Jim Wilkins wrote:
"Ecnerwal" wrote in message
...

In article ,
"Bob La Londe" wrote:


It gets into everything. Always have to sweep it up, but today I loved
it.

I decided it was time to pound that dent out of the cover on that motor.
I
wasn't looking for pretty. Just functional. I picked up a 16 oz ball
peen
hammer and walked outside looking for something to put the cover on
before
covering that big dent with a punch of smaller dents in the opposite
direction. I didn't want to distort the shape of the cover too much in
the
process. I threw it on the ground in the sand and worked it over with a
hammer for only a couple minutes, and the dent came right out with no
real
distortion of the cover. The sand gave under the blow of the hammer, but
supported the cover firmly where the hammer wasn't falling.

Now take two heavy pieces of leather, insert sand and sew closed. My
archaic armor making friend used that a lot, set on top of the anvil.
His was perhaps an 8" disc, perhaps an inch thick.


A shallow round depression in the end of a log slice works well too. I
carved the depression with the tip of a chainsaw, walking around the log to
emulate a lathe. If you don't care about preserving the surface finish the
end of a large pipe or the depression in the center of a disk brake rotor is
good enough. The hammer stretches the metal, it doesn't have to press it
against the bottom of the hole unless you need an exact shape.

jsw



I used the large pipe trick but wanted to preserve the surface finish on
some 5mm aluminium so used some 5mm UHMWPE sheet I had around between
the pipe and al. The surface of the PE sheet didn't look to good after
forming but the aluminium hardly showed a mark.