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Old 09-21-2010
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The Ty37 bowsprit is easy to rebuild as a DIY project. The strakes are alternating teak and 'an unknown asian softwood'. The rot is usually only in the 'softwood' and once disassembled and cross-bolts removed the bowsprit laminations will easily come apart with a few blows with a mallet (and chisel) to break loose the poor polyester 'glue'.
Then all you have to do is clean up the teak boards, get new mahogany, etc. boards, epoxy the whole thing back together, and use a draw-knife etc., to reshape using the OEM teak boards as the 'template' / guide.

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Ty37 bowsprit eventually rots because the through bolting holes for the forestay, the club foot pedestal, the 'hold down bolt' and the cross bolt through the samson posts are never sealed .... and they 'work' under varying sail/rigging loads. To prevent water intrusion in future: suggestion is made to install thin-walled stainless steel 'ferrules' set with epoxy into the OD of the bore holes, etc. to protect the sprit from 'sawing' of the thoughbolts. That 'hold down bolt" through to the stem is virtually worthless and prevents the bowsprit from vertical movement on the 'thin end' and causes the sprit to flex (lamination separations); better to replace with a "gammon iron" as is found on the Baba/Tashiba boats which allows the sprit to freely move up and down as needed. The laminations will crack and open as the sail loading changes due to sprit flex; so, suggest you set additional thoughbolts crosswise/horizontal into the sprit along the top and bottom margins to strengthen the laminations .... if you choose to keep that 'hold down bolt'.

BTW the holddown bolt is only fastened to the underside of the deck and if you break a bobstay under load that through bolt will easily come 'though' the decking. The gammon iron relieves/solves all the flexure (and cracking of the laminations) problems and will keep the bowsprit in place if you lose/break a bobstay.
To also lessen the flexure of the sprit (to lessen laminate cracking) be sure to set the bobstay wire tension to the exact backstay wire tension.

Consider only a laminated replacement. Many replace with solid teak which is subject to large 'ckecks' and splits.

The absolute best replacement would be the "U" shaped tubular stainless steel sprit that Bob Perry designed for the Pacific Seacraft 38.5 (never built) .... leaves the entire foredeck free and 'open'. lemme know if you want a line drawing of this design alternative.

hope this helps.
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