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Old 28-09-2013, 12:15   #76
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Re: What wood for a bowsprit?

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Originally Posted by sabray View Post
I'll just hang out as a rogue. For this boat I would not be worried about weight. Unless your part of oracle. I'll concede, go use spruce. The advantage of spruce is weight to strength. When on a spar 50 plus feet up that can be big. In the bow of a cruising yacht it's reduced. Can we agree on that. The best wood should be more resistant to rot then spruce. Able to withstand huge compression load. it also depends on the length and ability to disassemble for service. Minaret wins the choice award. He is a better shipwright then I. In my day we used live oak for futtocks. Pitch pine or oak for planking big as fishing boats. Smaller guys got cedar planked, oak frames and black locust anywhere you yacht folk use teak today. You can tell old growth pretty quick by looking at the annual rings at the end grain. Farmed woods are even and wide spaced.

Can you at least admit that weight on the bow, particularly weight installed on a lever arm like a sprit, causes hobbyhorsing?

Not a question of "who's a better shipwright", you might make a tighter joint than I in less time. We are trying to disseminate info here, lets make it good info. Nothing terribly wrong with the methods you espouse, just consider that there might be a better way. I do actually have a degree in boat building, I've spent my whole life studying this stuff, and I've got buckets of book learnin'. Doesn't make me a better shipwright necessarily. You are probably older than me and have worked on more wood boats than me. I'm more glass guy than traditional shipwright. I win the Golden Squeegee Award every year, but that doesn't help my woodwork any!
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Old 28-09-2013, 12:19   #77
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Re: What wood for a bowsprit?

If you don't believe it's the case, try an experiment. Put an empty plastic drum in your bow pulpit as far out towards the end as you can and as big as you can and go sailing. Note how the boat pitches to the swell. Then fill the drum as much as you are comfortable doing, a few hundred lbs. worth. Now note the difference in how the boat feels. Is anyone willing to believe there will be no difference? If there is a difference, what is it? And at what point does this become an insignificant performance factor? For what boat? These are all issues which NA's have already put a lot of research into, and it is well understood stuff. Ask any NA worth his salt.
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Old 28-09-2013, 12:28   #78
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Re: What wood for a bowsprit?

Browse By Common Name | The Wood Database

I used the site above, along with you all and the Cape Dory website to replicate my old bowsprit. I really struggled with the design, it was originally a simple oak plank, which I didn't like because of the potential "slapping" of the water when she comes down off a wave. I thought it was an unnecessary strain, as the water has no where to go when it is just a big flat surface. But in the end I just replicated the darn plank shape. CDs have no issue with hobby horsing but they do have issues with weather helm so I added some length to move j measurement out a bit. This has been done by other CD30s with good success. In the end, I was very happy with it and think it is strong enough to pick up the whole darn boat

Example of some of the info on the web site

Common Name(s): Teak, Burmese Teak
Scientific Name: Tectona grandis
Distribution: Native to southern Asia, Teak is also widely grown on plantations throughout tropical regions of Africa, Asia, and Latin America.
Tree Size: 100-130 ft (30-40 m) tall, 3-5 ft (1-1.5 m) trunk diameter
Average Dried Weight: 41 lbs/ft3 (650 kg/m3)
Specific Gravity (Basic, 12% MC): .54, .65
Janka Hardness: 1,070 lbf (4,740 N)
Modulus of Rupture: 13,940 lbf/in2 (96.1 MPa)
Elastic Modulus: 1,570,000 lbf/in2 (10.83 GPa)
Crushing Strength: 7,770 lbf/in2 (53.6 MPa)
Shrinkage: Radial: 2.5%, Tangential: 5.8%, Volumetric: 7.0%, T/R Ratio: 2.3


