I'm writing this blog as a journal of my build of a Duo-660 catamaran. Most of the content will be dedicated to this endeavor. I try to populate posts with pictures since it is instructive. The notes tab is for misfit posts. Always nice to have a place for the misfits.

-Esteban

Tuesday, October 27, 2015

Finding Interesting Ways to Screw Things Up

I knew something was up when I let go of the clamps and the rudder still creaked.  The symptom of the problem was that no matter how hard I cranked down on the wedges I couldn't close the rudder at the spar. It was closing at the trailing edge before it was touching at the spar.  So I took this picture, took a break and thought about my options.


I was thinking looking at this that I poured the leading edge epoxy goop to high, and thus too wide. Being ever the optimist I thought that maybe it would just be a different shape than the other rudder and gave a couple moments thought to the sailing implications of having two rudders of differing sections. Thankfully I didn't spent too long on that, and decided to pull it off the jig before investing carbon fiber into it. The creaking sound I heard was the sound 4mm Okume marine plywood makes when it cracks. 


Doing a post-mortem on this, the proximate cause is obvious (too much epoxy goop bead), but the real culprit is overconfidence and haste. When I poured the bead in the rudder I only had a bit of time and did things quickly since I figured I had this down. 

So after two rudder attempts I'm 1 for 2. Here are the two things I will do differently and why:
1. Mark epoxy goop fill line on rudders with red marker or something significantly more visible than a pencil line. Its too easy to lose sight of the pencil line and start guessing at where it was.

2. Change order of operations: epoxy rudder faces with goop in jig first, then epoxy spar onto one side.  With the spar pre-installed it is just in the way just enough to be a pain when putting the goop (contributes to losing sight of the fill line). 

We have company in from out of town for Halloween, did I mention this holiday is a big deal, so now it really will be a week until I'm back at work on my boat.

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