Monday, May 6, 2013


We did it, the keel is poured!!  No burns, no crying, really almost no problems at all!

We did a lot of things differently this time, and they payed off. 

Here is the setup, our friend John graciously let us commence this circus in his driveway.  We used two tubs this time, mostly because it is horrifying to have 4000lbs of lead in one tub.  I welded stands for the tubs to sit on and then we built a platform to get the fire closer to the tubs.  You can see we also used bricks that John had laying around to block some of the wind.  

Drains for keel mold

I welded the pipes to the tubs just as they are in this photo.  The pipes worked kind of like a snorkel.  They came out the drain of the tub, then to the side about a foot and then up until they were well above the molten lead line.

The pipes are threaded together, so when it is time to pour you simply turn the pipe, lowering it down below the molten lead line, making the the lead flow out.

Look for the steel pipe floating in the lead when the camera goes around the tub.

There were a couple of minor problems.  The first was realized early on.  I knew from previous experience that welding to cast iron is difficult.  It just doesn't behave like normal steel.  If you don't really pre-heat it, your welds just don't penetrate and you end up with something more like metal glue instead of a weld.  Anyway I didn't have anything to pre-heat with so I just welded the crap out of it and thought it would be fine.  
As soon as the lead started to become molten it started leaking out of what looked like hairline cracks in the drain.  I thought that molten lead would be too viscous to flow out the crack but it wasn't and we ended up moving the fire away form the drain to allow that section to cool and form a plug.  I now know that if you are going to pour lead, water test your setup for leaks.

Here was another minor problem, the lead was coming out too fast and starting to erode the side of our sand mold, so I blocked with some wood.


This thing is pretty awesome, apparently there was a very slow leak in the bottom of the mold, but it looks like it plugged itself off. 

After letting the keel cool overnight we returned to clear out the wreckage.   You can see how well the sand works, this is after prying off the sides of the wood box.

It took us few hours but we got the keel winched onto Johns trailer and drove it down to the shop where we rented a forklift to lift it off and into the shop, and there it is just sitting on pipes ready to be cleaned and faired.

We are so lucky to have the support of so many people.  Afton and Dylan, the original team came back for a second try and were so much help. We can't thank John and Lindsey Little enough.  Not having to drive out to the desert was huge, not to mention all the other ways they made this event possible.   The video is courtesy again of PJ and Sarah who showed up just in time to see the whole thing go down.

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