro already very forgiving and no owner likely to
expect the Micro to handle like a Laser,I do not feel the slight shift
would produce serious consequences.The designer,however,would be better
placed to explain this and as it appears to be an option that was
tabled by the designer,would it not be reasonable to think that these
questions/doubts were already addressed by Mr.Bolger at the time of the
new sail plan commission?Just an idea.
Sincerely,
Peter Lenihan,head above the snow but now drinking bottled water,on the
frozen shores of the St.Lawrence,where a high of +3C is
expected...eventually.....
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3375
> Hi Peter,but
> while certainly the lost sleep (as the results) still has consequences
> over me, it also appears that the ice you're buried into has bad
> effects as well ;-), as I did not mention the difference in lenght,
> just the total lenght of the longer mast, which I approximated to 8with
> meters (it's 7.77 meters to be more precise)!
> Seriously speaking now, I'd be curious to see what would happen to the
> Micro sails' combined center of effort with the larger main. Since I
> don't see how to lower the foot, I expect the CE to be higher than in
> the original design, which would mean more heel and possibly different
> balance with the mizzen. What do you think?
>
> Best, Pippo
>
> in a beautiful sunny day, 20 knots northerly breeze, 10 degrees C,
> the radiotelescope out of my window noisily tracking quasarsrevised
>
> "peter lenihan" <ellengaes-@...> wrote:
> original article:http://www.egroups.com/group/bolger/?start=3374
> > Hi Pippo,
> > I do not believe the difference between the original and
> > mast amounts to 8m but is closer to 76cm!Not such a bigdifference,in
> > the end.But I suppose you are still somewhat reeling from the ACtoo
> > results?
> > Ciao,
> >
> >
> > Peter lenihan,staring out in shocked silence at falling and blowing
> > snow,once again,on the frozen shores of the St.Lawrence.......
> >
> >
> >
> >
> >
> >
> >
> > "giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
> > original article:http://www.egroups.com/group/bolger/?start=3373
> > > Hi Francisco
> > >
> > > francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...>
> > wrote:
> > >
> > > > original mast: 23'0"
> > > >
> > > > revised mast: 25'6"
> > >
> > > Don't know what you think, but in my opinion the original mast is
> > > plenty long enough. I think the longer one (almost 8 m) is a bit
> > > much, and could have some effect on the overall stability.Moreover
> itdollar,
> > > wouldn't fit into my garage... I'd rather play with a reacher like
> > > suggested by Chuck Merrell. Also the summer winds in the
> Mediterranea
> > > are not that light. My cruising area will be the Ionian and the
> > > Tyrrenean seas and there's always a good breeze in sunny days.
> > > Douglas Fir here costs about 1,500 Euros per m^3. Don't use
> > > 'cause it gets up day by day...
> > >
> > > Best,
> > >
> > > Pippo
> > >
> > >
> >
>
"ed haile" <ewhail-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3370
more material up high than you need. If I was doing it I'd try to have
extra material or a plug inside the partners and something extra on the
outside at that point. All with tapering transitions.
Heh, heh. I am looking for a
to know the strength of the particular materials you're using. And I'd
have to brush up on my engineering skills. I've been designing metal
boxes for too long.
I'm sure it could be done with careful design.
Or buying two & thrusting
original article:http://www.egroups.com/group/bolger/?start=3370
> To Lincoln Rossam
>
> What about a ready-made mast in the form of a fiberglass flagpole? I
> told they will bend but never break.I don't know of any reason why it wouldn't. Flagpole will probably have
more material up high than you need. If I was doing it I'd try to have
extra material or a plug inside the partners and something extra on the
outside at that point. All with tapering transitions.
