going to be making home made pressbrake, jack sizes?

[brendan_h]

think i am going to make it about 400mm long maybe 500mm depending what i got lying around.

just need to know what size tonage jacks should i use? looking to bend anything up to 8mm over the 400-500mm though it probably wouldnt be likely i would need to do this but i would like to have the capabilty there.
just for using around the home making stuff up. i would say mainly 3-5mm steel, aluminium ect
just a side note would a pressbrake be able to bend 1-1.6mm stainless sheet?

and what spacing do the bottom dies need to be?

[aametalmaster]

The rule for the bottom die is 8 times the thickness of the metal you want to bend for the width of the vee...Bob
http://www.accurpress.com/#loadCalculator bottom left side for a calculator.
http://www.americanmachinetools.com/pressure_table.htm

[Diverdude]

Do a little "Reasearch", look on some of the tol web sites for ideas. I know a few have 20 and 40 ton shop presses and the web sites probably have a few dimensions. I built mine using a 20 ton jack. havent built the press brake yet, material still sitting in the corner. Go big on the header over the jack, I have 2 pices of 6" channel on mine and I've had it bow a little when pressing a stuck bearing

[m.k.swelding]

a twenty ton jack I would think would be just right.

[brendan_h]

going by the calculator i think maybe a 30-40t jack would be good though may go for a 20t.

also because of the different thickness i want to bend the bottom dies need to be adjustable? what would i use for dies? i was thinking some 25x25 heavy RHS or maybe even solid?

[aametalmaster]

going by the calculator i think maybe a 30-40t jack would be good though may go for a 20t.

also because of the different thickness i want to bend the bottom dies need to be adjustable? what would i use for dies? i was thinking some 25x25 heavy RHS or maybe even solid?

You could use heavy flatbar with bolts and a thick spacer in between and let the flatbar ears stick up. Or you can use thick angle placed on its point and re enforce the sides with flat...Bob

[aametalmaster]

Sort of like this...Bob