Using Starboard for new bowsprit?

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Bruce Dart
Posts: 25
Joined: Feb 7th, '05, 14:01
Location: Former owner of CD25 Wings O' Morning. Looking for a CD30

Using Starboard for new bowsprit?

Post by Bruce Dart »

I've seen a couple of CD30s recently where Starboard (West Marine calls it 'Marine Lumber') was used in place of teak for a new bowsprit. Although I love the look of teak (until I have to refinish it, anyway) I thought the bright white material didn't look bad. My concern, though, is its strength. Anyone with any thoughts on how it would stand up to side and compression loads?
Fair Winds.

Bruce Dart
John Stone
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Re: Using Starboard for new bowsprit?

Post by John Stone »

Starboard would not be a good choice. The compression loads on a bow sprit are significant. Starboard is also susceptible to UV degradation over time. Starboard is plastic no matter what West Marine calls it. Teak is good as it is very rot resistant and strong (though it is heavy). While it is expensive you don’t need that much. You are probably look at about 6-7 BF I am guessing. It runs about $25.00 a BF depending on where you buy it. But there are other woods you can use as long as you varnish it and keep it varnished. you could also have one made out of SS tubing (expensive) though it does look different than the plank style and there will be other expenses as most of your CD rollers and kranze iron won’t work well with the SS configuration.
jepomer
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Joined: Oct 24th, '09, 08:23
Location: Cape Dory 25 Lyndeborough NH CPDE0622M78E

Re: Using Starboard for new bowsprit?

Post by jepomer »

No. Starboard is not appropriate for a bowsprit. It would snap very quickly under load.

Physical Characteristics of "Starboard"
(http://www.kingplastic.com/products/all ... starboard/)

Properties Units ASTM Nominal Values
Density g/cc D1505 .96
Tensile Strength @ Yield psi D638 >4100
Tensile Modulus psi D638 225,000
Elongation @ Break % D638 >699
Elongation @ Yield % D638 9.8
Flexural Modulus psi D790 185,000
Flexural Stress @ 5% Strain psi D790 3,810
Compressive Properties 10% Strain psi D695 4,950
Durometer Shore D D2240 68
Tensile Impact ft.lbs./in.2 D1822 115
Izod Impact Resistance ft.lbs./in.2 D256 1.1
Brittleness Temp. ºF D746 <-105º
Vicat Softening ºF D1525 253º
Heat Deflection Temp. 66 psi ºF D648 167º
Screw and Nail Withdrawl lbs D1761 657 & 63
Slip Resistance (wet) - D2047

King StarBoard® is the original marine-grade polymer and the industry standard. It is the product of a proprietary process called K-Stran®, the most advanced manufacturing process available for producing consistently flat continuous sheets. King StarBoard® is environmentally stabilized to withstand the harshest marine conditions. It will not rot or discolor like teak and other solid woods, and it will not delaminate like wood laminates. King StarBoard® is easy to work with using standard woodworking tools, and design changes are a snap. In addition, the installed cost of King StarBoard® is less than teak, other common marine woods, and fiberglass. Plus, our large sheet sizes maximize your yield. Boat buyers appreciate King StarBoard’s® low-maintenance finish. Repair and refinishing due to weathering and decay are eliminated, and cleaning is easy. King StarBoard® has a handsome matte finish on both sides to hide scuffs and scratches that would show on glossy textured sheets or acrylics.

King StarBoard® is upgradable with our exclusive antimicrobial additive King MicroShield®. The latest technology for protecting the product surface against a broad spectrum of damaging bacteria, algae, and fungi by reducing the amount of microbes by 99.99% and killing the microbes on contact. See our King MicroShield® page for more information.

Popular Applications:
Hatches, Doors, Grab Rails & Handles, Step and Dock Boxes, Rod & Cup Holders, Countertops, Chairs, Tray Tables, Frames and Trim.

General Applications
Made of the finest polymers available, using our
proprietary K-Stran process for superior flatness and consistency.
Environmentally stabilized for harsh sun and tough marine environments.
Will not rot, swell, splinter or delaminate when exposed to humidity or water.
Precise tolerances ensure consistent color, thickness and density, even for special thickness gauges and custom
order colors.
Easy to fabricate with standard woodworking tools and requires little or no finishing.
Available in eight standard colors to match or accent any gelcoat.
Unlimited custom/proprietary colors.
Durable matte-textured surface on both sides.
Easy to clean and never needs refinishing.
Edges finish cleanly and easily.
Forms easily for smooth curves.
Has passed the Federal Motor Vehicle Standard 302 fire test required for use in motor vehicles, including
motor homes.
Available in large sheets up to 54” x 96” or 48” x 96”.
Custom sheet sizes available.
Shipped with a protective masking on one side.
Proven on thousands of boats and yachts.
Experienced boat builders and boaters know the King StarBoard® brand and trust it more than any other.
John
CD25 #622
CPDE0622M78E

"You are not going to find the ideal boat. You are not even going to have it if you design it from scratch."
~ Carl Lane
Klem
Posts: 404
Joined: Oct 4th, '09, 16:51
Location: CD 30k (for sale), CS36t Gloucester, MA

Re: Using Starboard for new bowsprit?

Post by Klem »

I believe that many CD's came with Oak bowsprits as well as teak ones. The bowsprit that I replaced on my boat a few years ago was most definitely white oak and it really looked original to me. I replaced it with white oak, just a little bit thicker and I expect it to go another 30+ years.
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tartansailor
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Location: CD25, Renaissance, Milton, DE

Re: Using Starboard for new bowsprit?

Post by tartansailor »

Starboard is high density polyethylene, the same stuff used to mold milk jugs.
Under load it will deform!

Dick
Viam Inveniam Aut Faciam
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marka
Posts: 218
Joined: Feb 5th, '05, 19:50
Location: Linda Jean
CD 27
Hull 219
Oswego, NY

Re: Using Starboard for new bowsprit?

Post by marka »

At the risk of being repetative (and therefore predictable), i'm an advocate for using white oak to replace any teak that needs to be replaced.

It's readily available in long lengths, about 20-25% of the cost of teak, glues better, hold screws much better and finishes beautifully. While not quite as rot resistant, it'll last plenty long under all conditions.
Mark Abramski
sharkbait
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Joined: Oct 22nd, '08, 09:46
Location: Typhoon Weekender

Re: Using Starboard for new bowsprit?

Post by sharkbait »

You might consider cypress heartwood.

Cypress is a popular choice for building construction, posts, beams, decks, docking, porch flooring, greenhouses, siding and stadium seats." Cypress is also used to make caskets, doors, blinds, sash and other types of millwork. Fine grain cypress is used to make custom cabinetry.

Because of its watertight durability, it is also used for cooperage, shingles, in tanks, vats, ship and boat building and to make railroad cars. The heartwood of cypress contains a natural preservative oil which makes it one of the most durable woods for use in exterior applications.
Have A Nice Day
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tartansailor
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Joined: Aug 30th, '05, 13:55
Location: CD25, Renaissance, Milton, DE

Re: Using Starboard for new bowsprit?

Post by tartansailor »

I'll second cypress heartwood, especially for rot resistance.
Viam Inveniam Aut Faciam
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