Re: Schedule 40 AL tubing for spars & spar weight.
--- Inbolger@yahoogroups.com, "Jeff" <boatbuilding@g...> wrote:
was special ordered and cost $93.00. I'm not sure what it weights
but it certainly not any heavier than the wooden mast for that boat.
Cost was probably 3 or 4 times that of a wooden mast but it sure is
easier to make!
aluminum for use as masts, and I am finally driven to comment.
From what I've seen used--and from personal experience--I believe you
will need stays on any mast made from aluminum pipe. The aluminum
used in pipe is soft compared to the aluminum used for flagpoles or
lightpoles and cannot resist the bending forces without stays.
On the other hand, flagpoles, though thinner walled than pipe, are
tempered aluminum and can handle the flex and compression loads at
the partners without stays. I had a Colvin designed Gazelle on which
I used two 8" diameter flagpoles for masts, unstayed. Each carried a
400 square foot lug sail, with never a problem. Colvin designed the
Gazelle to use 6" diameter pipe, with splices and stays. My 8"
diameter poles were lighter than his due to the thinner (3/16") wall
thickness.
Using poles unstayed you MUST NOT do any welding because that process
untempers the pole in the area of the weld. The only holes I put into
mine were at the very top where I through-bolted the mast head
fitting.
For what it's worth.....
> I put bought a 20' sched. 80 aluminum pipe to be used as a mast onmy Trilars. It's heavier than schedule 40 and thicker walled. It
was special ordered and cost $93.00. I'm not sure what it weights
but it certainly not any heavier than the wooden mast for that boat.
Cost was probably 3 or 4 times that of a wooden mast but it sure is
easier to make!
>I've been lurking and following this discussion of Schedule 40 and 80
> Jeff > Bolger rules!!!
aluminum for use as masts, and I am finally driven to comment.
From what I've seen used--and from personal experience--I believe you
will need stays on any mast made from aluminum pipe. The aluminum
used in pipe is soft compared to the aluminum used for flagpoles or
lightpoles and cannot resist the bending forces without stays.
On the other hand, flagpoles, though thinner walled than pipe, are
tempered aluminum and can handle the flex and compression loads at
the partners without stays. I had a Colvin designed Gazelle on which
I used two 8" diameter flagpoles for masts, unstayed. Each carried a
400 square foot lug sail, with never a problem. Colvin designed the
Gazelle to use 6" diameter pipe, with splices and stays. My 8"
diameter poles were lighter than his due to the thinner (3/16") wall
thickness.
Using poles unstayed you MUST NOT do any welding because that process
untempers the pole in the area of the weld. The only holes I put into
mine were at the very top where I through-bolted the mast head
fitting.
For what it's worth.....
> - no cursing, flaming, trolling, spamming, or flogging dead horsesposts
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred'
> - Pls add your comments at the TOP, SIGN your posts, and snip away01930, Fax: (978) 282-1349
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
> - Unsubscribe:bolger-unsubscribe@yahoogroups.comsubscribe@yahoogroups.com
> - Open discussion: bolger_coffee_lounge-
> Yahoo! Groups Links
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
My pocket ref lists 2 inch steel schedule 80 pipe at 5 lbs per linear
foot. Aluminum ought to be 1/3 as much, or about 33 lbs. That seems like
a lot, probably equivalent to a wood mast weighing 50 lbs or more
(because of the taper). Also, the aluminum mast will probably require
reefing sooner, as the top won't bend away from gusts the way a tapered
wood mast will. I just calculated, (and maybe I'm wrong), that a 20 foot
mast made from 40 lb/ft^3 wood, tapered from 3" dia to 1" dia will be 18
lbs, and if you scale up to 4" dia you will have 30 lbs. Either would be
much easier to handle due to the taper. Spruce would be lighter.
If you assume that the wood yields at 5000 psi, and the aluminum yields
at 30,000 psi (I hope both are equally optimistic), then, also assuming
I haven't messed up the calculations, the wood mast ought to take about
2600 ft-lbs at the bottom, and the aluminum one about 1800. In practice,
I'd expect them to be of equivalent strength as I imagine the aluminum
is more uniform.
Be aware that I'm a little rusty and had to go over the numbers a few
times. I have more confidence in the relative proportion of the numbers
than in their absolute values.
