I was Chief Engineer of a brewing company in The Fiji Islands in the late
70's.
We always had at least 20 tonnes of CO2 on hand as it is collected from the
fermenters and re-injected later.
We often made dry ice by taking liquid CO2 from the storage tanks and
bleeding it through a fitting that had a number of mesh screens in it. It
came out as snow ( the commercial stuff is pressed into blocks) which we
would put into denatured alcohal. This would cool the alcohal down to about
minus 80 F, if I recall correctly. we used it several times to turn a few
thou off the rubber coated cylinders used in labelling machines. They were
set up on mandrels and replaced in the cold alcohal every few minutes as
they warmed up pretty quick. It wasn't an ideal solution as the finish
wasn't as good as I would have liked, but it kept us running until a new one
could be sent from Melbourne.

We used it a quite few times to shrink shafts so we could get bearings off.
Dip the lot in the cold pot,heat the bearing quickly with an oxy torch, hit
with a big hammer, and Bob's you uncle.

It also made a hell of a bang if you put a bit of it in a plastic Coke
bottle and sealed it up well.



"Wes" wrote in message
news
John wrote:

Freeze it with liquid nitrogen, then drill the holes. You could try just
putting it in the freeze depending on the type of rubber compound. or
just wait a couple of weeks and put it outside.


I'm curious if dry ice would be good enough? Somewhere I saw a design to
make dry ice
using compressed CO2. Wish I could find it now. We have CO2 for welding
that I could
tap.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller