Re: [bolger] Re: Aluminium masts
I have calculated the euler load on various lengths of aluminium tube of
different diameters. I have used a recent version of a Works for Windows
spreadsheet. Euler theory is commonly used to calculate the stress on end
loaded spars, which a stayed mast is.
R
different diameters. I have used a recent version of a Works for Windows
spreadsheet. Euler theory is commonly used to calculate the stress on end
loaded spars, which a stayed mast is.
R
Just recalled re an extruder that we use at work. I won't tell you
the
name of his outfit because I don't know if he'd appreciate the extra
business just now. Try to find an extrusion place far from
electronics
firms. If I recall, extrusion dies don't cost very much these days, I
think less than $1k. I'll bet if 10 Micro builders got together you
could (if one of you was a mechanical engineering type order a die,
with the size correct and a bolt rope groove or (aluminum) track
integral, and have masts made up. Of course there would be no taper.
I
have a suspicion there is something wrong with this notion, but I
don't know what.
Red Zinger uses a flagpole mast these days.
snip
the
name of his outfit because I don't know if he'd appreciate the extra
business just now. Try to find an extrusion place far from
electronics
firms. If I recall, extrusion dies don't cost very much these days, I
think less than $1k. I'll bet if 10 Micro builders got together you
could (if one of you was a mechanical engineering type order a die,
with the size correct and a bolt rope groove or (aluminum) track
integral, and have masts made up. Of course there would be no taper.
I
have a suspicion there is something wrong with this notion, but I
don't know what.
Red Zinger uses a flagpole mast these days.
snip
Greg,
Would a copy of that article do, or a loan of the magazine so that you can
read something, or do you just want to have your own?
Jim
G Carlson wrote:
Would a copy of that article do, or a loan of the magazine so that you can
read something, or do you just want to have your own?
Jim
G Carlson wrote:
> Can anyone part with this issue (26:40) covering Herreschoff's Rozinante?
>
> (There are other issues of similar interest including "Red Head" 123:58
> 124:6 114:32 and 56:38)
>
> Thanks, Gregg Carlson
>
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month year?????
----- Original Message -----
From: "G Carlson" <ghartc@...>
To: <bolger@egroups.com>
Sent: Saturday, July 01, 2000 11:31 PM
Subject: Re: [bolger] Woodenboat No. 26:40
> Can anyone part with this issue (26:40) covering Herreschoff's Rozinante?
>
> (There are other issues of similar interest including "Red Head" 123:58
> 124:6 114:32 and 56:38)
>
> Thanks, Gregg Carlson
>
>
>
> ------------------------------------------------------------------------
> Free, Unlimited Calls Anywhere!
> Visit Firetalk.com - click below.
>http://click.egroups.com/1/5479/13/_/3457/_/962512655/
> ------------------------------------------------------------------------
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> Bolger rules!!!
> - no cursing
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>
hi Guys.. Greg It is funny that you mention the aerospace Industry... I
just got Three mast ( poles) myself from my brother in law that works at a
large ( multinational) aluminum extruder.. they supply aluminum tubing for
areospace and airline manufactures ... the tubes that I got were a mixture
of aluminum-titanium-magnesium (spelling?) they were seconds that were going
for scrap. they are 28 feet long- 3 1/2 inches in diameter- and .132 walls.
they were suppose to be .125, that is why they were heading for the scrap
pile... I paid 120 bucks for all three ( one dollar a pound) I sold one to
Dave Gray for "foolhardy" and am keeping the other two for my Light Schooner
( when I get aroung to building it)
just got Three mast ( poles) myself from my brother in law that works at a
large ( multinational) aluminum extruder.. they supply aluminum tubing for
areospace and airline manufactures ... the tubes that I got were a mixture
of aluminum-titanium-magnesium (spelling?) they were seconds that were going
for scrap. they are 28 feet long- 3 1/2 inches in diameter- and .132 walls.
they were suppose to be .125, that is why they were heading for the scrap
pile... I paid 120 bucks for all three ( one dollar a pound) I sold one to
Dave Gray for "foolhardy" and am keeping the other two for my Light Schooner
( when I get aroung to building it)
----- Original Message -----
From: "G Carlson" <ghartc@...>
To: <bolger@egroups.com>
Sent: Saturday, July 01, 2000 11:28 PM
Subject: Re: [bolger] Re: Aluminium masts
> You're right, "brittle" is overstated, 2024-T6 and 6061-T6 are good stuff.
