Jim: Hi!
We replaced the bowsprit on Zygote almost one year
ago, because of rot and delamination. I don’t have
Rod’s woodworking skills or tools and I was not in my
home port when I needed to do the repair. So a new
sprit, made of teak, cost me about US$1,000.
I agree with Rod’s prescription: you either build a
new bowsprit or splice a piece of new timber into your
sprit. From personal experience, reglueing a
delaminated glue line seldom results in a long-lived
join.
Just as important as the prescription is determining
the aetiology of the condition. Douglas fir glued with
resorcinol, epoxy, or a foaming glue such as Gorilla
Glue, does not delaminate spontaneously.
Weathering factors, such as rain and temperature
changes (eg the mechanical stress of daily expansion
and contraction from tropical insolation) are usually
to blame.
In our case, the linear polyurethane coating we had
had applied to the bowsprit failed, most likely
because of inadequate preparation when the LPU was
applied. That allowed rain water into the wood,
leading to rot and mechanical stress as the timber was
repeatedly dried and wet, heated and cooled.
So our total remedy included applying multiple coats
of clear varnish (so any water ingress can be detected
immediately). We also bought a cover for the bowsprit,
made of Sunbrella by Bob & Dolly Baltierra (Power
Steering and Marine Specialities, 639 Terminal Way,
Unit #19, Costa Mesa, California, Tel: 1 949 548 6978,
Fax 1 949 548 0639).
We now keep the bowsprit covered as much as possible.
Many glues, including epoxy, have a ‘deflection’
temperature that is easily reached when exposed to
tropical sunshine.
Cheers
Bil
BCC28 #116