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acrylic; motors

Hey, all.

I was going to say "I built a su*b over the weekend," but then I wasn't
able to.

Nothing fancy. I sawed the bottom off a plastic 55-gallon drum which
contained Mountain Dew flavoring, and sawed a little round window in the
side, near the top. The idea is that I'll bolt together a steel frame (from
an old bed) which goes over the top and down the sides, to hold a big heavy
piece of iron some distance below it. Then I'll stand on this "keel" with
my head up in the air pocket, and sink to the bottom in some not-very deep
water, and maybe sort of Flintstone-car around with one foot.

I guess it's more  a diving bell than an actual sub, but I was desperate:
it's been crazy-hot here, but standing in the lake one gets swarmed by very
nasty biting flies. My solution is to stand around on the bottom. (Yes,
I'll remember not to jump out and swim to the surface holding my breath.)

Anyway, the point: the problem I had was wrapping the flimsy acrylic
material I had lying around, to the curved surface of the drum. I went
through 3 pieces. They have a tendency to crack suddenly while they're
under tension from being wrapped, and I do things like drill holes in them.
It seems I remember talk of using heat to curve some window material. Was
it acrylic? How much heat? Can anyone give me a quick hint or two about how
to do this?

[*:-- Does the list software still automatically doo-doo on messages which
contain "sub" in the first few lines?]

Also --
I've seen discussion here of electic motors sealed in oil to keep water
pressure out, but I never paid much attention, because it didn't apply much
to me. But now I'm wondering a couple of basic things: (1) So is oil like
water then -- not very compressible? (2) Does this work with just any
motor? Why doesn't the oil short out bare electrical parts, like brushes or
whatever? Is oil not conductive?


---------
David
buchner@wcta.net
http://customer.wcta.net/buchner
Osage MN USA