I just looked at a drawing of Trilars and I suspect that both the 4"
wood and 2" (nominal, really 2.375") aluminum mast are massive overkill.
Brick uses a mast of a similar height (15'9")and a similar sail and gets
away with a 2 1/4" width at the bottomt, tho I admit it's square at the
bottom. Brick is a very stable boat, and we've shown that Brick can take
at least 20mph (I'd guess 25mph in gusts) of wind without damage, even
with little knots in the mast. It does creak alarmingly! A 3" mast ought
to be well over twice as strong. I'd be surprised if something else
didn't break first.
You don't really have to carry more mast than it takes to sink one of
the floats, though I don't know how much that is. The 4" mast ought to
sink a float displacing 500 lbs, assuming Trilars is less than 10 feet wide.
Not sure why I went to all this trouble. Probably more fun than what I'm
supposed to be doing. (The first element of all business accomplishment,
including employment, is sales. More important than substance, more
important than management skill, more important than engineering. You
just can't get started at anything without going thru the flim flam. Can
you guess I'm looking for work?)
Lincoln Ross
foot. Aluminum ought to be 1/3 as much, or about 33 lbs. That seems like
a lot, probably equivalent to a wood mast weighing 50 lbs or more
(because of the taper). Also, the aluminum mast will probably require
reefing sooner, as the top won't bend away from gusts the way a tapered
wood mast will. I just calculated, (and maybe I'm wrong), that a 20 foot
mast made from 40 lb/ft^3 wood, tapered from 3" dia to 1" dia will be 18
lbs, and if you scale up to 4" dia you will have 30 lbs. Either would be
much easier to handle due to the taper. Spruce would be lighter.
If you assume that the wood yields at 5000 psi, and the aluminum yields
at 30,000 psi (I hope both are equally optimistic), then, also assuming
I haven't messed up the calculations, the wood mast ought to take about
2600 ft-lbs at the bottom, and the aluminum one about 1800. In practice,
I'd expect them to be of equivalent strength as I imagine the aluminum
is more uniform.
Be aware that I'm a little rusty and had to go over the numbers a few
times. I have more confidence in the relative proportion of the numbers
than in their absolute values.
I just looked at a drawing of Trilars and I suspect that both the 4"
wood and 2" (nominal, really 2.375") aluminum mast are massive overkill.
Brick uses a mast of a similar height (15'9")and a similar sail and gets
away with a 2 1/4" width at the bottomt, tho I admit it's square at the
bottom. Brick is a very stable boat, and we've shown that Brick can take
at least 20mph (I'd guess 25mph in gusts) of wind without damage, even
with little knots in the mast. It does creak alarmingly! A 3" mast ought
to be well over twice as strong. I'd be surprised if something else
didn't break first.
You don't really have to carry more mast than it takes to sink one of
the floats, though I don't know how much that is. The 4" mast ought to
sink a float displacing 500 lbs, assuming Trilars is less than 10 feet wide.
Not sure why I went to all this trouble. Probably more fun than what I'm
supposed to be doing. (The first element of all business accomplishment,
including employment, is sales. More important than substance, more
important than management skill, more important than engineering. You
just can't get started at anything without going thru the flim flam. Can
you guess I'm looking for work?)
Lincoln Ross
>> My very roughly shaped wooden masts get a "How did you get themNo danger of this on any of my boats!
>> round?" everytime I go sailing.
>
>Possibly the rougher they are, the more often you get the question.
>If they are too perfect, everyone will assume they were done by
>a "pro".
--
C.E.P.
415 W.46th Street
New York, New York 10036
http://www.crumblingempire.com
Mobile (646) 325-8325
Office (212) 247-0296
> My very roughly shaped wooden masts get a "How did you get themPossibly the rougher they are, the more often you get the question.
> round?" everytime I go sailing.
If they are too perfect, everyone will assume they were done by
a "pro".
Peter
>technique and over aggressiveness with the power planer and belt sander butWhen I haven't been doing shaping for a while, I find I loose my
>everyone has a nemesis in boat building and making those darn mast is mine.
touch and take off too much material. The best solution I've come up
with is to use finer grit until I get my groove back.
YIBB,
David
--
C.E.P.
