Monday, October 8, 2012

Fabricating Cockpit Locker Lids

Why do I always seem to pick the most time consuming projects. In hind sight, would it not have been better to leave the cockpit alone, live with the shortcomings, mount my propane tanks on the pushpit, and same myself the time and expense. Of course it would, but I am not smart enough to leave well enough alone. I have to try and fix those little things that bug me.

The helm seat was uncomfortable. The propane bottles hanging off of the stern break down faster, and I have enough stuff back there without trying to fit more. Plus I like the idea of having those tanks in lockers. And that is why I cut out the rear deck of the cockpit, raised the seat 5" or so, and put in dedicated propane lockers.

Of course that meant I had to make lids for the new lockers. I have worked with fiberglass before, and on this boat, but I had never created fiberglass items using a mold. Thanks to all the people on YouTube who showed me how to do it.
 Firstly I measured the cockpit locker top and determined how big I needed the locker lids. Then I built the molds above out of melamine coated MDF. For the curved section of the center hatch I just used a cheap piece of mahogany underlay plywood. Then I used a bondo fillet in the corners to round them out. The can of mold magic, (carnauba wax) said to put 4-5 coats of wax on the mold, the internet said to put 8-10. I put 10, and maybe should have put more, however the molds did come off without too much fuss. Put the wax on, wait 20 mins, polish the dried wax. Do that 10 times, ughhh. And for some reason I didn't take a picture of the gelcoat. I ended up putting 3 coats of gelcoat on with a brush. It took a long time to set up, so it was about 2 days just to get that done. It wasn't too hard to get the colors right. I had my local Home Hardware figure out which colors of dye I needed to use to get the color I wanted, and then I just experimented with the quantities. Is it perfect, no way, but it isn't too bad.
 So then last night after dinner I laid the fiberglass. I had cut all the fabric to fit prior to starting. 2 layers of 8 oz cloth and 2 layers of really heavy woven mat that is sewn together, for every surface. I wasn't sure if it would be enough, but figured I could always add to it later if absolutely necessary. I mixed about 10 batches of polyester resin, using up almost a full gallon before I got it all done. I didn't give the glass any time to setup before I was into the next layer. Also, as you can tell in the picture, I added a piece of 1/4" plywood to the center portion to stiffen the top a little, and create a little groove around the outside where the lip of the locker will sit. Hopefully it will provide a better fit.
And here is one of the lids broken out of the mold. It turned out pretty good. I'll give the whole thing a lite sanding with 600 grit wet dry sand paper, but there are a couple of touch-ups to do on the corners first. I used automotive bondo to fillet the corners. In hind sight I probably should have used modeling clay. The bondo didn't come off as cleanly as I would like, or the wax wasn't as effective in the corners. Not that it matters now though. The blemishes are so small that it makes little difference.
In a rush to find out how it worked out, I broke the lid out of the mold before trimming it. I won't do that with the next two. I'll trim them first, using the mold as a guide. In fact I may put the mold for this one back together for that purpose.

Of course the real test will be when I install them. Cross fingers, knock on wood, pray to God of choice......

1 comment:

  1. Hi, enjoying the blog, just wanted to make mention of the necessity of having self draining propane lockers routed to the outside. Propane is heavier than air, so a leak in a tank within a boat hull can accumulate propane in the bilge with disastrous results. Should a bilge pump kick on with propane present, kaboom! So please be sure to vent the lockers to the outside through the bottom somehow, fair winds!

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