Heh, heh. I am looking for a
> Martha Jane mast, a 20 ft spar. Glass flagpoles come 22ft with a 5"I'd have to do some serious calculations to tell you that, and I'd have
> base tapering to 3", 0.15" wall, weighs about 30 lbs, $395. Is this
> stuff any good or is it too bendy, too weak, too what?
to know the strength of the particular materials you're using. And I'd
have to brush up on my engineering skills. I've been designing metal
boxes for too long.
>If so, whatI'd expect some of the same issues as with reinforcing the wood, but
> about stiffening it by adding carbon fiber?
I'm sure it could be done with careful design.
Or buying two & thrusting
> one up inside the other (smeared with wet epoxy)? Still got less thanI dunno, maybe. Seems like for $800 it would be worth making a wood one.
> $800 in a boat mast.
>Maybe. Would need a little larger dia. than solid wood.
> After that, what about tubular plywood?
Hi Peter,
while certainly the lost sleep (as the results) still has consequences
over me, it also appears that the ice you're buried into has bad
effects as well ;-), as I did not mention the difference in lenght, but
just the total lenght of the longer mast, which I approximated to 8
meters (it's 7.77 meters to be more precise)!
Seriously speaking now, I'd be curious to see what would happen to the
Micro sails' combined center of effort with the larger main. Since I
don't see how to lower the foot, I expect the CE to be higher than in
the original design, which would mean more heel and possibly different
balance with the mizzen. What do you think?
Best, Pippo
in a beautiful sunny day, 20 knots northerly breeze, 10 degrees C, with
the radiotelescope out of my window noisily tracking quasars
"peter lenihan" <ellengaes-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3374
while certainly the lost sleep (as the results) still has consequences
over me, it also appears that the ice you're buried into has bad
effects as well ;-), as I did not mention the difference in lenght, but
just the total lenght of the longer mast, which I approximated to 8
meters (it's 7.77 meters to be more precise)!
Seriously speaking now, I'd be curious to see what would happen to the
Micro sails' combined center of effort with the larger main. Since I
don't see how to lower the foot, I expect the CE to be higher than in
the original design, which would mean more heel and possibly different
balance with the mizzen. What do you think?
Best, Pippo
in a beautiful sunny day, 20 knots northerly breeze, 10 degrees C, with
the radiotelescope out of my window noisily tracking quasars
"peter lenihan" <ellengaes-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3374
> Hi Pippo,it
> I do not believe the difference between the original and revised
> mast amounts to 8m but is closer to 76cm!Not such a big difference,in
> the end.But I suppose you are still somewhat reeling from the AC
> results?
> Ciao,
>
>
> Peter lenihan,staring out in shocked silence at falling and blowing
> snow,once again,on the frozen shores of the St.Lawrence.......
>
>
>
>
>
>
>
> "giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
> original article:http://www.egroups.com/group/bolger/?start=3373
> > Hi Francisco
> >
> > francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...>
> wrote:
> >
> > > original mast: 23'0"
> > >
> > > revised mast: 25'6"
> >
> > Don't know what you think, but in my opinion the original mast is
> > plenty long enough. I think the longer one (almost 8 m) is a bit too
> > much, and could have some effect on the overall stability. Moreover
> > wouldn't fit into my garage... I'd rather play with a reacher likeMediterranea
> > suggested by Chuck Merrell. Also the summer winds in the
> > are not that light. My cruising area will be the Ionian and the
> > Tyrrenean seas and there's always a good breeze in sunny days.
> > Douglas Fir here costs about 1,500 Euros per m^3. Don't use dollar,
> > 'cause it gets up day by day...
> >
> > Best,
> >
> > Pippo
> >
> >
>
Hi Pippo,
I do not believe the difference between the original and revised
mast amounts to 8m but is closer to 76cm!Not such a big difference,in
the end.But I suppose you are still somewhat reeling from the AC
results?
Ciao,
Peter lenihan,staring out in shocked silence at falling and blowing
snow,once again,on the frozen shores of the St.Lawrence.......