415 W.46th Street
New York, New York 10036
http://www.crumblingempire.com
Mobile (646) 325-8325
Office (212) 247-0296
Well I've made a good number of wooden masts and with the exception of the
3rd attempt on the Frolic2, I just can't make a straight mast unless it's
better than 2 inches thick at the peak. for some reason those darn things
never come out straight or nice and round. I have no doubt it's my
technique and over aggressiveness with the power planer and belt sander but
everyone has a nemesis in boat building and making those darn mast is mine.
Sanding, well most hate sanding while I can get lost in my own little world
sanding and time flies so I find sanding can be good therapy after a tough
week on the job.
Go figure...
Jeff
3rd attempt on the Frolic2, I just can't make a straight mast unless it's
better than 2 inches thick at the peak. for some reason those darn things
never come out straight or nice and round. I have no doubt it's my
technique and over aggressiveness with the power planer and belt sander but
everyone has a nemesis in boat building and making those darn mast is mine.
Sanding, well most hate sanding while I can get lost in my own little world
sanding and time flies so I find sanding can be good therapy after a tough
week on the job.
Go figure...
Jeff
----- Original Message -----
From: "David Ryan" <david@...>
To: <bolger@yahoogroups.com>
Sent: Tuesday, March 16, 2004 8:16 AM
Subject: [bolger] Re: Schedule 40 AL tubing for spars & spar weight.
> FBBB,
>
> Missing from all this discussion of aluminum masts is the plain and
> simple fact that making wood masts is one of the most enjoyable parts
> of building boats. Move over, no one is going to be impressed with
> aluminum tubes (unless you use them to concentrate fissile material.
> My very roughly shaped wooden masts get a "How did you get them
> round?" everytime I go sailing.
>
> YIBB,
>
> David
> --
>
> C.E.P.
> 415 W.46th Street
> New York, New York 10036
>http://www.crumblingempire.com
> Mobile (646) 325-8325
> Office (212) 247-0296
>
>
> 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
>
>
>
>
>
>
FBBB,
Missing from all this discussion of aluminum masts is the plain and
simple fact that making wood masts is one of the most enjoyable parts
of building boats. Move over, no one is going to be impressed with
aluminum tubes (unless you use them to concentrate fissile material.
My very roughly shaped wooden masts get a "How did you get them
round?" everytime I go sailing.
YIBB,
David
--
C.E.P.
415 W.46th Street
New York, New York 10036
http://www.crumblingempire.com
Mobile (646) 325-8325
Office (212) 247-0296
Missing from all this discussion of aluminum masts is the plain and
simple fact that making wood masts is one of the most enjoyable parts
of building boats. Move over, no one is going to be impressed with
aluminum tubes (unless you use them to concentrate fissile material.
My very roughly shaped wooden masts get a "How did you get them
round?" everytime I go sailing.
YIBB,
David
--
C.E.P.
415 W.46th Street
New York, New York 10036
http://www.crumblingempire.com
Mobile (646) 325-8325
Office (212) 247-0296
A tapered solid timber mast based on the original plan, as Bolger has
suggested for Navigator, will be lighter than schedule80. Mine,
before being cut down to 20ft was made from exceptionally dense and
heavy douglas fir, and weighed only 21kg. Shortened to 20ft and
planed a little, it came down to 16kg.
I would not like to lift out a 33kg alloy mast on the water, as I
have had to do in an emergency. The other consideration is, that the
centre of gravity of my mast is only 7'-4' from the base, whereas the
alloy one will be 10', a significant difference when the boat is
rocking and jiggling.
DonB
suggested for Navigator, will be lighter than schedule80. Mine,
before being cut down to 20ft was made from exceptionally dense and
heavy douglas fir, and weighed only 21kg. Shortened to 20ft and
planed a little, it came down to 16kg.
I would not like to lift out a 33kg alloy mast on the water, as I
have had to do in an emergency. The other consideration is, that the
centre of gravity of my mast is only 7'-4' from the base, whereas the
alloy one will be 10', a significant difference when the boat is
rocking and jiggling.
DonB
--- Inbolger@yahoogroups.com, "Jeff" <boatbuilding@g...> wrote:
> I put bought a 20' sched. 80 aluminum pipe to be used as a mast on
my Trilars. It's heavier than schedule 40 and thicker walled. It
was special ordered and cost $93.00. I'm not sure what it weights
but it certainly not any heavier than the wooden mast for that boat.
