Monday, October 5, 2009

Melt With You

This weekend I had a go on the rudder and keel bulb.

On saturday I planed the shape of rudder from the laminated blank I made many moons ago. The keel was good practice. :) An electric planer is great when used with care. As with the keel I traced the profile on the ends of the blank and used the planer to "step" down the blank until I hit the line of the profile. I then planed those steps down until I had the foil nearly smooth. From there, I used the planer to cut a nice channel to recieve the carbon fiber lay up of stiffness. I saturated the carbon, layed it in the channel, and then smeared Microlight filled over the whole foil. Sanding to come...

I also poured the keel bulb yesterday. I have to note that Kevin and his wife gave Traci and I the best (my opinion!) wedding gift: an aluminum pot, an iron skillet, a ladel, and a bottle of champagne---all lovingly lead-tainted (maybe not the champagne). I must say, it was the only wedding gift which required hand-washing after opening.

I used Kevin's excellent blog post as a guide. The unseasonably cool weather this weekend (50-55F) and the wind made the job tough and Traci wanted NO part of the Great Lead Melting. Can’t blame her. :) So I was working solo. I think the temp and the wind made the lead slow to melt, so ultimately I ended up placing Kevin's aluminum pot directly over the turkey fryer burner, rather than on top of the iron skillet as he did. This worked fine, but by the time I was done the bottom of the aluminum pot had deformed slightly to match the grates on the burner. Careful if your pot is thin walled!

The pour on the first half was only OK. I don’t think I had enough lead in the pot when I started pouring, so layers started solidifying before I got the next layer poured. I have a couple of layers of lead that don’t seem well adhered so I think I will wrap the bulb with a layer of glass tape to keep everything together. It will also be bolted crosswise to the strut, so I am not all that concerned about the integrity of the bulb.

The second half went much better. I consistently kept more lead in the pot which meant much less time to melt additional pieces and therefore less time between ladlefuls of molten sweetness.

Interestingly (but not surprisingly) the second half, which I poured in a much shorter period of time, contracted significantly when it cooled. It ended up being a ¼” lower than the top of the mold and 6lbs. lighter than the other half (80 lbs.). I think I will get the halves bolted together and then try to seal the gap with heat-resistant mica tape and fill the gap with a small scale pour. Should get me up to weight, I think.

1 comment:

Anonymous said...

Really nice blog and your build is looking sweet!!! Are those drink holders in the deck? If so, great idea - can you post some pics of how you built them?