Thursday, February 13, 2014

Bushing rework, Bulkhead 7 modification

I celebrated a little too soon regarding my nicely aligned bushings in the centerboard case.  This last one to be installed had only been curing about 12 hours, so the epoxy was not fully set, and when I dry fit it in the hull and left it overnight it had a chance to sag.  I discovered it the next day when the epoxy was fully cured.

I trial fit the centerboard in the case, and it was not too badly out of alignment, probably would have been serviceable, but I decided to fix  it.

I heated up the bushing and epoxy with my Milwaukee heat gun (very handy tool).  That softened the epoxy up and I was able to push the bushing out of the hole.  When I used the high setting I charred the wood a bit, so I backed off on that.  

I drilled the recess out to 1", which gave me 1/8" around the bushing this time, vs. the 1/16" I had before, and this made it a lot easier to get the epoxy in and poke out the air bubbles with a toothpick.

I still had a couple small bubbles, and a gouged the wood a bit with a chisel.  I'll use a bit of thickened epoxy to fill in those defects.

Bulkhead 7 is the rearmost except for the transom, and it had large lightening holes in it.  The build manual suggests filling those in to form independent watertight compartments in the rear corners of the boat, and after consulting with other builders on the SCAMP forum I decided to go ahead and do that.  Access will be via a hatch on the seat top.

I cut pieces to fill the holes and applied thickened epoxy, then clamped between waxed paper and boards.

Turned out great.  This is right out of the clamps, with no cleanup.

A little scraping and a bit of sanding, and it's ready to coat with epoxy and install.

No comments:

Post a Comment