daggerboard finishing

[Nessa]

I have built a dagger board for the Bonito using two sheets of ply glued together with epoxy, then have layered over some cloth sheets - two each side, then given a final coating of epoxy each side. The board itself seems ok, but the edges are very uneven. I figure I shall sand them down to smooth and even, but how should I then coat them/protect them? I could wrap cloth round and coat with epoxy, but would that give enough protection. Ideally I would like an edge built up of epoxy mixed with filler, but how would I do this?

I am after functionality, not looks.

[JimC]

Ideally I would like an edge built up of epoxy mixed with filler, but how would I do this?

I'm not sure you do: pure filler edges can be brittle and or too flexible and [prone to damage. Give this a read, although its for a higher tech foil much is the same. If you are planning a glass coating then one layer of 80 - 100gsm glass would be enough, two if you think your finishing might be a bit brutal. For a strong and repairable trailing edge I think I'd chop the ply about 10mm short of where I want it to end up, then build up a new trailing edge core with glass, sand it to shape and then put the glass sheathing right round it. Toget the new edge close to shape, provided its straight, start with your bench or whatever and cover with parcel tape and, using some chocks at the leading edge, clamp the foil down so that the pacel tape covered bench is parallel with the blade. Get a piece of 3*2 or something and also cover with pacel tape. Now lay up successive layers of glass against your core which is your new trailing edge. Put down enough to be really oversize. chuck on a piece of peel ply and then the 3*2, edge to desired adge of foil and clamp down like crazy. Excess glue and some glass will spill over the edge. When all cured remove and sand down glass trailing edge so its the desired profile. Then add your overal glass sheathing covering completely the strong trailing edge, and finish as per the article.

http://www.sailingsource.com/cherub/bldfoil.htm

[Nessa]

Thanks Jim, I think I can do that, or at least I will have a go. I have to say I am very much enjoying having discovered the cherub site. So much inventiveness, and almost the equivalent of the home built kit boats from days of yore!