Pressures of 10,000psi are not uncommon in hydraulics on small hand powered equipment. So generating a force of even 50tons whilst slow is possible, even easy ! One very useful addition to any hydraulic gear is a pressure gauge tapped into the cylinder feed, this will give you an idea for the applied force and make repeating the task easy. I'm supprised that hydraulics are not mentioned on here more often as the principles are simple and can be put to many applications.

The idea of hiding the return springs in the box section side tubes is neat. Using double acting rams one can avoid the need for the springs and also then use the "press" to pull, though with a slightly lesser force. Then there is the hollow cylinder, very useful. Noel.

If one is going down the route of power operated hydraulics then the following calculations are worth remembering !

Sorry it is imperial units ! 1ImpGallon = 4.55L 1Hp = 746Watts, A cubic foot is 6.25 imp gallons

Having a 10cc pump, a 4" diameter pistoned ram with a 28" stroke, an 11Kw 3Ph motor and a honda 12Hp engine, will it work and what will it do ?

Pumps are usually rated in cc per revolution eg 10cc x 2850rpm = 28500/1000 = 28.5/4.55 = 6.26 gal per min

Flow in ImpGals per min x pressure in psi/ 1428 = Hp needed eg 6.26 x 2500 / 1428 = 11 Hp

psi x piston area in Sq inch/ 2240 = tons force eg 2500 x 12.57" / 2240 = 14 Tons This is the extention force, the retraction force will be lower by the area of the piston rod.

piston area x stroke = swept volume- SV SV/ delivery = speed of operation. So 12.57" x 28" = 352 Cu "/ 1728Cu" = 60sec /4.9= 12 seconds for full stroke.

Some figures have been rounded for simplicity..

The above figures were used to show that using the ram and pump, both the electric motor or the honda engine would power the unit giving a force of 14 tons and that its operating speed would be good at 12" travel in 5 seconds. What was it ? A log splitter. Noel.

2 ton fly press anyone?

My first one was made from box section, (which had once been the legs of a semi trailer  ) , powered by a 6 ton hydraulic jack.

I now use an ex materials laboratory specimen press, which has a 5 ton jack. The side standards are 1" round bar.

Only defect is since replacing the seals, the ram and moving platen have to be forced down by hand rather than gravity, but it leaks less oil, now!

Not often needed, but invaluable when it is

Howard  (Emojis – GRRRR   Its done it again! )

Edited By Howard Lewis on 03/10/2021 16:44:53

Edited By Howard Lewis on 03/10/2021 16:45:45

This looks easy to scale down and make as bench press. It also has the workpiece at the bottom ,safer in my opinion .Looks like it can be made without welding.

Maurice

I have been thinking about making one of these as well. I do have on of the metalcraft manual benders but its not really for things like 25x6mm flat bar.

Me too I discovered that I could buy the standard car engine hoist ram for not a lot.

It has a 19.5" stroke for broaches and supposedly delivers 8 tons.

Take that with a pinch of salt, but as my personal taste in broaches are all rated <2 tons it matters not.

I very nearly finished it but then I blew my CNC software and everything stopped