Re: Best place to order clear vertical grain lumber...
I would guess that a safety factor of one would mean that the mast was
just strong enough to knock down the boat. You'd want a little more for
waves hitting the sails and such after it's knocked down, and more
because nothing is perfect and you probably have some extra loading
around the partners, etc. I would say that a safety factor of one would
be LESS than absolutely necessary, given the above, even with the best
wood.
just strong enough to knock down the boat. You'd want a little more for
waves hitting the sails and such after it's knocked down, and more
because nothing is perfect and you probably have some extra loading
around the partners, etc. I would say that a safety factor of one would
be LESS than absolutely necessary, given the above, even with the best
wood.
>Peter Lenihan wrote:snip
>
>
>
>Hi Bruce,
> I recall reading somewhere a long time ago(Elrowe's newsletter
>or Common Sense Designs Newletter perhaps?) that the mast for the
>Micro was designed with a safety factor of 4. I never really
>understood exactly what this meant but I took it to mean that the
>mast was designed 4 times stonger then absolutely necessary for that
>size rig and boat.I suspected that the reason for this,other then
>pure safety, was Bolger's anticipation that amateur builders would
>not necessarily have access to or wish to pay for premium grade mast
>stock.
>
I think it would be much cheaper from Aircraft Spruce (yes they sell
carbon also), Wickes, or some other place that sells large amounts of
composites. RC airplanes only use tiny amounts compared to a mast. Other
outfits I remember are Composite Structures Technology (web site might
be cstsales.com) or Aerospace Composite Products, tho I don't know how
cheap since they sell to model airplane guys a lot. I'm sure you can
find these and more by surfing. But any carbon would have to be
carefully protected from dents by the partners or it would buckle. I
know of at least one carbon fiber reinforced wood mast that failed, I
think from this problem. It was on a Bolger boat, too, tho carbon was
not part of the original design. Anyone going this route should probably
do quite a bit of homework first.
carbon also), Wickes, or some other place that sells large amounts of
composites. RC airplanes only use tiny amounts compared to a mast. Other
outfits I remember are Composite Structures Technology (web site might
be cstsales.com) or Aerospace Composite Products, tho I don't know how
cheap since they sell to model airplane guys a lot. I'm sure you can
find these and more by surfing. But any carbon would have to be
carefully protected from dents by the partners or it would buckle. I
know of at least one carbon fiber reinforced wood mast that failed, I
think from this problem. It was on a Bolger boat, too, tho carbon was
not part of the original design. Anyone going this route should probably
do quite a bit of homework first.
>jim dorey wrote:
>rc airplane shops sell relatively cheap carbon fibre tape in bulk, maybe
>laminating that on the front in this situation would make the wood only
>need to take compression, you could use almost anything then.
>
What diameter do the Old Shoe plans
specify for the main and mizzen masts?
specify for the main and mizzen masts?
But where did the designer start?
I'd guess the impact loading associated with a goose-wing jibe might
represent a worst case loading. Still guessing, but once the rig's in the
water, it would seem like the loads might be less, but then of course they
would be from novel directions. ????
Roger
derbyrm at starband.net
http://derbyrm.mystarband.net
I'd guess the impact loading associated with a goose-wing jibe might
represent a worst case loading. Still guessing, but once the rig's in the
water, it would seem like the loads might be less, but then of course they
would be from novel directions. ????
Roger
derbyrm at starband.net
http://derbyrm.mystarband.net
----- Original Message -----
From: "Lincoln Ross" <lincolnr@...>
To: <bolger@yahoogroups.com>
Sent: Friday, March 12, 2004 2:51 PM
Subject: [bolger] Re: Best place to order clear vertical grain lumber...
> I would guess that a safety factor of one would mean that the mast was
> just strong enough to knock down the boat. You'd want a little more for
> waves hitting the sails and such after it's knocked down, and more
> because nothing is perfect and you probably have some extra loading
> around the partners, etc. I would say that a safety factor of one would
> be LESS than absolutely necessary, given the above, even with the best
> wood.
>
> >Peter Lenihan wrote:
> >
> >
> >
> >Hi Bruce,
> > I recall reading somewhere a long time ago(Elrowe's newsletter
> >or Common Sense Designs Newletter perhaps?) that the mast for the
> >Micro was designed with a safety factor of 4. I never really
> >understood exactly what this meant but I took it to mean that the
> >mast was designed 4 times stonger then absolutely necessary for that
> >size rig and boat.I suspected that the reason for this,other then
> >pure safety, was Bolger's anticipation that amateur builders would
> >not necessarily have access to or wish to pay for premium grade mast
> >stock.
