Cure Time for Butt Joints

[taw1126]

A god-awful travel schedule and working for a living are conspiring to keep me without a boat, but I am determined to get the sides butted together this weekend.

I'm using the method shown on JEM's website (wood flour mix to get the long pieces together, then fiberglass) but I don't know howw long I need to let the wood flour cure before sanding & putting the 'glass on. I'm using MAS epoxy, slow cure...any thoughts? I need to use today & tomorrow to get this step done or else it will be several more weeks before I can get back at it.

Thanks in advance.

 

[taw1126]

Follow-up: I just saw Chuck's method and it looks like I could skip the wood flour step, saving some sanding (and restaining) time.

So here's a related question: can I epoxy-saturate both sides (top & bottom of each board) at the same time as long as everything dries on plastic? I cut a garbage bag in half and was planning to use that to keep everything off the floor.

 

[oldsparkey]

You could saturate them and probably get away with it at the same time , I do one side at a time and then go back and glass them together.

The only problem I can foresee is if you do both sides at one time on the saturation the side laying on the plastic might end up with ridges on it if the plastic is not absolutely flat.

If you are talking about glassing the joints on both sides at one time the problem that might make you cuss is the boards moving and being off center since they would be on a slippery surface (wet epoxy).

I don't use the wood flour in the epoxy for doing the butt joints (as you know) it creates extra work where just using the epoxy and a piece of fiberglass works quite well. After all it is the same thing you will do to the boat when you glass it ..... Only epoxy and fiberglass.

Chuck.

 

[hairymick]

Gday Taw,

I use the wood flour mix between the joints simply because that is what Matt reccommends. Onces I apply the mix to the joint, I scrape it off flat while the resin is still wet and then lay the fibre-flass matt right on tope of that and wet it out.

I then leave it overnight, to cure up and do the other side the following day.

If you have two identical panels. I tape the first to the floor in position, do as described above, then lay the next panel directly on top of that one with a sheet of plastic covering the recently done jount and repeat the process. - works OK for me.

Only thing, be careful there are no ridges of plastic rising up in the butt joint where the wood flour is to go.