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3373
I do not believe the difference between the original and revised
mast amounts to 8m but is closer to 76cm!Not such a big difference,in
the end.But I suppose you are still somewhat reeling from the AC
results?
Ciao,
Peter lenihan,staring out in shocked silence at falling and blowing
snow,once again,on the frozen shores of the St.Lawrence.......
"giuseppe 'pippo' bianco" <giuseppe.bianc-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3373
> Hi Franciscowrote:
>
> francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...>
>
> > original mast: 23'0"
> >
> > revised mast: 25'6"
>
> Don't know what you think, but in my opinion the original mast is
> plenty long enough. I think the longer one (almost 8 m) is a bit too
> much, and could have some effect on the overall stability. Moreover it
> wouldn't fit into my garage... I'd rather play with a reacher like
> suggested by Chuck Merrell. Also the summer winds in the Mediterranea
> are not that light. My cruising area will be the Ionian and the
> Tyrrenean seas and there's always a good breeze in sunny days.
> Douglas Fir here costs about 1,500 Euros per m^3. Don't use dollar,
> 'cause it gets up day by day...
>
> Best,
>
> Pippo
>
>
Hi Francisco
francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...> wrote:
plenty long enough. I think the longer one (almost 8 m) is a bit too
much, and could have some effect on the overall stability. Moreover it
wouldn't fit into my garage... I'd rather play with a reacher like
suggested by Chuck Merrell. Also the summer winds in the Mediterranea
are not that light. My cruising area will be the Ionian and the
Tyrrenean seas and there's always a good breeze in sunny days.
Douglas Fir here costs about 1,500 Euros per m^3. Don't use dollar,
'cause it gets up day by day...
Best,
Pippo
francisco =?iso-8859-1?q?ram=edrez?= <astrolabi-@...> wrote:
> original mast: 23'0"Don't know what you think, but in my opinion the original mast is
>
> revised mast: 25'6"
plenty long enough. I think the longer one (almost 8 m) is a bit too
much, and could have some effect on the overall stability. Moreover it
wouldn't fit into my garage... I'd rather play with a reacher like
suggested by Chuck Merrell. Also the summer winds in the Mediterranea
are not that light. My cruising area will be the Ionian and the
Tyrrenean seas and there's always a good breeze in sunny days.
Douglas Fir here costs about 1,500 Euros per m^3. Don't use dollar,
'cause it gets up day by day...
Best,
Pippo
To Lincoln Ross
What about a ready-made mast in the form of a fiberglass flagpole? I am
told they will bend but never break. Heh, heh. I am looking for a
Martha Jane mast, a 20 ft spar. Glass flagpoles come 22ft with a 5"
base tapering to 3", 0.15" wall, weighs about 30 lbs, $395. Is this
stuff any good or is it too bendy, too weak, too what? If so, what
about stiffening it by adding carbon fiber? Or buying two & thrusting
one up inside the other (smeared with wet epoxy)? Still got less than
$800 in a boat mast.
After that, what about tubular plywood?
"lincoln ross" <lincoln-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3368
What about a ready-made mast in the form of a fiberglass flagpole? I am
told they will bend but never break. Heh, heh. I am looking for a
Martha Jane mast, a 20 ft spar. Glass flagpoles come 22ft with a 5"
base tapering to 3", 0.15" wall, weighs about 30 lbs, $395. Is this
stuff any good or is it too bendy, too weak, too what? If so, what
about stiffening it by adding carbon fiber? Or buying two & thrusting
one up inside the other (smeared with wet epoxy)? Still got less than
$800 in a boat mast.
After that, what about tubular plywood?
"lincoln ross" <lincoln-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3368
> "david jost" <djos-@...> wrote:town?