> So, probably, are 6063 and 7075.
>
> I believe the flag poles are anodized, or available with. I think, in
> practice, you'll probably take what you can get - no choice at all on
> flagpole materials. In fact, the scope and properties across vendors were
> so identical there's probably a single manufacturer.
>
> I was really surprised actually by the scarcity and expense of precision
> tubing, and there's a fair amount of aerospace acitivity here (Tulsa, OK).
>
> Anyway, my spars have been excellent - light, hollow - less windage and
> weight aloft, but there's been little relative interest in doing it this
> way, for some reason. Oh well.
>
> As an aside, I am have been looking for a trapeze set to set off the
> scooner's main mast - should be fun.
>
> Gregg Carlson
>
>
> >--- Inbolger@egroups.com, GHC <ghartc@p...> wrote:
> >> snip
> >> T6 is a common temper, but is, of course brittle.
> >Depends on what you mean by brittle. Of course if you do all sorts of
> >forming it will crack, but I think in use it probably won't. I have a
> >25 year old bicycle frame from 6061 T6 (tempered after welding) that
> >has been crashed at least twice without damage (to the frame, I'm not
> >talking about me or the wheels).
> >
> >I suspect you need to consider corrosion properties of different
> >alloys. I recall that 2024 is not so great for this, and that there
> >are specific marine alloys.
> >
> >
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Can anyone part with this issue (26:40) covering Herreschoff's Rozinante?
(There are other issues of similar interest including "Red Head" 123:58
124:6 114:32 and 56:38)
Thanks, Gregg Carlson
(There are other issues of similar interest including "Red Head" 123:58
124:6 114:32 and 56:38)
Thanks, Gregg Carlson
You're right, "brittle" is overstated, 2024-T6 and 6061-T6 are good stuff.
So, probably, are 6063 and 7075.
I believe the flag poles are anodized, or available with. I think, in
practice, you'll probably take what you can get - no choice at all on
flagpole materials. In fact, the scope and properties across vendors were
so identical there's probably a single manufacturer.
I was really surprised actually by the scarcity and expense of precision
tubing, and there's a fair amount of aerospace acitivity here (Tulsa, OK).
Anyway, my spars have been excellent - light, hollow - less windage and
weight aloft, but there's been little relative interest in doing it this
way, for some reason. Oh well.
As an aside, I am have been looking for a trapeze set to set off the
scooner's main mast - should be fun.
Gregg Carlson
So, probably, are 6063 and 7075.
I believe the flag poles are anodized, or available with. I think, in
practice, you'll probably take what you can get - no choice at all on
flagpole materials. In fact, the scope and properties across vendors were
so identical there's probably a single manufacturer.
I was really surprised actually by the scarcity and expense of precision
tubing, and there's a fair amount of aerospace acitivity here (Tulsa, OK).
Anyway, my spars have been excellent - light, hollow - less windage and
weight aloft, but there's been little relative interest in doing it this
way, for some reason. Oh well.
As an aside, I am have been looking for a trapeze set to set off the
scooner's main mast - should be fun.
Gregg Carlson
>--- Inbolger@egroups.com, GHC <ghartc@p...> wrote:
>> snip
>> T6 is a common temper, but is, of course brittle.
>Depends on what you mean by brittle. Of course if you do all sorts of
>forming it will crack, but I think in use it probably won't. I have a
>25 year old bicycle frame from 6061 T6 (tempered after welding) that
>has been crashed at least twice without damage (to the frame, I'm not
>talking about me or the wheels).
>
>I suspect you need to consider corrosion properties of different
>alloys. I recall that 2024 is not so great for this, and that there
>are specific marine alloys.
>
>
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--- Inbolger@egroups.com, GHC <ghartc@p...> wrote:
forming it will crack, but I think in use it probably won't. I have a
25 year old bicycle frame from 6061 T6 (tempered after welding) that
has been crashed at least twice without damage (to the frame, I'm not
talking about me or the wheels).
I suspect you need to consider corrosion properties of different
alloys. I recall that 2024 is not so great for this, and that there
are specific marine alloys.
