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Using a forklift cylinder for a press?

tyleradambrown1

Plastic
Joined
Aug 13, 2019
I apologize if this is in the wrong place this is the first post I've made here, but I've been a long time lurker.

Basically has anyone used a forklift cylinder as a shop press? I have one laying around and I thought it could make a good press cylinder, but I'm unsure of the PSI or the tonnage, I also have the mast and that looked like it would make a good press frame, just curious if anyone has ever done this it's off a 50's allis chalmers 5000lb forklift.

Thanks,
 
Let me guess, it will press right around 5000 lbs....

BUY a cylinder that does what you NEED.
 
Yeah it goes all the way up, I'd guess 5' but my shop has plenty of ceiling height, plus I thought it would be pretty sweet to have 48ish inches of travel.
 
That's what I was thinking also, but I thinks it's like a 3" bore, I don't have it with me at the moment but I'd guess it's around that bore size at 2500psi I think that should get me around 8 tons. seems crazy to me that they would build it like that but maybe in the 50's they had a different set of rules.
 
Maybe I don't get the full gist of the press idea, but the mast cylinder on a typical forklift is single acting. Hydraulics shove it up, but Mr. Gravity brings it down. How would that work for a shop press?

Stuart
 
Most older forklifts use a pulley arrangement on top of the cylinder so the forks move twice as fast as the cylinder. That means a 5K capacity forklift actually makes 10K of force at the cylinder.

But I still think you're wasting your time. I see really nice presses for sale here for little money. I bought a 50 ton Ramco for $50. It just needed a seal kit.
 
I know if I had that much travel, the first time I used it would be my last. The ram would bend and shoot the piece right at me. Scary enough with my wimpy 8" at 60 ton.
 
Interesting that makes sense it is on a pulley system, what are you're thoughts on using the mast as a frame for the press? seems like it's already setup for a good H frame just need to add a crossbrace and a mount for the cylinder.
 
Better to use the complete mast as an elevator. I was in one guys shop and they had a car elevator made from a large forklift mast. The entire second story was filled with antique cars.
 
That's what I was thinking also, but I thinks it's like a 3" bore, I don't have it with me at the moment but I'd guess it's around that bore size at 2500psi I think that should get me around 8 tons. seems crazy to me that they would build it like that but maybe in the 50's they had a different set of rules.
Crazy dood...assuming 2500 psi

try 5000 lb load x 2 (2x for the chain/pulley mechanism)
:nutter:

and what doo you want to doo with a 10,000 lbs/5 ton press ?
 
Better to use the complete mast as an elevator. I was in one guys shop and they had a car elevator made from a large forklift mast. The entire second story was filled with antique cars.

Which gave the insurance company a giant "out" you could drive an ocean liner thru when paying a claim there,
for anything (fire/theft/damage etc.)
 
Yeah it goes all the way up, I'd guess 5' but my shop has plenty of ceiling height, plus I thought it would be pretty sweet to have 48ish inches of travel.

Do you have the need for a 48" push? I work on a lot of big stuff, and never has a need to have that kind of push/pull stroke been needed.

Could you instead build yourself a tall press frame with a bed that is relocatable if you have large pieces and use push blocks to get any supplemental length you need?
 
you can use the cyl and mast channels as a basis for building a shop press. most forklifts of that era use about 2500 psi. a 3" bore will net you about 17 tons of force. a 4" will get you about 30 tons. most of those old lift cyls can be easily shortened the base end is welded on and can be remove by grinding or cuting the weld off. cut the tube to length i would use about 24" of stroke and reweld the base back on .the hyd port is usually in the base if not you will need to buy or make a new bung and weld it into the tube. there is a special fitting in the hyd port called a lowering valve. its a safety device that prevents the mast from crashing down in the event of a broken hose or fitting. you can discard this. this is a single acting cyl but you can convert it to power return. you will see a small fitting near the top of the cyl, this is used as an overflow return for fluid that gets past the piston packing. you can use this for a piston return line if you use a pressure reducing valve to limit the return press to about 150-299 psi. the packing gland seals probably wont take much more than that.this can be a very satisfying project but if you aren't qualified to do this kind of work and you don't have access to free parts then go to harbor freight and buy a press.
 
unless your in the 40 or 50 ton range a cylinder is the least of your costs. and few things are more annoying than not being able to fit the piece your pressing between the uprights so you set it up in front of the press and use a sledgehammer. you can use the barrel and shaft though to make a proper cylinder if time is in abundance and money is not. I used a 5' stroke excavator cylinder on mine. shortened it down to 20" stroke.
 








 
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