Cost was probably 3 or 4 times that of a wooden mast but it sure is
easier to make!
>
> Jeff
>
> ----- Original Message -----
> From: Derek Waters
> To:bolger@yahoogroups.com
> Sent: Friday, March 12, 2004 3:07 PM
> Subject: Re: [bolger] Schedule 40 AL tubing for spars & spar
weight.
>
>
> [ Mast length x mast diameter x density of chosen material ]
minus [density
> x volume removed from core if hollow ]
>
> Wood being a natural product varies in its weight but the USDAFS
gives Doug
> Fir's SG as about 0.45 to 0.5; Western Red Cedar as about 0.3;
Sitka Spruce
> as about 0.35.
>
> Sched. 40 sizes are nominal. 2" diameter Sched. 40 is 2 and three
eighths
> diameter and weighs about a pound and a quarter per running foot.
Oldshoe's
> mainmast is what, 20 feet? 25 lbs.
> 2.5" nominal is over two pounds per foot.
>
> I don't have the figures to hand, but my [Bolger OK'd] wooden
Micro main
> mast is thirty-odd pounds rigged. The Sched. 40 called for in the
plans
> weighed in at over 60lbs bare. It was also ruinously expensive to
obtain
> locally.
>
> YMMV
> cheers
> Derek
>
>
>
> 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
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
Oh the things a guy will do to get his boat launched.....
Rick
Bruce Hallman wrote:
Rick
Bruce Hallman wrote:
>[Non-text portions of this message have been removed]
>
> So, I plan to saw up one testosterone/
> bikini jet boat hull this evening,
> ...could be fun!
>
>
Don't trust your spell checker!
"steam heating return piping, highway signs, and contraction."
It should be "construction". But I spell worse than my spell checker guesses so it's probably an even bet.
Jeff
"steam heating return piping, highway signs, and contraction."
It should be "construction". But I spell worse than my spell checker guesses so it's probably an even bet.
Jeff
----- Original Message -----
From: Jeff
To:bolger@yahoogroups.com
Sent: Monday, March 15, 2004 11:21 AM
Subject: Re: [bolger] Schedule 40 AL tubing for spars & spar weight.
Mine was 2" diameter and I just went down to the local steel supplier. We have a local retail steel place that does metal recycling as well as selling new steel. He carried the schedule 40 but had to order the 80 which took a week to show up.
It doesn't surprise me the difference in price because a 4 inch pipe is certainly double the material and shipping cost, and probably a less common size than the 2 inch which is used a lot in steam heating return piping, highway signs, and contraction.
Jeff
----- Original Message -----
From: Bruce Hallman
To:bolger@yahoogroups.com
Sent: Monday, March 15, 2004 10:42 AM
Subject: Re: [bolger] Schedule 40 AL tubing for spars & spar weight.
--- Jeff <boatbuilding@...> wrote:
> I put bought a 20' sched. 80 aluminum pipe to be
> used as a mast on my Trilars. It's heavier than
> schedule 40 and thicker walled. It was special
> ordered and cost $93.00.
Wow, I was quoted $20 per foot for
4" diameter schedule 40 aluminum tube.
IE $400 versus $93.00 !?!?!?
What diameter was yours? How
did you special order it?
============
BTW, I got two quotes $300 and
$150 to junk my jet boat hulk.
I figure I can chop it up with my
Skilsaw and dump it in pieces
for $55.
So, I plan to saw up one testosterone/
bikini jet boat hull this evening,
...could be fun!
Seeing it side by side next to Micro
Navigator in my driveway is a real
study in contrasts.
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
[Non-text portions of this message have been removed]
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
[Non-text portions of this message have been removed]
Mine was 2" diameter and I just went down to the local steel supplier. We have a local retail steel place that does metal recycling as well as selling new steel. He carried the schedule 40 but had to order the 80 which took a week to show up.
It doesn't surprise me the difference in price because a 4 inch pipe is certainly double the material and shipping cost, and probably a less common size than the 2 inch which is used a lot in steam heating return piping, highway signs, and contraction.
Jeff
It doesn't surprise me the difference in price because a 4 inch pipe is certainly double the material and shipping cost, and probably a less common size than the 2 inch which is used a lot in steam heating return piping, highway signs, and contraction.
