Wednesday, June 4, 2014


I had been worrying about building the new cockpit coamings for a long time. Not because I didn't think I could build them, but because I thought that they might snap when I bent them in place.  My worries went back to a few days after I committed to using Sapele for the new exterior wood instead of Honduras Mahogany.  I found that while Sapele is a good rot resistant tropical hardwood with many of the workability characteristics of Honduras Mahogany and other commonly used wood in marine applications, it is not a good bending wood.  In fact it can be a bit brittle and has been known to split when bent to a significant degree.  It also doesn't soften up with steam or a good water soak.  For that reason, it's rarely used for planking or other applications where the wood has to be bent.

So I was understandably worried, but I think they may have been a bit unfounded.  With all the time I've spent rebuilding the cockpit, you'd think I would measure the radius.  I hadn't. It turns out that the bend needed was only about 3.5".  

So at lunch today I took the raw boards I sanded down in the drum sander last night and laid the old coamings on top of each board and clamped it in place and traced their shape onto the new board.  I removed the old coaming and using a jigsaw I cut the new coamings out, making sure to cut a little bit proud of the line. I managed to get both cut on my lunch hour and beat the rain so I didn't have to make a mess cutting inside.  I brought them over to the boat and went back to work (my real work).

After work I spent a few hours shaping the boards where they will butt into the cockpit corners.  Most of it involved rounding over the backside corners for the aft end of the cockpit, but the forward section needed to be chiseled out so it sat flush.  This took quite a bit of time because I didn't want to screw anything up so I just took it slow.  My new set of Stanley Sweetheart 750 series chisels made the job actually fun; they are so sharp and precise, even a really hard wood like Sapele just sliced like butter (well, maybe frozen butter).  Along the way I kept fitting them in place to make sure I didn't cut too much.  

Once I had them fit to my liking I had to go to a family commitment at my son's school, but thankfully we made it back home before dark so I grabbed a bottle jack out of my truck and ran over to the shed.  I gathered up a bunch of scrap wood I had laying around in the shed and screwed together a makeshift ram and fit it horizontally across the cockpit.  Then I positioned the bottle jack in the ram and slowly started pumping it up.  I never realized it, but bottle jacks don't really work well horizontally (or maybe it's just this one).  Anyway, it took a bit of fiddling but I managed to get it to work well enough for the few inches that the boards needed to move.  As I pumped it up, I incrementally pushed in a large 2x12 that was just about cockpit width just in case my bottle jack ram contraption popped out of place.  

It all went much smoother than I had hoped and both coamings happily cranked into place with no cracking or fight at all.  Yay!!!!!  I'm really glad I had the old coamings to use as a template or this would have been a much harder job.  There are a lot of strange angles that I wouldn't want to guess at.
I left them in jacked in place for the night so they would hopefully release a little tension spending the night in position (I don't know if this will make any difference, but it can't hurt).  I may get a few bolts in place tomorrow just to hold them in place better and then start fairing the sheer.  After that I want to start building the forward coaming blocks that will ultimately tie the coamings to the sides of the cabin top.


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