> original article:http://www.egroups.com/group/bolger/?start=3366
> > I have gone with construction grade spruce, as my lumber yard gets
> some
> > very good lumber. snip
> Is that a general trend for all their wood? What lumberyard? What
> > snipcarbon
> > Maybe it would be a good idea to wrap 2 spirals of kevlar or
> > fiber around the mast to reinforce it.carbon
> If you use a material like carbon, its elastic properties are very
> different than the wood. The carbon will take all the load until it
> breaks, then there will be a stress concentration at the edge of the
> carbon. Kind of like reinforcing a noodle with a thread, or a nylon
> line with a piece of wire. If you use the wood as a core and the
> as the main structural member, that's not so bad. I believe kevlar iscurrent.
> lousy in compression. Glass is a better elastic match with wood, or so
> I've heard. Of course that also means it's a lot more bendy. I suppose
> you could use carbon for the high stress parts of the mast, if you
> could figure out how to distribute the load at the end of the carbon.
> Also, you need to be very careful to protect the carbon at the
> partners. Kevlar wrap or glass might be good for that. I'm sure you
> could make a very good mast reinforced like this, but it would take
> some careful design. Also, I don't remember what you're building, but
> if you need to worry about lightning, you need some other conductive
> path. I understand that carbon is sort of a conductor but that it's
> resistance will generate a LOT of heat if it's carrying a high
>
> Model airplane wings with carbon spars are really strong, but they
> break all at once before you've even seen them bend. You can see the
> wooden ones bend before they let go. Carbon spars on model wings that
> fall across high tension lines wipe out power and are suddenly
> destroyed in a big flash (almost happened to my model once, it has a
> scuff mark under one wing).
>
> >Good straight grained Douglas fir is a very strong wood. It is a
> >I plan to use douglas fir, which oddly enough is probably THE most
> >expensive wood species available in Italy. The lumberyard I use told me
> >that douglas fir boards are available up to 13 meters in lenght.
>
little on the heavy side compared to spruce.
If it were me I would go with what the mast maker recommends. He
has a lot more experience with the wood available there than we
do.
Good luck
Gordon W5RED
G. C. Cougergcouger@...Stillwater, OK
www.couger.com/gcouger
"You miss 100 percent of the shots you never take." - Wayne Gretzky
"david jost" <djos-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3366
different than the wood. The carbon will take all the load until it
breaks, then there will be a stress concentration at the edge of the
carbon. Kind of like reinforcing a noodle with a thread, or a nylon
line with a piece of wire. If you use the wood as a core and the carbon
as the main structural member, that's not so bad. I believe kevlar is
lousy in compression. Glass is a better elastic match with wood, or so
I've heard. Of course that also means it's a lot more bendy. I suppose
you could use carbon for the high stress parts of the mast, if you
could figure out how to distribute the load at the end of the carbon.
Also, you need to be very careful to protect the carbon at the
partners. Kevlar wrap or glass might be good for that. I'm sure you
could make a very good mast reinforced like this, but it would take
some careful design. Also, I don't remember what you're building, but
if you need to worry about lightning, you need some other conductive
path. I understand that carbon is sort of a conductor but that it's
resistance will generate a LOT of heat if it's carrying a high current.
Model airplane wings with carbon spars are really strong, but they
break all at once before you've even seen them bend. You can see the
wooden ones bend before they let go. Carbon spars on model wings that
fall across high tension lines wipe out power and are suddenly
destroyed in a big flash (almost happened to my model once, it has a
scuff mark under one wing).
original article:http://www.egroups.com/group/bolger/?start=3366
> I have gone with construction grade spruce, as my lumber yard getssome
> very good lumber. snipIs that a general trend for all their wood? What lumberyard? What town?
> snipIf you use a material like carbon, its elastic properties are very
> Maybe it would be a good idea to wrap 2 spirals of kevlar or carbon
> fiber around the mast to reinforce it.
different than the wood. The carbon will take all the load until it
breaks, then there will be a stress concentration at the edge of the
carbon. Kind of like reinforcing a noodle with a thread, or a nylon
line with a piece of wire. If you use the wood as a core and the carbon
as the main structural member, that's not so bad. I believe kevlar is
lousy in compression. Glass is a better elastic match with wood, or so
I've heard. Of course that also means it's a lot more bendy. I suppose
you could use carbon for the high stress parts of the mast, if you
could figure out how to distribute the load at the end of the carbon.