> >
> snip
>
>
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
(978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
> Yahoo! Groups Links
>
>
>
>
>
--- Inbolger@yahoogroups.com, Bruce Hallman <bruce@h...> wrote:
I recall reading somewhere a long time ago(Elrowe's newsletter
or Common Sense Designs Newletter perhaps?) that the mast for the
Micro was designed with a safety factor of 4. I never really
understood exactly what this meant but I took it to mean that the
mast was designed 4 times stonger then absolutely necessary for that
size rig and boat.I suspected that the reason for this,other then
pure safety, was Bolger's anticipation that amateur builders would
not necessarily have access to or wish to pay for premium grade mast
stock. Perhaps the same approach was used when he designed the Old
Shoe mast?
Regarding shopping for mast stock at generic lumber
yards/stores,you're absolutley right on! I was able to get some
really nice Eastern white spruce by picking out the clearest deals(2
X 12s and 2 X 14s) from the usual pile of pretzels. By going with
deals,instead of 2 X 3 and 2 X 4 stock, it is even easier to get very
good lengths of clear straight grained cuts. If I remember right, I
was able to get out all the spars for LESTAT from 4 or 5 deals for
about $150.00CAN. Had I chosen Sitka spruce,the bill would have run a
couple of thousand and no one would have noticed the
difference.........
When I built my Elver,I managed to get hold of some Northern
black spruce from an old lumber yard that had a big stack of deals
languishing out in the back shed.The annual rings were so tight that
a boatbuilder friend thought I had bought Sitka spruce! Sadly,that
lumber yard had shut down by the time I built my Micro........
But yes,it really pays to root around the big box stores
lumber piles :-)
Sincerely,
Peter Lenihan
> If safety factor is the issue, increasingHi Bruce,
> the diameter of the mast is another
> effective way to make them stronger
> while still using cheap wood.
I recall reading somewhere a long time ago(Elrowe's newsletter
or Common Sense Designs Newletter perhaps?) that the mast for the
Micro was designed with a safety factor of 4. I never really
understood exactly what this meant but I took it to mean that the
mast was designed 4 times stonger then absolutely necessary for that
size rig and boat.I suspected that the reason for this,other then
pure safety, was Bolger's anticipation that amateur builders would
not necessarily have access to or wish to pay for premium grade mast
stock. Perhaps the same approach was used when he designed the Old
Shoe mast?
Regarding shopping for mast stock at generic lumber
yards/stores,you're absolutley right on! I was able to get some
really nice Eastern white spruce by picking out the clearest deals(2
X 12s and 2 X 14s) from the usual pile of pretzels. By going with
deals,instead of 2 X 3 and 2 X 4 stock, it is even easier to get very
good lengths of clear straight grained cuts. If I remember right, I
was able to get out all the spars for LESTAT from 4 or 5 deals for
about $150.00CAN. Had I chosen Sitka spruce,the bill would have run a
couple of thousand and no one would have noticed the
difference.........
When I built my Elver,I managed to get hold of some Northern
black spruce from an old lumber yard that had a big stack of deals
languishing out in the back shed.The annual rings were so tight that
a boatbuilder friend thought I had bought Sitka spruce! Sadly,that
lumber yard had shut down by the time I built my Micro........
But yes,it really pays to root around the big box stores
lumber piles :-)
Sincerely,
Peter Lenihan
If I couldn't get clear wood, I don't think I'd be tempted to order it
from Aircraft Spruce as my intuition is that a composite mast could be
built for less. Of course if you don't like messing with engineering and
goo, than maybe that's not a valid approach. My first approach would be
to pick through what I saw at lumber places. After a few hours, I should
think something suitable would show up. It only takes me about an hour
to find a 2X4 good enough for an oar!
Lincoln Ross
from Aircraft Spruce as my intuition is that a composite mast could be
built for less. Of course if you don't like messing with engineering and
goo, than maybe that's not a valid approach. My first approach would be
to pick through what I saw at lumber places. After a few hours, I should
think something suitable would show up. It only takes me about an hour
to find a 2X4 good enough for an oar!