Jeff
----- Original Message -----
From: Bruce Hallman
To:bolger@yahoogroups.com
Sent: Monday, March 15, 2004 10:42 AM
Subject: Re: [bolger] Schedule 40 AL tubing for spars & spar weight.
--- Jeff <boatbuilding@...> wrote:
> I put bought a 20' sched. 80 aluminum pipe to be
> used as a mast on my Trilars. It's heavier than
> schedule 40 and thicker walled. It was special
> ordered and cost $93.00.
Wow, I was quoted $20 per foot for
4" diameter schedule 40 aluminum tube.
IE $400 versus $93.00 !?!?!?
What diameter was yours? How
did you special order it?
============
BTW, I got two quotes $300 and
$150 to junk my jet boat hulk.
I figure I can chop it up with my
Skilsaw and dump it in pieces
for $55.
So, I plan to saw up one testosterone/
bikini jet boat hull this evening,
...could be fun!
Seeing it side by side next to Micro
Navigator in my driveway is a real
study in contrasts.
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
[Non-text portions of this message have been removed]
--- Jeff <boatbuilding@...> wrote:
4" diameter schedule 40 aluminum tube.
IE $400 versus $93.00 !?!?!?
What diameter was yours? How
did you special order it?
============
BTW, I got two quotes $300 and
$150 to junk my jet boat hulk.
I figure I can chop it up with my
Skilsaw and dump it in pieces
for $55.
So, I plan to saw up one testosterone/
bikini jet boat hull this evening,
...could be fun!
Seeing it side by side next to Micro
Navigator in my driveway is a real
study in contrasts.
> I put bought a 20' sched. 80 aluminum pipe to beWow, I was quoted $20 per foot for
> used as a mast on my Trilars. It's heavier than
> schedule 40 and thicker walled. It was special
> ordered and cost $93.00.
4" diameter schedule 40 aluminum tube.
IE $400 versus $93.00 !?!?!?
What diameter was yours? How
did you special order it?
============
BTW, I got two quotes $300 and
$150 to junk my jet boat hulk.
I figure I can chop it up with my
Skilsaw and dump it in pieces
for $55.
So, I plan to saw up one testosterone/
bikini jet boat hull this evening,
...could be fun!
Seeing it side by side next to Micro
Navigator in my driveway is a real
study in contrasts.
I put bought a 20' sched. 80 aluminum pipe to be used as a mast on my Trilars. It's heavier than schedule 40 and thicker walled. It was special ordered and cost $93.00. I'm not sure what it weights but it certainly not any heavier than the wooden mast for that boat. Cost was probably 3 or 4 times that of a wooden mast but it sure is easier to make!
Jeff
Jeff
----- Original Message -----
From: Derek Waters
To:bolger@yahoogroups.com
Sent: Friday, March 12, 2004 3:07 PM
Subject: Re: [bolger] Schedule 40 AL tubing for spars & spar weight.
[ Mast length x mast diameter x density of chosen material ] minus [density
x volume removed from core if hollow ]
Wood being a natural product varies in its weight but the USDAFS gives Doug
Fir's SG as about 0.45 to 0.5; Western Red Cedar as about 0.3; Sitka Spruce
as about 0.35.
Sched. 40 sizes are nominal. 2" diameter Sched. 40 is 2 and three eighths
diameter and weighs about a pound and a quarter per running foot. Oldshoe's
mainmast is what, 20 feet? 25 lbs.
2.5" nominal is over two pounds per foot.
I don't have the figures to hand, but my [Bolger OK'd] wooden Micro main
mast is thirty-odd pounds rigged. The Sched. 40 called for in the plans
weighed in at over 60lbs bare. It was also ruinously expensive to obtain
locally.
YMMV
cheers
Derek
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
[Non-text portions of this message have been removed]
To add to Dereks- Bolger replied to me with the following-
He picked aluminium to save weight....not always the case, see below.
Main mast 100x6mm schedule 40 (low grade uneven wall thickness
aluminium)
Mizzen 63x5mm aluminium
gaff, boom 50x3mm aluminium
He said thinner walls could be tried at some risk.
If timber he said similar sizes to above, but with a hollow to
eliminate checking.