> snipDepends on what you mean by brittle. Of course if you do all sorts of
> T6 is a common temper, but is, of course brittle.
forming it will crack, but I think in use it probably won't. I have a
25 year old bicycle frame from 6061 T6 (tempered after welding) that
has been crashed at least twice without damage (to the frame, I'm not
talking about me or the wheels).
I suspect you need to consider corrosion properties of different
alloys. I recall that 2024 is not so great for this, and that there
are specific marine alloys.
Oh yeah, the higher temper the higher strength. 6061-T0 is 18,000 psi
yield strength and -T6 is 45,000. Actually 2024 is better stuff 2024-T0 is
27,000 psi and -T6 is 69,000 psi. You can use the mast programs on the
carlsondesign.com website and figure the psi load under various
configurations and estimate your safety factor. By the way, I find
strengths of Douglas Fir at about 14,000 max. most other woods a little less
T6 is a common temper, but is, of course brittle. So, they will form (e.g.
tapering) at the lowest (annealed) temper because it's easiest on the the
tooling and energy budget. Then, they will temper. I think my flagpoles
were tempered 2024.
My poles are pretty thick - about .125 wall, thicker at the top. The loads
on poles are really similar to masts - they are rated in mph windload vs.
flag size. You might guess they go up to about 100 or 120 mph, so, all in
all, it's a roughly similar solution to a similar problem. In other words,
if you just traded a (free-standing) mast with an engineered flagpole of
similar length, you are not going to be far off.
My light schooner masts were wooden, 3.5" diameter. The 16' flagpoles I
wanted to use were either 3" or 2-7/8" O.D. If you play with the programs,
you'll see the wooden mast is a just little stronger, or that it has a
larger factor of safety. However, you have got to admit that aluminum is a
lot more uniform material than knotty old 2x4's, so I considered it a wash.
Plus, I was also willing to take the chance of buckling a $200 pole. In
practice, it has worked great in all kind of wind, and yes, you can see
them bend a little.
Of course, two things to consider - give the tubing some protection around
the mast partners, because it wants to buckle there. And, don't drill any
holes near the partners that will start a crack. In truth, the pole mast
with a little heliarcing might be ideal.
I thought about a straight tube with a 4' turned wood taper on top, but
finding precision Al. tubing is harder than finding flagpoles. And, al.
conduit is worthless.
GHC
At 05:20 PM 7/1/2000 -0500, you wrote:
yield strength and -T6 is 45,000. Actually 2024 is better stuff 2024-T0 is
27,000 psi and -T6 is 69,000 psi. You can use the mast programs on the
carlsondesign.com website and figure the psi load under various
configurations and estimate your safety factor. By the way, I find
strengths of Douglas Fir at about 14,000 max. most other woods a little less
T6 is a common temper, but is, of course brittle. So, they will form (e.g.
tapering) at the lowest (annealed) temper because it's easiest on the the
tooling and energy budget. Then, they will temper. I think my flagpoles
were tempered 2024.
My poles are pretty thick - about .125 wall, thicker at the top. The loads
on poles are really similar to masts - they are rated in mph windload vs.
flag size. You might guess they go up to about 100 or 120 mph, so, all in
all, it's a roughly similar solution to a similar problem. In other words,
if you just traded a (free-standing) mast with an engineered flagpole of
similar length, you are not going to be far off.
My light schooner masts were wooden, 3.5" diameter. The 16' flagpoles I
wanted to use were either 3" or 2-7/8" O.D. If you play with the programs,
you'll see the wooden mast is a just little stronger, or that it has a
larger factor of safety. However, you have got to admit that aluminum is a
lot more uniform material than knotty old 2x4's, so I considered it a wash.
Plus, I was also willing to take the chance of buckling a $200 pole. In
practice, it has worked great in all kind of wind, and yes, you can see
them bend a little.
Of course, two things to consider - give the tubing some protection around
the mast partners, because it wants to buckle there. And, don't drill any
holes near the partners that will start a crack. In truth, the pole mast
with a little heliarcing might be ideal.
I thought about a straight tube with a 4' turned wood taper on top, but
finding precision Al. tubing is harder than finding flagpoles. And, al.
conduit is worthless.
GHC
At 05:20 PM 7/1/2000 -0500, you wrote:
>Gregg, Ed says: "Sch 40 is high-temper 6061, harder than flagpoles.", do you
>think that's relevant? I would use wood for the gaff & boom jaws, but wear
>would be still be an issue.
