"Mark Rand" wrote in message
...
On Sun, 9 Dec 2007 09:47:28 -0500, "Ed Huntress"
wrote:


"Robin S." wrote in message
...
On Dec 9, 12:01 am, "Ed Huntress" wrote:

Aha. I was hoping you picked this up. So, what do you think these
restoration guys are doing? Epoxy?

To be honest I don't have any idea. Completing the tryout on a
production draw die takes thousands of man hours. I would be very
interested in seeing how these guys get their dies out at a reasonable
rate. Mind you, manually grinding a steel die is a lot different than
manually shaping an epoxy die. And I'd be fairly surprised if their
panels come out of the dies with zero (or perhaps one or two) cosmetic
defects, not to mention the dimensional defects..

One thing though, once they get the die right, it can be scanned and
reproduced on a mill/router fairly easily (if the original epoxy tool
doesn't survive panel demand).

Sorry Ed.

Hey, don't be sorry. Look at this as an opportunity. d8-)

I'm really curious about it. Making a body-panel die of the right shape,
more or less, that will last through a short run, more or less, has been
done for at least 50 or 60 years, using Kirksite and epoxy. Making
precision
replacement panels, especially ones that can fit together reasonably into
a
complete car, like the ones described in that NYT article, is something
else
again. As you mentioned, getting the springback right, and all the flanges
and so on is not the same thing as whacking out the basic shape.

I'll see what I can find out. Maybe after the holidays.


Could you use an original panel to get most of the bulk in Kirksite and
then
tune the punch from there? PU for the die block.

I don't know. Shrinkage of the Kirksite might be a problem. I forget its
characteristics.


Or even, use that as a pre-form and then wheeling machine from there...

Kirksite has the advantage that once you've done the limited run you can
just
put it back in the crucible...

It's been handy material for a very long time, for short-run and prototype
work.

--
Ed Huntress