I adapted my micro mast which he also suggested, which is d'fir,
slightly hollowed.
aluminium mast 33kg
original micro 21kg
modified original 16kg (if it stays up!)
He is inclined to think fibreglass battens as best.
Micro Oink - I have strengthened the keel/hull join with a triangular
timber fillet, followed by a coved scallop and diagonal rove tape -
see this group, Photos, Micro to.....
DonB
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
He picked aluminium to save weight....not always the case, see below.
Main mast 100x6mm schedule 40 (low grade uneven wall thickness
aluminium)
Mizzen 63x5mm aluminium
gaff, boom 50x3mm aluminium
He said thinner walls could be tried at some risk.
If timber he said similar sizes to above, but with a hollow to
eliminate checking.
I adapted my micro mast which he also suggested, which is d'fir,
slightly hollowed.
aluminium mast 33kg
original micro 21kg
modified original 16kg (if it stays up!)
He is inclined to think fibreglass battens as best.
Micro Oink - I have strengthened the keel/hull join with a triangular
timber fillet, followed by a coved scallop and diagonal rove tape -
see this group, Photos, Micro to.....
DonB
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
wrote:
> Thanks for the info on the spar diameters.building
>
> As far as that other comment goes, i take a bit of offense.
> I worked as a carpenter through college and had no problems
> houses.mast
> I could go buy another boat, but what i want is not out there.
> I had no problems with the other 4 boats i build in the last 2.5
> years. They all floated just fine :) Besides it's relaxing at the
> end ofa long day.
> The old shoe is 12' long and weighs about 600 lbs a birds mouth
> is'nt needed. Besides i can rip, laminate and shape a solid mast in
> less than a day. Where as a birdsmouth would take me 4 times that
> long....i don't know i don't want to find out either.
>
> Thanks again for those diameters
> Jason Stancil
Thanks for the info on the spar diameters.
As far as that other comment goes, i take a bit of offense.
I worked as a carpenter through college and had no problems building
houses.
I could go buy another boat, but what i want is not out there.
I had no problems with the other 4 boats i build in the last 2.5
years. They all floated just fine :) Besides it's relaxing at the
end ofa long day.
The old shoe is 12' long and weighs about 600 lbs a birds mouth mast
is'nt needed. Besides i can rip, laminate and shape a solid mast in
less than a day. Where as a birdsmouth would take me 4 times that
long....i don't know i don't want to find out either.
Thanks again for those diameters
Jason Stancil
As far as that other comment goes, i take a bit of offense.
I worked as a carpenter through college and had no problems building
houses.
I could go buy another boat, but what i want is not out there.
I had no problems with the other 4 boats i build in the last 2.5
years. They all floated just fine :) Besides it's relaxing at the
end ofa long day.
The old shoe is 12' long and weighs about 600 lbs a birds mouth mast
is'nt needed. Besides i can rip, laminate and shape a solid mast in
less than a day. Where as a birdsmouth would take me 4 times that
long....i don't know i don't want to find out either.
Thanks again for those diameters
Jason Stancil
PB&F specify 4 inch diameter for the Micro Navigator main mast, 3 inch for
the mizzen.
Oink is Don Baldwinson's boat; I agree, he's doing a nice job.
IMO, if you do not have the 'patience' to build a birdsmouth mast you may
find building your own boat a little taxing.
cheers
Derek
the mizzen.
Oink is Don Baldwinson's boat; I agree, he's doing a nice job.
IMO, if you do not have the 'patience' to build a birdsmouth mast you may
find building your own boat a little taxing.
cheers
Derek
Thanks derek for the info....what diameter did bolger specify for
your mast? I'm assuming this was for the navigator conversion.? Are
you the owner of oink?....nice boat. Trying to figure what diameter
i could get away with. If i can go with 1.5" i'm sold on 40 tubing
anodized black, if i have to go with 2" i'll most likely go with a
solid spruce stick......not even interested in a bird's mouth mast i
don't have that much patience.
Thanks,
Jason Stancil
your mast? I'm assuming this was for the navigator conversion.? Are
you the owner of oink?....nice boat. Trying to figure what diameter
i could get away with. If i can go with 1.5" i'm sold on 40 tubing
anodized black, if i have to go with 2" i'll most likely go with a
solid spruce stick......not even interested in a bird's mouth mast i
don't have that much patience.