>
>Is the load on a mast that much more than the load on a flagpole? You said
>you wrote a program that determined that wood was stiffer, but that the
>aluminum flagpole masts on your schooner (obligatoryBolger reference) were
>strong enough. Has this been born out in real world testing?
>
>When I looked at your masts, it seemed they were awfull thin, just how thick
>are they? 1/8inch, 14 gauge?
>
>On these tapered flagpoles, the walls on the top are thicker than on the
>bottom, probably because they take a tube and role the taper in. This would
>seem to me to indicate the weight on the top of the tapered mast is the same
>as the weight of the untapered pipe. With this in mind, would it be cheaper
>to just buy aluminum tubing of the appropriate diameter and not worry about
>the taper?
>
>Wonder if your local flagpole company would sell a strait tube?
>
>----- Original Message -----
>From: "GHC" <ghartc@...>
>To: <bolger@egroups.com>
>Sent: Saturday, July 01, 2000 4:48 PM
>Subject: Re: [bolger] Aluminium masts
>
>
>> I ordered two tapered flag poles from a local flag shop for my light
>> scooner. I believe they were 16 footers, but if you needed them fatter,
>> you could order 20's and cut the tips off - etc. About $200 each.
>>
>> Gregg Carlson
>>http://www.carlsondesign.com/lscooner.html
>>
>> At 03:59 PM 7/1/2000 -0500, you wrote:
>> >I'm considering the same mod for Entropy.
>> >
>> >> much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder
>than
>> >> flagpoles.
>> >>
>> >> ED HAILE
>
>
>
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>
Gregg, Ed says: "Sch 40 is high-temper 6061, harder than flagpoles.", do you
think that's relevant? I would use wood for the gaff & boom jaws, but wear
would be still be an issue.
Is the load on a mast that much more than the load on a flagpole? You said
you wrote a program that determined that wood was stiffer, but that the
aluminum flagpole masts on your schooner (obligatoryBolger reference) were
strong enough. Has this been born out in real world testing?
When I looked at your masts, it seemed they were awfull thin, just how thick
are they? 1/8inch, 14 gauge?
On these tapered flagpoles, the walls on the top are thicker than on the
bottom, probably because they take a tube and role the taper in. This would
seem to me to indicate the weight on the top of the tapered mast is the same
as the weight of the untapered pipe. With this in mind, would it be cheaper
to just buy aluminum tubing of the appropriate diameter and not worry about
the taper?
Wonder if your local flagpole company would sell a strait tube?
think that's relevant? I would use wood for the gaff & boom jaws, but wear
would be still be an issue.
Is the load on a mast that much more than the load on a flagpole? You said
you wrote a program that determined that wood was stiffer, but that the
aluminum flagpole masts on your schooner (obligatoryBolger reference) were
strong enough. Has this been born out in real world testing?
When I looked at your masts, it seemed they were awfull thin, just how thick
are they? 1/8inch, 14 gauge?
On these tapered flagpoles, the walls on the top are thicker than on the
bottom, probably because they take a tube and role the taper in. This would
seem to me to indicate the weight on the top of the tapered mast is the same
as the weight of the untapered pipe. With this in mind, would it be cheaper
to just buy aluminum tubing of the appropriate diameter and not worry about
the taper?
Wonder if your local flagpole company would sell a strait tube?
----- Original Message -----
From: "GHC" <ghartc@...>
To: <bolger@egroups.com>
Sent: Saturday, July 01, 2000 4:48 PM
Subject: Re: [bolger] Aluminium masts
> I ordered two tapered flag poles from a local flag shop for my light
> scooner. I believe they were 16 footers, but if you needed them fatter,
> you could order 20's and cut the tips off - etc. About $200 each.
>
> Gregg Carlson
>http://www.carlsondesign.com/lscooner.html
>
> At 03:59 PM 7/1/2000 -0500, you wrote:
> >I'm considering the same mod for Entropy.
> >
> >> much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder
than
> >> flagpoles.
> >>
> >> ED HAILE
I ordered two tapered flag poles from a local flag shop for my light
scooner. I believe they were 16 footers, but if you needed them fatter,
you could order 20's and cut the tips off - etc. About $200 each.
Gregg Carlson
http://www.carlsondesign.com/lscooner.html
At 03:59 PM 7/1/2000 -0500, you wrote:
scooner. I believe they were 16 footers, but if you needed them fatter,
you could order 20's and cut the tips off - etc. About $200 each.