Also, you need to be very careful to protect the carbon at the
partners. Kevlar wrap or glass might be good for that. I'm sure you
could make a very good mast reinforced like this, but it would take
some careful design. Also, I don't remember what you're building, but
if you need to worry about lightning, you need some other conductive
path. I understand that carbon is sort of a conductor but that it's
resistance will generate a LOT of heat if it's carrying a high current.
Model airplane wings with carbon spars are really strong, but they
break all at once before you've even seen them bend. You can see the
wooden ones bend before they let go. Carbon spars on model wings that
fall across high tension lines wipe out power and are suddenly
destroyed in a big flash (almost happened to my model once, it has a
scuff mark under one wing).
At 12:47 AM 3/2/00 -0800, you wrote:
today. I''ve been traveling all week in Oregon (where they cut a lot of
Douglas fir!). Just this afternoon, I passed a truck hauling doug fir
2x10's that were 38 feet long!
John Bell - sitting in the Holiday Inn at the Portland, Oregon Airport
looking forward to getting on that airplane and going home tomorrow... But
not before a few beers in the bar!
John Bell -jmbell@...
---------------------------------
http://jmbell.home.mindspring.com
>Hi FranciscoI would not have beleived it was availible in such long lengths until
>
>I plan to use douglas fir, which oddly enough is probably THE most
>expensive wood species available in Italy. The lumberyard I use told me
>that douglas fir boards are available up to 13 meters in lenght.
today. I''ve been traveling all week in Oregon (where they cut a lot of
Douglas fir!). Just this afternoon, I passed a truck hauling doug fir
2x10's that were 38 feet long!
John Bell - sitting in the Holiday Inn at the Portland, Oregon Airport
looking forward to getting on that airplane and going home tomorrow... But
not before a few beers in the bar!
John Bell -jmbell@...
---------------------------------
http://jmbell.home.mindspring.com
I have gone with construction grade spruce, as my lumber yard gets some
very good lumber. It is straight with small tight knots. Today I
ripped two 16' 2X 8's which will then be scarfed to make the large
staves of the main mast. I plan to stagger the scarfs throughout the
mast (including the 1/2 inch staves) which is why I went to the 16
footers rather than the 14 footers. The cost for both planks was $37
US. Not bad.
As I understand it, the epoxy scarfs should be stronger than the
actual wood. If the mast breaks, all I would have lost is about $50,
if I include the cost of the epoxy and sandpaper. However, if the
sailtrack bends. . . ouch!
Maybe it would be a good idea to wrap 2 spirals of kevlar or carbon
fiber around the mast to reinforce it. It is not too expensive and is
easy to apply. I would have to coat the mast in some serious UV
protection, as I am aware that this combination breaks down quickly.
(or I could move to Seattle where it is cloudy all the time)
"p. vanderwaart" <pvander-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3365
very good lumber. It is straight with small tight knots. Today I
ripped two 16' 2X 8's which will then be scarfed to make the large
staves of the main mast. I plan to stagger the scarfs throughout the
mast (including the 1/2 inch staves) which is why I went to the 16
footers rather than the 14 footers. The cost for both planks was $37
US. Not bad.
As I understand it, the epoxy scarfs should be stronger than the
actual wood. If the mast breaks, all I would have lost is about $50,
if I include the cost of the epoxy and sandpaper. However, if the
sailtrack bends. . . ouch!
Maybe it would be a good idea to wrap 2 spirals of kevlar or carbon
fiber around the mast to reinforce it. It is not too expensive and is
easy to apply. I would have to coat the mast in some serious UV
protection, as I am aware that this combination breaks down quickly.
