Glassing rudder... advice sought!

[NickHarley]

I've got a solid wood rudder that was encapsulated in glass/epoxy... the sheathing had cracked & delaminated after 10 years letting in water, so I've stripped it back to bare wood. Condition seems OK now dried out & surface cleaned up. See attached for 'before' pic.

I think I'm going to encapsulate it again... something along lines of :-
1. Seal with a really thin coat of epoxy to soak into wood & bind
2. Next epoxy layer (after scrub with acetone?) with a thinish glass cloth (c. 150g/m) so that its still transparent (I like the 'varnished wood' look).
3. Primer/antifoul below waterline & varnish top half to protect against UV. (several layers).

Obviously I'm happy to be told in general terms if there are problems with this plan, but I have two specific questions -
1) How should I physically lay the cloth... by that I mean can I lay rudder on its side & do one side at a time (with overlap on leading edge?), or should I try pointing leading edge up and lay one piece of cloth over both sides at once. I've seen people hang them from ceilings etc on google... but not convinced its feasible on one this size (almost 6 foot).
2) Should I add extra (heavier) cloth below waterline for strength/impact resistance etc.?

Any advice would be appreciated! Many thanks.

 

[DownWest]

Sounds fine. I would add some rovings (or extra cloth) on the bottom curve for abrasion. And another layer below the water line. Wood effect is nice, but under the antifoul? As for laminating, hang it from the pintles, leading edge up, as the fold over the top is easier with gravity.
Personal choice. Resoltech resins. Two coats of the Re1010 onto the bare wood. Then the cloth with Re1020.
Two coats or more of varnish to keep the UV of the stock ( white paint does a better job...)
DW

 

[NickHarley]

DW. Thanks for the advice. Was tempted by white paint... but SWMBO likes wood look (not an 'effect', just transparent), so that decides it!
I've taken pintles off.. thought main point was to seal all wood against possible water ingress, rather than leave 'gaps' around hardware. I could maybe string it up using pintle bolt holes though.
Thanks again.

 

[William_H]

Fibreglassing rudder

I would suggest you plane down the wood of the rudder so that you can apply added layers of fibre glass. The thin layer you speak of will delaminate quickly whereas thicker fibre glass will have strength of its own.
The area just below the bottom pintle is the area most in need of strength. There is a large sideways load on a rudder and a deep one like yours may snap off and the place it will do it is just below the bottom pintle.
Use epoxy because it will stick to the wood better but it will be damaged by UV. I am not convinced that varnish would protect the epoxy from UV certainly not if the varnish fails after time. So paint would be far better.
As suggested I would mount the rudder leading edge upward so that you can use gravity to give a nice conforming layer around the leading edge. Lay the glass over the sides and extend it to past the trailing edge then clamp the glass from each side together beyond the trailing edge but as close as possible. Paper clips would work well. When resin is nearly hard trim the glass at the trailing edge if there is any air gap fill this with resin. You might like to take the opportunity to advance the leading edge perhaps with foam to give more balance to the rudder. If that would be a good idea. If it is like mine and it appears so from the photo you could advance the leading edge by 30mm or more in the area below the hull. Makes helm much lighter.

Just recalling the rudder on my boat is similar shaped but swings between cheeks. One night race helm went funny and I looked over to see what looked like the rudder broken off and horizontal. In fact it was the entire side of the f/g on wooden rudder delaminated and peeled off but still attached at the top. it apparently started from a crack down the leading edge. I relaminated it apparently well because that was 25 years ago. olewill
good luck olewill

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