Gregg Carlson
http://www.carlsondesign.com/lscooner.html
At 03:59 PM 7/1/2000 -0500, you wrote:
>I'm considering the same mod for Entropy.
>
>Where did you get your Sch 40 3-1/2" at?
>Is it tapered at all? (not really that important)
>How long was your mast, and how much does it weigh?
>How much did it cost?
>
>
>----- Original Message -----
>From: "edward haile" <ewhaile@...>
>To: <bolger@egroups.com>
>Sent: Saturday, July 01, 2000 3:51 PM
>Subject: Re: [bolger] Aluminium masts
>
>
>> Daniel,
>>
>> I chucked my old Doug fir mast on my Martha Jane for Schedule 40 aluminum.
>I
>> am very pleased with the result. It is a substantial weight-saving aloft,
>> hence a vast improvement in stability and performance. In yr case, the
>cost
>> savings should also be big. My spar diam is 3-1/2" (89mm), but you could
>go
>> much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder than
>> flagpoles.
>>
>> ED HAILE
>>
>>
>> >From: <daniel.curnutte@...>
>> >Reply-To:bolger@egroups.com
>> >To:bolger@egroups.com
>> >Subject: [bolger] Aluminium masts
>> >Date: Wed, 28 Jun 2000 16:06:29 +0000
>> >
>> >
>> >
>> >My source for Douglas Fir fell through... I have checked with local
>> >professional
>> >boat builders who confirm that they use Douglas Fir in the UK but because
>> >we
>> >have to import it from USA it is quite to very expensive. Best quote
>US$340
>> >for
>> >enough wood for masts and spars.
>> >I have started trying to find aluminium tube of the right length as an
>> >alternative for the masts leaving just the sprits to form out of wood.
>> >Has anybody out there tried an aluminium mast on a Bolger boat or even a
>> >Micro?
>> >What diameter should I use? What gauge (wall thickness) should I use? I
>am
>> >going
>> >for an un-tapered pole for the sake of cost.
>> >The spec I have given the supplier (awaiting price) is:
>> >Main - 76mm Diameter, 3.2mm gauge, 7m length
>> >Mizzen - 64mm diameter, 3.2mm gauge, 5m length
>> >
>> >Regards
>> >Daniel
>> >
>> >
>>
>> ________________________________________________________________________
>> Get Your Private, Free E-mail from MSN Hotmail athttp://www.hotmail.com
>>
>>
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>>
>> Bolger rules!!!
>> - no cursing
>> - stay on topic
>> - use punctuation
>> - add your comments at the TOP and SIGN your posts
>> - add some content: send "thanks!" and "ditto!" posts off-list.
>>
>
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>
I'm considering the same mod for Entropy.
Where did you get your Sch 40 3-1/2" at?
Is it tapered at all? (not really that important)
How long was your mast, and how much does it weigh?
How much did it cost?
Where did you get your Sch 40 3-1/2" at?
Is it tapered at all? (not really that important)
How long was your mast, and how much does it weigh?
How much did it cost?
----- Original Message -----
From: "edward haile" <ewhaile@...>
To: <bolger@egroups.com>
Sent: Saturday, July 01, 2000 3:51 PM
Subject: Re: [bolger] Aluminium masts
> Daniel,
>
> I chucked my old Doug fir mast on my Martha Jane for Schedule 40 aluminum.
I
> am very pleased with the result. It is a substantial weight-saving aloft,
> hence a vast improvement in stability and performance. In yr case, the
cost
> savings should also be big. My spar diam is 3-1/2" (89mm), but you could
go
> much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder than
> flagpoles.
>
> ED HAILE
>
>
> >From: <daniel.curnutte@...>
> >Reply-To:bolger@egroups.com
> >To:bolger@egroups.com
> >Subject: [bolger] Aluminium masts
> >Date: Wed, 28 Jun 2000 16:06:29 +0000
> >
> >
> >
> >My source for Douglas Fir fell through... I have checked with local
> >professional
> >boat builders who confirm that they use Douglas Fir in the UK but because
> >we
> >have to import it from USA it is quite to very expensive. Best quote
US$340
> >for
> >enough wood for masts and spars.
> >I have started trying to find aluminium tube of the right length as an
> >alternative for the masts leaving just the sprits to form out of wood.