(or I could move to Seattle where it is cloudy all the time)
"p. vanderwaart" <pvander-@...> wrote:
original article:http://www.egroups.com/group/bolger/?start=3365
> To quote an old mentor of mine, "I only know enough to be dangerous,and
> I''ve already told you more than I know."mast. The
>
> Around here some 2-4's have a spiral grain and are referred to as
> 'hemlock.' It splinters and twists and is NOT what you want in a
> names put to woods are very regional even in this modern day. So takea
> good look at what you are getting.and in
>
> Peter
>
>
>
> >Hemlock here on Canada's wet coast is nice, straight grained stuff,
> >your position, I's agree with the sailmaker. Scots pine can be gummystuff
> >to work with and finish. I'm using Doug. Fir for my Micro mastsbecause it
> >seems easier to get, and cheaper here.
>
To quote an old mentor of mine, "I only know enough to be dangerous, and
I''ve already told you more than I know."
Around here some 2-4's have a spiral grain and are referred to as
'hemlock.' It splinters and twists and is NOT what you want in a mast. The
names put to woods are very regional even in this modern day. So take a
good look at what you are getting.
Peter
I''ve already told you more than I know."
Around here some 2-4's have a spiral grain and are referred to as
'hemlock.' It splinters and twists and is NOT what you want in a mast. The
names put to woods are very regional even in this modern day. So take a
good look at what you are getting.
Peter
>Hemlock here on Canada's wet coast is nice, straight grained stuff, and in
>your position, I's agree with the sailmaker. Scots pine can be gummy stuff
>to work with and finish. I'm using Doug. Fir for my Micro masts because it
>seems easier to get, and cheaper here.
Hi Francisco
Hemlock here on Canada's wet coast is nice, straight grained stuff, and in
your position, I's agree with the sailmaker. Scots pine can be gummy stuff
to work with and finish. I'm using Doug. Fir for my Micro masts because it
seems easier to get, and cheaper here.
The only thing I would add to your list of dimensions for the longer mast is
that I think I recall PB&F suggested extending the untapered section of the
mast, rather than 'stretching' the taper out.
As a general question, why do people seem to lean towards the 'single stick'
length for mast timber? I had fully intended using staggered scarfs in the
timbers for my main (to be built hollow, 'birdsmouth' fashion). Have people
had horrible 'snapped mast' experiences?
Derek
Hemlock here on Canada's wet coast is nice, straight grained stuff, and in
your position, I's agree with the sailmaker. Scots pine can be gummy stuff
to work with and finish. I'm using Doug. Fir for my Micro masts because it
seems easier to get, and cheaper here.
The only thing I would add to your list of dimensions for the longer mast is
that I think I recall PB&F suggested extending the untapered section of the
mast, rather than 'stretching' the taper out.
As a general question, why do people seem to lean towards the 'single stick'
length for mast timber? I had fully intended using staggered scarfs in the
timbers for my main (to be built hollow, 'birdsmouth' fashion). Have people
had horrible 'snapped mast' experiences?
Derek
Giuseppe 'Pippo' Bianco wrote:
In my plans I have the standard main mast/sail plus the revised version
dated 8/96. Phil recommended me to consider the last one, due to the light
mediterranean summer winds.
original mast: 23'0"
" surface: 119sqft
" luff: 19'0"
" leech: 20'11"
" foot: 12'8"
revised mast: 25'6"
" surface: 134sqft (circa un metro e mezzo in piú)
" luff: 21'6"
" leech: 23'0"
" foot: 12'8"
The mast thickness seams to be the same... just longer. The boom has exactly
the same situation. So, if you decide go this way, you don't need extra
plans, this information mast be enough.
Today I visited another mast-maker, and he told me that he used to work with
stika spruce. He gave me some telefon-numbers, but I coudn't find the
"original stuff". It seems they don't import it anymore.