Lincoln Ross
rc airplane shops sell relatively cheap carbon fibre tape in bulk, maybe
laminating that on the front in this situation would make the wood only
need to take compression, you could use almost anything then.
proaconstrictor wrote:
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
laminating that on the front in this situation would make the wood only
need to take compression, you could use almost anything then.
proaconstrictor wrote:
>--
> Most Bolger unstayed rigs put the aft of the spar under tension, that
> is the only place you need the really good stuff, put your best piece
> there.
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
they guys on the origamiboats list have discussed aluminum and steel
pipe as masts, thin wall steel being cheap and not too much heavier than
aluminum would possibly be a good choice.
Bruce Hallman wrote:
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
pipe as masts, thin wall steel being cheap and not too much heavier than
aluminum would possibly be a good choice.
Bruce Hallman wrote:
> Even a home grown sapling tree could--
> work for a mast. Also, though not cheap,
> an aluminum tube 'schedule 40 pipe' could
> serve as a mast.
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
ask for lumberlady on the woodworkgalore list.
smithriverranger wrote:
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
smithriverranger wrote:
> I can't get decent wood around here and i'm trying to find wood for--
> my spars.I've had bad luck in the past with laminating poor quality
> wood. Mainly concerned with finding wood for my oldshoe's main mast.
> Don't want to scarf wood for this part of the boat so i need some
> long lengths. Where can i order some cvg sitka spruce or something
> like it. I know this is going to cost me but i'm trying for once to
> not use scraps and make a top quality boat.
> oh yeah is kiln dried wood bad for spars?
> Thanks for any help,
> Jason
http://www.skaar.101main.net
http://www.PetitionOnline.com/spcdvd/
http://www.petitiononline.com/impjapan/petition-sign.html?
moderator ofwildsteam@yahoogroups.com
DOM and proud!!!
I think a spar should have good wood, but not necesarily great wood.
Great wood is straight perfect fine grain in a superior species like
SS. Good wood is nice straight stuff in a wood like Black Spruce or
pine. Spars need to have excellent grain orientation, but species
isn't important, even in the aircraft trade they use these secondary
species as long as the material is destruction tested, and graded.
So Bruce is right about his HD approach. In my experience go for the
2x10 or 12, look for ones with pith centers, their edges will be
quarter sawn you can break that wood out with a skill saw. The main
thing is that the pith be fairly centered. You can get long pices
for what a single bft would cost. Like opne 2x12 might yield two
2x5s.
Quatersawn is just a grain orientation, so if you resaw flatsawn, and
rotate 90 degrees you have quartered wood. It depends the exact
dimensions you need, but it is almost always cheaper to start with
flatsawn. There are certain species that have spectacular QS, and
you are probably not going to find flatsaw at a yard in pieces you
could resaw youself for something like a door panel. That is the
kind of situation where you need to pay the big buck for QS wood.
But for structural, it isn't the best way to go.
Scarfs actualy strengthen the wood, it's baiscaly a form of
lamination. Piver multihull spars where made by cutting 2x wood into
short sections with long scarfs, and assembling them with the scarf
orientations opposed, so that 2 2x6s yielded 1 4x6 with lots of
scarfs. The masts were very stiff.
I think a selective glassing at the deck is likely to make maters
worse, unless you are glassing the whole spar (great idea). But
assuming you aren't, what yo need is probably either solid blocking
in a hollow spar, or if the spar is solid, you don't need anything at
all. If I was going to do something external, it would probably be a
modest amount of wood lamination.to reduce crusing.
If you are making a solid pole, the end result isn't going to be
quartered, except in one plane, so assembling that pole out of
quartered wood would be very stupid.
Most Bolger unstayed rigs put the aft of the spar under tension, that
is the only place you need the really good stuff, put your best piece
there.
Great wood is straight perfect fine grain in a superior species like
SS. Good wood is nice straight stuff in a wood like Black Spruce or
pine. Spars need to have excellent grain orientation, but species
isn't important, even in the aircraft trade they use these secondary
species as long as the material is destruction tested, and graded.
So Bruce is right about his HD approach. In my experience go for the
2x10 or 12, look for ones with pith centers, their edges will be
quarter sawn you can break that wood out with a skill saw. The main
thing is that the pith be fairly centered. You can get long pices
for what a single bft would cost. Like opne 2x12 might yield two
2x5s.
Quatersawn is just a grain orientation, so if you resaw flatsawn, and
rotate 90 degrees you have quartered wood. It depends the exact
dimensions you need, but it is almost always cheaper to start with
flatsawn. There are certain species that have spectacular QS, and
you are probably not going to find flatsaw at a yard in pieces you
could resaw youself for something like a door panel. That is the
kind of situation where you need to pay the big buck for QS wood.
