Wednesday, May 2, 2018

Stem Lamination part 2 - the fail!

You know they aren't all wins in this boatbuilding game. The stem for this plan needed to be thick and wide, so I thought I would start with some 9/4 white oak and laminate it up. That turned out to be a complete waste of about $30 worth of oak.

Last time we looked, I had just cut the strips. Making the bend is a 2 part approach. I have to soak the oak for a bit to make it flexible enough to bend without breaking. Then after it dries in the clamps I can remove it, glue it and clamp it up again. The glue should be enough. Start with the clamping form


Lofting of the stem pattern

Soon to be a box

Transfered the pattern to a board and attached some 2x4 blocks for clamping

ready to go

Strips just a-soakin
I made a box from some scrap plywood and threw a tarp over it to hold the water, then brought hot water out from the house. I don't have a steam box setup, so this was the best I could do and it's worked before.

One lonely strip

I could only bend 5 at a time

Kid approves
After I had enough strips bent, I put them back in the form with glue to hold up more permanently

Glued up in the clamps - the plastic prevents the stem from sticking to the form


That's a lot of strips



Finally out of the form
Now this is where it all goes horribly wrong. I let the glue dry in the clamps for a few days. I think I left the strips too thick? Or maybe the bend is just too sharp. I wanted to glue the stem in two part, so I could cut the rabbet into the sides of the parts before they come together, it's much easier than using a solid stem.

Starting to separate

That will not hold water

One block falls apart while the other is still in the glue
they keep getting worse

Straightened out and came unglued

Both parts should look about the same
Spoiler alert: the other part didn't hold shape either. You expect some springback from a glueup like this, but this stem became completely useless. So now I've still got a shitload of oak strips if I ever need them. But I have to go back to square one building this stem.

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