I have done this with my 20 ton press. I added a 1" diameter air
cylinder to the release valve on the jack and put both control valves on
the floor. My "main" brake is a 10 inch piece of 1 1/2" square stock
mounted at 45 degrees with a mating v block. The V block has
adjustable guides. Speed isn't much of a problem. I can bend 10" of
3/16" plate with no problems and I have bent 20" of 10 ga. in steps as
another guy said. You really don't need a V block for many things.
The first on I made was simply 2 1/4" X 1 bars welded to a piece of 3/4"
plate with a gap between the 2 pieces to form the "V" area.
If you are going to bend a lot of heavy stuff, I would consider
using medium carbon steel or 4140, etc. for the dies. Mine are hot
rolled A36 and they do require dressing from time to time.
There are some pix of my setup: http://www.spaco.org/Press.htm
The focus of these pictures was to show the press setup for welding
damascus knife blanks, but you will get the idea.

Pete Stanaitis
-----------------------------------------------------------

Bob Engelhardt wrote:
I think I'll get the HF 20 ton press:
http://www.harborfreight.com/cpi/cta...emnumber=32879
and their 20 ton air-over jack:
http://www.harborfreight.com/cpi/cta...emnumber=41487
make up some dies and use it as a press brake. It would be used mostly
in place of a finger brake, which I can't afford. Seems like it would
be more flexible also.

Before I do, I'd like to get some input as to its limitations. The ones
I see are that the material can't be more than 22" wide and that the
cycle time might be slow. How slow would it be?

I assume that I could make partial bends (less than the angle of the
die) with a partial stroke. Is this feasible, or will I need a
different die for each angle?

Any estimates as the the maximum guage for a full width bend (22")? How
wide could 1/4" stock be bent?

Any experienced users care to share their thoughts?

Thanks,
Bob