But for structural, it isn't the best way to go.
Scarfs actualy strengthen the wood, it's baiscaly a form of
lamination. Piver multihull spars where made by cutting 2x wood into
short sections with long scarfs, and assembling them with the scarf
orientations opposed, so that 2 2x6s yielded 1 4x6 with lots of
scarfs. The masts were very stiff.
I think a selective glassing at the deck is likely to make maters
worse, unless you are glassing the whole spar (great idea). But
assuming you aren't, what yo need is probably either solid blocking
in a hollow spar, or if the spar is solid, you don't need anything at
all. If I was going to do something external, it would probably be a
modest amount of wood lamination.to reduce crusing.
If you are making a solid pole, the end result isn't going to be
quartered, except in one plane, so assembling that pole out of
quartered wood would be very stupid.
Most Bolger unstayed rigs put the aft of the spar under tension, that
is the only place you need the really good stuff, put your best piece
there.
> Bear in mind, Oldshoe is only a 12 footI am pretty sure that Bolger imagines the mast will be built from
> 'low stress/low tech' boat. It doesn't
> really need an aircraft grade vertial
> grain spruce mast.
wood at the local lumberyard, selected only to avoid the most obvious
knots and checks.
Peter
--- smithriverranger wrote:
'low stress/low tech' boat. It doesn't
really need an aircraft grade vertial
grain spruce mast.
You might consider what I do, which is
to swing by the local Home Depot on the
way home from work every few days. I
take a quick peak at the top of the pile
of 2x6 lumber. About one in a hundred
of these boards turns out to be a
pretty nice and clear stick, cheap too.
With practice, you can spot candiates
for clear pieces by noticing the pattern
of the end grain.
Even a home grown sapling tree could
work for a mast. Also, though not cheap,
an aluminum tube 'schedule 40 pipe' could
serve as a mast.
If safety factor is the issue, increasing
the diameter of the mast is another
effective way to make them stronger
while still using cheap wood.
Check with Bolger by sending him a
fax and I bet he would agree.
Also note that the unstayed masts in
this design are under maximum stress
at the mast partners only. A few
wraps of epoxied fiberglass there
could probably double the ultimate
breaking point of the masts.
If you fear the worst, [your mast
breaking at just the wrong moment],
you could/should test the breaking
strength of a 'Home Depot' mast by
pulling on it with a rope in your
back yard before you bet your life
on it.
> oldshoe's main mast.Bear in mind, Oldshoe is only a 12 foot
> Where can i order some cvg sitka
> spruce or something
> like it.
'low stress/low tech' boat. It doesn't
really need an aircraft grade vertial
grain spruce mast.
You might consider what I do, which is
to swing by the local Home Depot on the
way home from work every few days. I
take a quick peak at the top of the pile
of 2x6 lumber. About one in a hundred
of these boards turns out to be a
pretty nice and clear stick, cheap too.
With practice, you can spot candiates
for clear pieces by noticing the pattern
of the end grain.
Even a home grown sapling tree could
work for a mast. Also, though not cheap,
an aluminum tube 'schedule 40 pipe' could
serve as a mast.
If safety factor is the issue, increasing
the diameter of the mast is another
effective way to make them stronger
while still using cheap wood.
Check with Bolger by sending him a
fax and I bet he would agree.
Also note that the unstayed masts in
this design are under maximum stress
at the mast partners only. A few
wraps of epoxied fiberglass there
could probably double the ultimate
breaking point of the masts.
If you fear the worst, [your mast
breaking at just the wrong moment],
you could/should test the breaking
strength of a 'Home Depot' mast by
pulling on it with a rope in your
back yard before you bet your life
on it.
Hi Jason, Try www.glen-l.com/resources/lumber-suppliers.html
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
> I can't get decent wood around here and i'm trying to find wood for
> my spars.I've had bad luck in the past with laminating poor quality
> wood. Mainly concerned with finding wood for my oldshoe's main mast.
> Don't want to scarf wood for this part of the boat so i need some
> long lengths. Where can i order some cvg sitka spruce or something
> like it. I know this is going to cost me but i'm trying for once to
> not use scraps and make a top quality boat.
> oh yeah is kiln dried wood bad for spars?
> Thanks for any help,
> Jason
>> I can't get decent wood around here and i'm trying to find wood forYou can also laminate scarfed lengths of plywood. There's nothing wrong
>> my spars.I've had bad luck in the past with laminating poor quality
>> wood. Mainly concerned with finding wood for my oldshoe's main mast.
