I remember reading about the material that the 9 x 3 x 3/4 in piece (attached pic, but not sure where it went to) that slides into the aft end of the bowsprit is made of. I did a lot of searches, but did not find any references to it.
Anyway, besides not knowing what to call this item, I don’t know what it is made of. It appears to be a sandwich of two pieces of a ceramic-like material that was wrapped with some other material to make it more durable to the elements. My piece fell victim to UV or other degradation, and the coating is well “worn off.” Where the inner material is exposed to the elements, it seemed to have a significantly chalky, as if oxidized. When scrubbed clean, the chalky coating is gone, and there is significant erosion of the inner material.
Two questions for the community:
What is this material, and where would I find it to replace the piece on Finesse?
If unavailable, what is a substitute material? This part carries sheer loading, so something like acetal (Delrin) might be a reasonable choice. Sun exposure is a problem for plastics, though.
Thanks for your ideas and inputs. If anyone knows what the outside coating is, I might be able to recoat this piece where the sun hits it. The coating is intact where the wood covers it.
If it helps, Tom, I can tell you that the bowsprit fid for the Bristol Channel Cutter, as made by Sam L Morse Co in the 1990s and 2000s, was a piece of Delrin.
In the case of BCC Zygote, I noticed deterioration of the upper surface of the Delrin fid after three in the tropics. I replaced Zygote’s fid with one made of timber. Zygote and I were in Malaysia at the time, so I chose one of the tropical hardwoods.
Luke and Bil … thanks for your suggestions. I think that your ideas of a good piece of hardwood is a very good one. I think that I will “follow suit” and replace that fid (thanks also for expanding my vocabulary) with a good piece of hardwood. I’ve been looking into Ipe for a deck replacement, and that wood is probably a good choice for weather resistance. Going with a plastic replacement would just ask for more UV degradation.
There is nothing wrong with Delrin. And it is not subject to rot.
Delrin is plenty strong enough for the job. It’s just that the surface of standard white Delrin becomes chalky and erodes after exposure to UV.
Du Pont des Nemours, the manufacturer of Delrin, now has a variety of Delrin that can sustain at least 20 years of exposure to UV. It’s black in colour because the Delrin is filled with carbon-black. The designation is Delrin 507 BK601.
I think the 507 is the temperature at which it is formed. The BK refers to the carbon black.
If you are changing to a hardwood, look for a timber with a high compressive strength parallel to the grain. And then get a piece oriented so the grain runs parallel to your bowsprit (most timber is stronger in compression parallel to the grain than perpendicular to the grain).
I replaced Puffin’s fid during the winter of 2016 when I stripped and refinished her bowsprit. The original fid was enamel painted hardwood. I replaced it with a piece of teak and sealed it with a couple coasts of West Systems epoxy (207 UV hardener), sanded and applied three coats of Captain’s varnish. Turned out great and is holding up very well. I suspect that it will last for some time. I also used this same approach when I refinished the bowsprit. Anyway, for what it’s worth…