Common Name(s): White Oak
Scientific Name: Quercus alba
Distribution: Eastern United States
Tree Size: 65-85 ft (20-25 m) tall, 3-4 ft (1-1.2 m) trunk diameter
Average Dried Weight: 50 lbs/ft3 (805 kg/m3)
Specific Gravity (Basic, 12% MC): .60, .81
Janka Hardness: 1,360 lbf (6,000 N)
Modulus of Rupture: 15,200 lbf/in2 (104.8 MPa)
Elastic Modulus: 1,780,000 lbf/in2 (12.30 GPa)
Crushing Strength: 7,440 lbf/in2 (51.3 MPa)
Shrinkage:Radial: 5.6%, Tangential: 10.5%, Volumetric: 16.3%, T/R Ratio: 1.9


Common Name(s): Cypress, Baldcypress
Scientific Name: Taxodium distichum
Distribution: Southeastern United States
Tree Size: 100 ft (30 m) tall, 3-5 ft (1-1.5 m) trunk diameter
Average Dried Weight: 33 lbs/ft3 (525 kg/m3)
Specific Gravity (Basic, 12% MC): .42, .53
Janka Hardness: 510 lbf (2,270 N)
Modulus of Rupture: 10,600 lbf/in2 (73.1 MPa)
Elastic Modulus: 1,440,000 lbf/in2 (9.93 GPa)
Crushing Strength: 6,360 lbf/in2 (43.9 MPa)
Shrinkage: Radial: 3.8%, Tangential: 6.2%, Volumetric: 10.5%, T/R Ratio: 1.6
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Old 28-09-2013, 12:57   #79
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Re: What wood for a bowsprit?

By looking at the pictures it seems the bowsprit has a stainless frame with a wooden platform. So, the OP can use any lightweight wood, even plywood would do (but not recommended for aesthetic reasons) - the frame is taking the load and the wood is just to step on.
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Old 10-04-2016, 13:31   #80
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Re: What wood for a bowsprit?

So I bought a 23' Venture Neuport, a 71. It was going to be a project boat all along. I knew the trailer needed work, specifically, I was going to cut off the whole tongue and a foot into the structure and replace tongue, possibly with a telescoping tongue, and winch and winch stand. I jumped on the trailer before the boat went on it. It seemed sound enough for one long trip.. But I was wrong. The trailer separated from the tongue along corrosion lines about 150 miles from my house while I was doing about 55 mph on a smooth straight section of the interstate. The damage I can see was a 20" by about 8" hole in the boat on the port side, just below the Waterline. And the bowsprit is broken.

It seems to be a 72" piece of wood. From the way it broke I think it needed to be replaced anyway. It kinda shattered. Does anyone know what the original wood used on this was?

It seems that the consensus wood for this repair would be black locust or maybe bald cypress. I live in Florida. Hot sun.

I have not done fiberglass since I was a kid helping my father with his boat when he tried to improve the strength and water resistance of an old wood boat by coating it with fiberglass from keel to waterline. But I have looked at videos, I think I can do it. I will just take my time and match the curve with a template.


I would post images but I can't figure out how. Never mind, finally got it. Boy, that was four times as hard as I thought it should be.

If anyone knows what the original wood was or has any ideas regarding what to use for an unpainted bowsprit, please let me know. Thanks in advance.

Well, when you do a project boat, you start with a boat that barely works, then you disable it, then you re-enable it. The disabling was sudden. More severe than I expected. What is left of the trailer is junk, except for axle and springs, which were newer. So I need a trailer in South Florida.

I have AAA Premiere coverage with long tow and RV. So I called them, told them I had a 23 foot boat in the woods next to I-75, mile marker 205. They dealt with getting me a 30 foot flatbed, which took 8 hours. They got a 25 foot flatbed out there in 90 minutes (at 1 am on Saturday morning) and he decided, after putting the boat on the side of the road, out of the woods, that he could not have that much overhang. Bow railing, bowsprit, motor stand are not in length. They finally got a bigger flatbed out there at 9 AM.

The tow to my house cost AAA about a grand. AAA dealt with all aspects of finding an out of network contractor that they could hire. I will keep my AAA coverage for trailer tows, first class all the way.
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Old 10-04-2016, 18:05   #81
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Re: What wood for a bowsprit?