Thanks,
Jason Stancil
[ Mast length x mast diameter x density of chosen material ] minus [density
x volume removed from core if hollow ]
Wood being a natural product varies in its weight but the USDAFS gives Doug
Fir's SG as about 0.45 to 0.5; Western Red Cedar as about 0.3; Sitka Spruce
as about 0.35.
Sched. 40 sizes are nominal. 2" diameter Sched. 40 is 2 and three eighths
diameter and weighs about a pound and a quarter per running foot. Oldshoe's
mainmast is what, 20 feet? 25 lbs.
2.5" nominal is over two pounds per foot.
I don't have the figures to hand, but my [Bolger OK'd] wooden Micro main
mast is thirty-odd pounds rigged. The Sched. 40 called for in the plans
weighed in at over 60lbs bare. It was also ruinously expensive to obtain
locally.
YMMV
cheers
Derek
x volume removed from core if hollow ]
Wood being a natural product varies in its weight but the USDAFS gives Doug
Fir's SG as about 0.45 to 0.5; Western Red Cedar as about 0.3; Sitka Spruce
as about 0.35.
Sched. 40 sizes are nominal. 2" diameter Sched. 40 is 2 and three eighths
diameter and weighs about a pound and a quarter per running foot. Oldshoe's
mainmast is what, 20 feet? 25 lbs.
2.5" nominal is over two pounds per foot.
I don't have the figures to hand, but my [Bolger OK'd] wooden Micro main
mast is thirty-odd pounds rigged. The Sched. 40 called for in the plans
weighed in at over 60lbs bare. It was also ruinously expensive to obtain
locally.
YMMV
cheers
Derek
--- Inbolger@yahoogroups.com, "smithriverranger" <jasonstancil@h...>
hardware and lines. I expect OLDSHOE could easily be 10 lb lighter.
This is about the time in the discussion where birdsmouth
construction comes up. I believe PCB feels it is a good construction
method. Not that I want to get involved meself;-)
Cheers, Nels
> I'm trying to figure out wooden mast weight but all i have is a 11'mast
> 2" rd. tapered to 1" round. so it kinda dinky in comparison to what
> i'm now looking for now.........Do you micro(more importantly
> oldshoe) owners know with some degree of accuracy how much your
> weighs?Lestat's (Eastern Spruce) mast (MICRO) weighs 36 lb with all it's
hardware and lines. I expect OLDSHOE could easily be 10 lb lighter.
This is about the time in the discussion where birdsmouth
construction comes up. I believe PCB feels it is a good construction
method. Not that I want to get involved meself;-)
Cheers, Nels
Somebody brought this up in the CVG thread(thanks to all for the
info) I looked into this stuff and it looks to be realitively light,
available in a multitude of sizes, can be anodized brown or blonde
to look like wood(if you're into that), can be purchaced in 24'
lengths and realitively cheap.
I'm trying to figure out wooden mast weight but all i have is a 11'
2" rd. tapered to 1" round. so it kinda dinky in comparison to what
i'm now looking for now.........Do you micro(more importantly
oldshoe) owners know with some degree of accuracy how much your mast
weighs? I know it all varies my closet pole yard and boom under 9'
long made of a mystery wood weigh as much or more than my 2.5'
longer and thicker mast
Anyways, the schedule 40 tubing varies from 5.2 lbs. for a 1" x 24'
length to 22.5/lbs for a heavy duty 2" x 24' piece.
Anyone?
Thanks,
Jason Stancil
info) I looked into this stuff and it looks to be realitively light,
available in a multitude of sizes, can be anodized brown or blonde
to look like wood(if you're into that), can be purchaced in 24'
lengths and realitively cheap.
I'm trying to figure out wooden mast weight but all i have is a 11'
2" rd. tapered to 1" round. so it kinda dinky in comparison to what
i'm now looking for now.........Do you micro(more importantly
oldshoe) owners know with some degree of accuracy how much your mast
weighs? I know it all varies my closet pole yard and boom under 9'
long made of a mystery wood weigh as much or more than my 2.5'
longer and thicker mast
Anyways, the schedule 40 tubing varies from 5.2 lbs. for a 1" x 24'
length to 22.5/lbs for a heavy duty 2" x 24' piece.
Anyone?
Thanks,
Jason Stancil