> >Has anybody out there tried an aluminium mast on a Bolger boat or even a
> >Micro?
> >What diameter should I use? What gauge (wall thickness) should I use? I
am
> >going
> >for an un-tapered pole for the sake of cost.
> >The spec I have given the supplier (awaiting price) is:
> >Main - 76mm Diameter, 3.2mm gauge, 7m length
> >Mizzen - 64mm diameter, 3.2mm gauge, 5m length
> >
> >Regards
> >Daniel
> >
> >
>
> ________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail athttp://www.hotmail.com
>
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>
Daniel,
I chucked my old Doug fir mast on my Martha Jane for Schedule 40 aluminum. I
am very pleased with the result. It is a substantial weight-saving aloft,
hence a vast improvement in stability and performance. In yr case, the cost
savings should also be big. My spar diam is 3-1/2" (89mm), but you could go
much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder than
flagpoles.
ED HAILE
Get Your Private, Free E-mail from MSN Hotmail athttp://www.hotmail.com
I chucked my old Doug fir mast on my Martha Jane for Schedule 40 aluminum. I
am very pleased with the result. It is a substantial weight-saving aloft,
hence a vast improvement in stability and performance. In yr case, the cost
savings should also be big. My spar diam is 3-1/2" (89mm), but you could go
much smaller, perhaps 2 or 2-1/2". Sch 40 is high-temper 6061, harder than
flagpoles.
ED HAILE
>From: <daniel.curnutte@...>________________________________________________________________________
>Reply-To:bolger@egroups.com
>To:bolger@egroups.com
>Subject: [bolger] Aluminium masts
>Date: Wed, 28 Jun 2000 16:06:29 +0000
>
>
>
>My source for Douglas Fir fell through... I have checked with local
>professional
>boat builders who confirm that they use Douglas Fir in the UK but because
>we
>have to import it from USA it is quite to very expensive. Best quote US$340
>for
>enough wood for masts and spars.
>I have started trying to find aluminium tube of the right length as an
>alternative for the masts leaving just the sprits to form out of wood.
>Has anybody out there tried an aluminium mast on a Bolger boat or even a
>Micro?
>What diameter should I use? What gauge (wall thickness) should I use? I am
>going
>for an un-tapered pole for the sake of cost.
>The spec I have given the supplier (awaiting price) is:
>Main - 76mm Diameter, 3.2mm gauge, 7m length
>Mizzen - 64mm diameter, 3.2mm gauge, 5m length
>
>Regards
>Daniel
>
>
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200628 1355EDT
Why not talk to the 'hexperts' at <dwyermasts.com>
72 y Paz Grover
"Ha`penny" WWP-19 #965
38.1529N/76.5834W
Why not talk to the 'hexperts' at <dwyermasts.com>
72 y Paz Grover
"Ha`penny" WWP-19 #965
38.1529N/76.5834W
In a message dated 06/28/2000 11:<BR16:<BR33 AM
Eastern Daylight,daniel.curnutte@...writes:> My source for
Douglas Fir fell through... I have checked with local
Wood is better. Aluminum tends to put o lot of extra weight just where these
boats don't like it. Use any species of cedar, fir or pine, Mediterranean
cypress, luaun, even apitong or lime (maybe....get some intelligence from
other builders on those last two).
Are you near Bishops Stortford? There is a timber merchant there who will
have something suitable; it is Atkins and Son as I remember. If of interest,
I'll look up contact info.
Cheers/Step
Eastern Daylight,daniel.curnutte@...writes:> My source for
Douglas Fir fell through... I have checked with local
> professionalwe
> boat builders who confirm that they use Douglas Fir in the UK but because
> have to import it from USA it is quite to very expensive. Best quoteUS$340
> forDaniel,
> enough wood for masts and spars.
> I have started trying to find aluminium tube of the right length as an
> alternative for the masts leaving just the sprits to form out of wood.
Wood is better. Aluminum tends to put o lot of extra weight just where these
boats don't like it. Use any species of cedar, fir or pine, Mediterranean
cypress, luaun, even apitong or lime (maybe....get some intelligence from
other builders on those last two).
Are you near Bishops Stortford? There is a timber merchant there who will
have something suitable; it is Atkins and Son as I remember. If of interest,
I'll look up contact info.
Cheers/Step