FYI Alaska Yellow Cedar is not even Cedar. It is actually Cypress as is Port Orford. Interestingly all Cypress is good for boat building as Cypress is fairly rot proof.

I'm not advocating anything really just spreading what limited knowledge I have. A great construct is to glue together Teak and Alaskan Yellow Cedar together (you can use 80% AYC and 20% Teak) It will yield a rot proof timber of low weight and high strength. If you use clear sealant it will also look amazing.

The nice thing about doing a glue lam is it is cheaper as the smaller dimension wood is less expensive and by alternating an expensive denser wood with a lighter wood is you get good strength with a lot less weight and expense.

Not that hard to do at all.
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Old 11-04-2016, 06:46   #82
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Re: What wood for a bowsprit?

Hmmm. I actually have a biscuit joiner and have made some glueups before. What I have seen, and really don't know how to control, is warpage. I made some covers for an RV sink. I noticed when I made the first one that I got some amazing warping when it got wet. I made another one and buried 3/8 inch threaded steel rods in it, plugged the ends to hide them, nuts and washers to compress the wood. It looked good, I have to look carefully to tell it from the one without internal bracing. It warped in just the same way.

I thought I had reversed the grain on every other piece with the second one but it didn't seem to matter.

I could have just used a plank, cut and sanded to fit as the cover but I wanted the look of a glue up, contrasting grains, stripes of grain patterns....and I was hoping for casual use as cutting boards. Well, the results looked good as long as the boards were dry.

I have visions of the bowsprit curling and readjusting the jib when a wave hits it. But this would be a long thin piece rather than a broad flat one.

Perhaps there are instructions out there. Thanks, interesting suggestion.

The shape of the current bowsprit was a long taper. I could probably make a bald cedar piece that had the taper but was under dimension, then I could glue 3/8" teak to the sides.

This is a very interesting idea. Anaphylactic resin glue, I guess.
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Old 11-04-2016, 14:01   #83
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Re: What wood for a bowsprit?

Use a "woodie"???

... I'm leaving now....
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Old 12-04-2016, 15:40   #84
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Re: What wood for a bowsprit?

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Originally Posted by Brasshopper View Post
Hmmm. I actually have a biscuit joiner and have made some glueups before. What I have seen, and really don't know how to control, is warpage. I made some covers for an RV sink. I noticed when I made the first one that I got some amazing warping when it got wet. I made another one and buried 3/8 inch threaded steel rods in it, plugged the ends to hide them, nuts and washers to compress the wood. It looked good, I have to look carefully to tell it from the one without internal bracing. It warped in just the same way.

I thought I had reversed the grain on every other piece with the second one but it didn't seem to matter.

I could have just used a plank, cut and sanded to fit as the cover but I wanted the look of a glue up, contrasting grains, stripes of grain patterns....and I was hoping for casual use as cutting boards. Well, the results looked good as long as the boards were dry.

I have visions of the bowsprit curling and readjusting the jib when a wave hits it. But this would be a long thin piece rather than a broad flat one.

Perhaps there are instructions out there. Thanks, interesting suggestion.

The shape of the current bowsprit was a long taper. I could probably make a bald cedar piece that had the taper but was under dimension, then I could glue 3/8" teak to the sides.

This is a very interesting idea. Anaphylactic resin glue, I guess.
That's an interesting idea----metal rod in wood glue-up?

I'm thinking perhaps a 1" x 1" Aluminum rod inside a glue-up of Cypress with just a little Teak for beauty and contrast. Would be light and strong as hell.

To avoid warp don't do a parallel lamination but rather quarters so a cross section.

So if you glued up 1 x 1 you'd end up with a 3 x 3 post if that makes sense.

Resaw your wood and then flip so forces are opposing. You can just use dowels for a jig and glue using waterproof submersible glue.

I like the idea of a metal core kinda cool.
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