I have made a couple different sizes of brakes for my 20 ton HF press.
The basic concept is to machine an appropriate vee block for the bottom
and use square bar at 45° for the upper die. You can see what I did at:

http://www.spaco.org/Press.htm

I have bent 90° angles in 5/32" or so thick mild steel, 15 or so inches
wide with the largest brake by bending some, sliding and bending some more.
There's plenty of power left over.

I made my dies from mild steel and they okay for occassional use, but I
do nick them with small parts from time to time when I squeeze real
hard. So, if I had the choice, I'd use 4140 or something like that
next time. I don't think they need to be real hard.

In the third picture down, you can see my biggest brake. In the center
of the vee block, you can just make out the scrapes that I put in it
bending some short, narrow pieces of 1/8" material 2 inches wide, that I
do on a semi-regular basis.

I use the HF air-over hydraulic jack in this machine, and I love it!

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

Ignoramus24341 wrote:

I wanted to make a homemade brake for bending small sheet metal
things. (I have a press). I think that the concept is straightforward,
however, I would like to know if there is any sort of a table that
tabulated bending effort per inch of the width of metal being bent,
depending on thickness.

Also, for the dies, would it be more proper to use high speed steel as
opposed to mild steel (for strength).

Thanks

i