Wednesday, July 28, 2010

Applying the Rails

I managed to get both rails on this week and it wasn't as tough as I thought. The glueing together of the rail pieces that I did last week worked well with no separation issues when I inspected them. One of the rails was slightly out of alignment where the last short piece was glued to the second longer section, but that turned out to be a non-problem when I went to glue it to the hull.

Most of the first day was spent planing the taper of the bow ends of the two inner rails as advised by the instructions and then cleaning up excess epoxy by planing, sanding, etc. I'm a pretty slow planer but I'm getting better. Each inner rail was then dry fitted to the edge of the sheer by means of clamps and then two countersunk holes were drilled into the breast hooks on each side through both rails. The wood used for the rails is extremely hard and I was forced to discover the higher speed setting on my cordless drill. One rail is removed, both contact surfaces are covered with epoxy, the rail is then wrestled into position and the two wood screws are driven through the rail into the bow breast hook side. Then it's simply a matter of applying the rail progressively toward the stern, attaching clamps as you go. When you get to the stern breast hook two more holes are drilled and screws driven home. Then you do the other side. I managed to use every c-clamp, spring and spanner clamp I had, 39 in all! CLC says that 15 is the minimum and 30 is better but 45 would be even better, with most of them being c-clamps.

I can't imagine attempting to do this with just 15 clamps. You're not so much bending the rail to the sheer as pulling the sheer out to meet the rail, and for this reason the much more powerful c-clamps are more useful.

The instruction book says to rasp both stems down to a one inch flat surface, but I just noticed that the photos in the book show the top of the stems are left pointed, which is news to me. In the shot at the left you can see a gap is created between the rails and the prow because I flattened the stem some in this area as well. I'm going to have to modify both points when it comes to planing down the rails to a "pleasing shape" as CLC says, and I have a plan for this.

After letting the inner rails cure for 24 hours minimum the 8 wood screws are removed from the bow and stern. Mercifully, the rails didn't pop off the boat when I did this. I'm getting more and more confident of the holding power of the epoxy. The second, outer set of rails is attached in the same manner as the inner ones. Here the spring clamps are almost useless because you're pulling not only the sheer but also the inner rails out to meet the outer rail. A 48 hour cure time is needed now at 70 degrees. No problem because I have to be back in Minneapolis until sometime next week.

Next week: rounding the top outer edge of the rails and shaping the points. I'm thinking of buying or borrowing a router to save on sanding time.