: How do you avoid the discoloration of the seams?
: Bill

Bill,

I have heard of people putting glass tape only on the inside of the panels, making sure not to get any epoxy on the outside. Use a high quality masking tape to keep the epoxy off the outside of the panels. You have to be more careful with the panels, but the end result is no discoloration. If you want more security while under construction, put a layer of 4" tape over top of the narrower tape on the inside.

A guy here in town did spline joints on his two Coho's, VERY SLICK! He has been discussing this method with Pygmy. They could do this at their shop and everyone would be capable of perfect joints.

Another method is backing plates, I did this on the plywood Walrus. It was plywood on frame so I did it after the panels were attatched to the frame. The panels on my Arctic Tern did not have to bend that much, so it would have been possible to use backing plates without causing flat spots.

There are two reasons that I have heard for discoloration, UV exposure and blush. To stop the UV exposure problems, don't epose the taped seam to UV rays until after the hull is fully fiberglassed and epoxied. To stop the blush problems, carefully wash the epoxied area before sealing and glassing the hull.

I think the best thing to do is avoid glass tape and epoxy on the outside of the hull, until you do the entire hull.

For what it is worth, the same discoloration could appear on a scarf joint if you are sloppy while making it.

The photos below show the discoloration that I had. It doesn't look that bad in most light. Even when I point it out to some people, they can't see it, but it sure does show up in these photos.

Mike