Douglas fir costs here U$S 1780/m3 (sorry, I don't know hou to make the
conversion in ft3).
Regards
Francisco
>Pippo,
> I've one question though: what do you mean by "Micro enlarged mast"? Is
> there a new sail plan for the boat other than the Navigator rig?
>
> Thanks, Pippo
In my plans I have the standard main mast/sail plus the revised version
dated 8/96. Phil recommended me to consider the last one, due to the light
mediterranean summer winds.
original mast: 23'0"
" surface: 119sqft
" luff: 19'0"
" leech: 20'11"
" foot: 12'8"
revised mast: 25'6"
" surface: 134sqft (circa un metro e mezzo in piú)
" luff: 21'6"
" leech: 23'0"
" foot: 12'8"
The mast thickness seams to be the same... just longer. The boom has exactly
the same situation. So, if you decide go this way, you don't need extra
plans, this information mast be enough.
Today I visited another mast-maker, and he told me that he used to work with
stika spruce. He gave me some telefon-numbers, but I coudn't find the
"original stuff". It seems they don't import it anymore.
Douglas fir costs here U$S 1780/m3 (sorry, I don't know hou to make the
conversion in ft3).
Regards
Francisco
Hi Francisco
expensive wood species available in Italy. The lumberyard I use told me
that douglas fir boards are available up to 13 meters in lenght.
I've one question though: what do you mean by "Micro enlarged mast"? Is
there a new sail plan for the boat other than the Navigator rig?
Thanks, Pippo
> I found cheap "abeto de flandes" (pinus silvestris), expensive douglasneed
> fir (five times the pinus's price), and western hemlock (3,5 times the
> pinus's price). Today I talked to a sailmaker and to a mastmaker, and
> they recomended me the last one. Its not easy to find the length I
> (25' 6" for the enlarged micro mast), but not impossible ifcomissioned.
> Any experiences with this stuff ?I plan to use douglas fir, which oddly enough is probably THE most
expensive wood species available in Italy. The lumberyard I use told me
that douglas fir boards are available up to 13 meters in lenght.
I've one question though: what do you mean by "Micro enlarged mast"? Is
there a new sail plan for the boat other than the Navigator rig?
Thanks, Pippo
I have some troubles to find the correct wood for mast making. The main
problem is that spruce is not imported here, so I decided to look for
other possibilities.
I found cheap "abeto de flandes" (pinus silvestris), expensive douglas
fir (five times the pinus's price), and western hemlock (3,5 times the
pinus's price). Today I talked to a sailmaker and to a mastmaker, and
they recomended me the last one. Its not easy to find the length I need
(25' 6" for the enlarged micro mast), but not impossible if comissioned.
Any experiences with this stuff ?
Back to the sailmaker, his name is Toni Tió, a very good one, and his
factory is ten minutes driving from my home. Boats with his sails won a
lot of olympic medals, and is known as expensive... but he gave me a
reasonable budget: U$S 894 for the big main (134sqft) with two reef and
the mizzen. I have to take him the completed boat to measure the mast
flexion... so I think he's going to wait for a while!
Regards
Francisco
problem is that spruce is not imported here, so I decided to look for
other possibilities.
I found cheap "abeto de flandes" (pinus silvestris), expensive douglas
fir (five times the pinus's price), and western hemlock (3,5 times the
pinus's price). Today I talked to a sailmaker and to a mastmaker, and
they recomended me the last one. Its not easy to find the length I need
(25' 6" for the enlarged micro mast), but not impossible if comissioned.
Any experiences with this stuff ?
Back to the sailmaker, his name is Toni Tió, a very good one, and his
factory is ten minutes driving from my home. Boats with his sails won a
lot of olympic medals, and is known as expensive... but he gave me a
reasonable budget: U$S 894 for the big main (134sqft) with two reef and
the mizzen. I have to take him the completed boat to measure the mast
flexion... so I think he's going to wait for a while!
Regards
Francisco