Ignoramus28874 wrote:

On 2010-08-16, Pete C. wrote:

"Pete C." wrote:

Ignoramus28874 wrote:

On 2010-08-16, David Billington wrote:
Ignoramus28874 wrote:
This is actually a practical application, as someone said he may want
me to do a parts run for him.

Let's say that out of a flat stock, I want to cut out a part and it
needs to be beveled on all sides.

I obviously cannot do it in one "start and forget" application, as at
some point the part would need to be clamped from top or something, to
avoid burs or unmachined edges.

Someone must have already invented a good scheme for doing so, any
ideas?

i

Maybe have a look here http://www.miteebite.com/ at some of the T slot
products . Can't give a direct URL as the site doesn't do that
annoyingly. Maybe the Advant-edge clamp system.

Now that I thought some more about it, it is not as difficult. All I
need it to stop the program, and use a Vise-Grip to clamp the part
down to the backing, and then continue to cut it off.

i

Vice-Grips are not intended as machining clamps. Try the clamp bars in
the holdown kit, they are intended for the use and will give you high
clamping pressures when used properly.

BTW, have you been reading the Machining Fundamentals book? It explains
various work holding scenarios including the clamp bars.

I have been reading it, but not about clamps.

It's in there, perhaps not in as much detail as the actual cutting
operations. Chapter 18 shows clamps in use, fig 18-38, 18-49, 18-50,
and 18-61 all show clamp bars in use. The tapered end of the bar rests
on the part, the serrated back end of the clamp bar rests on the
serrated slope of a step block half to support the end of the bar so it
is level with the work, and a stud is used close to the part to pull the
clamp bar down and hold the part. If you have the workholding kit and
play with the parts it will make sense.