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Richard,
Want to speed up your lathe making process?
Try the lost styrofoam technique. You just carve the part you want (allowing for
shrinkage) out of blue foam (yup, same stuff we build Vari-Ezes and the
like out of) or even the white bead foam (not quite as fine a surface finish)
and make a pouring sprue out of foam. You use a little clay flowerpot with
the bottom knocked out for a funnel, just make sure the sprue comes through the
bottom of the pot, or the pot is securely seated on the sprue. You bed the whole
works in a 5 gal bucket of DRY!!! sugar-fine sand. Melt aluminum and
pour.
The foam burns up as the aluminum hits it,
but stays long enough to hold the shape in the sand. Venting is handled by the
sand, so it will NEVER spit back or leave blow holes as long as the sand is DRY.
A completely reducing atmoshpere is created by the burning foam , so the surface
finish is excellent. If you can work the sand in, you don't even need a core, as
you will not have to take the mold apart to get the pattern out of the mold. Ten
or fifteen minutes after pouring, you pull out the part, perfectly
replicated (down to sanding scratches in the foam). I was absolutely astonished
with the ease of it, and the spectacular results, on my first try.
The only drawback is that you get one part
per pattern. Are you making more than one lathe?;-) Gingery's process certainly
teaches a lot about patternmaking, but this is a LOT faster and easier. I have
used it several times with great success. I have also done green sand molding.
This is MUCH less work.
I have a 20gal garbage can Gingery-style
furnace and a crucible made of 6" pipe. It burns about 15lbs of cahrcoal per
run, I can liquefy about 40lbs of aluminum at a whack, and it will melt that
40lbs in about 25 mins......yeah, I do this, too. Nothing like a
four-foot flame standing out the top of the furnace at night;-) I am about
to build a cupola out of two 20gal grease drums so I can start melting iron.
It'll run about a hundred pounds an hour.
BTW, if you are serious about that little
6x18 Craftsman/Atlas lathe, I have two that can be made into one really nice
machine. This includes a steady rest, follow rest, three and four-jaw chucks,
pulleys/belt tensioner (2), change gears, and some other stuff. Let me know if
you want them. I'll make you a GOOD deal. Mike C.
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