>> Don't want to scarf wood for this part of the boat so i need some
>> long lengths.
with a box-section hollow mast. No, this is not very high on the aesthetic
triumph scale.
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
If cost is really not a consideration, contact Aircraft Spruce and Specialty
http://www.aircraftspruce.com/home.php
They sell spruce for aircraft wing spars, "made" to a very high standard and
priced accordingly (about $3.70 per board foot?). For fun I put in an RFQ
for 8 ea. 20' pcs 3/4 x 2-3/4" and got a price close to $600.
Personally, I think it's overkill for a mast, but ...
Roger
derbyrm at starband.net
http://derbyrm.mystarband.net
http://www.aircraftspruce.com/home.php
They sell spruce for aircraft wing spars, "made" to a very high standard and
priced accordingly (about $3.70 per board foot?). For fun I put in an RFQ
for 8 ea. 20' pcs 3/4 x 2-3/4" and got a price close to $600.
Personally, I think it's overkill for a mast, but ...
Roger
derbyrm at starband.net
http://derbyrm.mystarband.net
----- Original Message -----
From: "smithriverranger" <jasonstancil@...>
> I can't get decent wood around here and i'm trying to find wood for
> my spars.I've had bad luck in the past with laminating poor quality
> wood. Mainly concerned with finding wood for my oldshoe's main mast.
> Don't want to scarf wood for this part of the boat so i need some
> long lengths. Where can i order some cvg sitka spruce or something
> like it. I know this is going to cost me but i'm trying for once to
> not use scraps and make a top quality boat.
> oh yeah is kiln dried wood bad for spars?
> Thanks for any help,
> Jason
>
>
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
(978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
> Yahoo! Groups Links
>
>
>
>
>
I KNOW THAT WAREHAUSER HAS A SELECT WOOD BRAND THEY SELL AT HOME
DEPOT. I USE IT WHEN I MAKE JIGS FOR MY SAWS OR OTHER MACHINES. I
WILL WARN YOU NOW THAT IT IS EXPENSIVE! THEY HAVE MANY TYPES AND
THEY ARE ALL CLEAR AND VERY STRAIGHT.
HAVE FUN WITH THE MAST AND IF YOU DO MAKE ANY JOINTS MAKE THEM WITH
A FINGER JOINT ROUTER BIT. IT GIVE THE MOST GLUED SURFACE OF ANY
JOINT.
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
DEPOT. I USE IT WHEN I MAKE JIGS FOR MY SAWS OR OTHER MACHINES. I
WILL WARN YOU NOW THAT IT IS EXPENSIVE! THEY HAVE MANY TYPES AND
THEY ARE ALL CLEAR AND VERY STRAIGHT.
HAVE FUN WITH THE MAST AND IF YOU DO MAKE ANY JOINTS MAKE THEM WITH
A FINGER JOINT ROUTER BIT. IT GIVE THE MOST GLUED SURFACE OF ANY
JOINT.
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
> I can't get decent wood around here and i'm trying to find wood for
> my spars.I've had bad luck in the past with laminating poor quality
> wood. Mainly concerned with finding wood for my oldshoe's main mast.
> Don't want to scarf wood for this part of the boat so i need some
> long lengths. Where can i order some cvg sitka spruce or something
> like it. I know this is going to cost me but i'm trying for once to
> not use scraps and make a top quality boat.
> oh yeah is kiln dried wood bad for spars?
> Thanks for any help,
> Jason
I can't get decent wood around here and i'm trying to find wood for
my spars.I've had bad luck in the past with laminating poor quality
wood. Mainly concerned with finding wood for my oldshoe's main mast.
Don't want to scarf wood for this part of the boat so i need some
long lengths. Where can i order some cvg sitka spruce or something
like it. I know this is going to cost me but i'm trying for once to
not use scraps and make a top quality boat.
oh yeah is kiln dried wood bad for spars?
Thanks for any help,
Jason
my spars.I've had bad luck in the past with laminating poor quality
wood. Mainly concerned with finding wood for my oldshoe's main mast.
Don't want to scarf wood for this part of the boat so i need some
long lengths. Where can i order some cvg sitka spruce or something
like it. I know this is going to cost me but i'm trying for once to
not use scraps and make a top quality boat.
oh yeah is kiln dried wood bad for spars?
Thanks for any help,
Jason