Press Build

For a 3" cylinder (9 ton press) a 2hp 1800 rpm motor works just fine. Even for a 4" cyclinder (12 to 16 ton press) a the same motor seems to work just fine, but a 3600 RPM motor would be best. A 11 to 13 GPM 2 stage pump is the normal pump used for presses of this range in size. Note most 2 stage hydraulic pumps are rated for flow at 3600 rpm at 1st stage (low) pressure. A 13 gpm pump will only be pumping 6.5 gpm at 1800 rpm which works just fine with a 3" or 3.5" cylinder, but is fairly slow with a 4" cylinder, but still works ok (that is my setup).

There are some hydraulic motor/pump packages you can purchase, or purchase the motor & pump separate. It's really good to use a 56C motor so a "bell housing" can be used to mount the pump to motor. This takes care of any mis-alignment of pump/motor shafts.

The least expensive route is to use a compressor motor (not TEFC), but those are not 56C frames so an "L" bracket is normally used to mount pump.

Wait, I'm writing more than was asked -

Ken H>
 
Best price around for a 4" cylinder ($133 shipped):

Here's a decent price on pump and mounting adapter if you're planning a 56C motor ($175):

About best price on a 2hp or 3 hp motor but the mount on the above package won't work ($150) :

https://www.northerntool.com/shop/tools/product_200660730_200660730 ($165)

A log splitter type control valve is needed ($110): https://www.northerntool.com/shop/tools/product_472_472

You'll also need an oil tank, 5 gal is what Coal Iron uses on 12 & 16 ton press:
https://www.northerntool.com/shop/tools/product_200665136_200665136 ($160)

Those are general prices and you might find better somewhere, but those links will provide an idea what to purchase and prices. Now you're ready for the expensive part - steel.
 
WOW!! This thread has gotten real serious!!
I got wrapped up in other stuff and forgot to mention this post - YES, it did get serious and a lot of good info was shared. I really do say a big THANK YOU to 52 Ford for his simulating the stress in CAD. Gave a lot of good info on the H style press frame. A "C" frame would be totally different.
 
Yep, a 56C motor would fit nicely. Given a choice I'd go with a 3600 rpm motor to get the full flow rate from the pump, With your 3.5" cylinder the 1800 rpm motor will work good.
 
Yep, a 56C motor would fit nicely. Given a choice I'd go with a 3600 rpm motor to get the full flow rate from the pump, With your 3.5" cylinder the 1800 rpm motor will work good.

This is a practice run Ken I plan on building a larger 16-24T press eventually (I think? LOL!). Wanted to build this figure out what I really want and what I should add or change, sell this one. Hopefully recoup my investment on this and hopefully have a couple bucks to put towards the larger one? But this may be fine for me?
 
You sound like me when tackling something new - ease into the project cheap, then when it works move to final project.

You will be surprised what you can do with that 12 ton press. Run it at 12 ton (2500 psi) for a while and see how it works. Then if you're feeling brave (and the welds are really good) crank it up to 3,000 psi (not recommended) for 14.5 ton and see just how much difference it makes - not as much as you might think.

If you've got the room for a "big" press, I'd plan the next to be a 4 or 5" cylinder with a 3600 rpm motor to get full flow from pump. A general ROT if a 4" cylinder for 16 to 20 ton with a range of 2500 psi to 3200 psi, and that will work with a 2hp (1800 rpm) to get by with 3 hp (best) 3600 rpm motor. A 5" cylinder range will be 24 to 31 ton in the same 2500 to 3200 psi range. I would wish to hold my max pressure <2500 psi, even with hoses and cylinder rated at 3500 psi. Less stress on everything, and if you have a leak a 2500 psi spray is a tad less dangerous than 3200 psi spray.... I think it would be anyway.

All this talk is making me wish to build a press myself from scratch, but this mod'd Coal Iron press is all I need, and it allows me to roll outside to work, and back inside for storage.
 
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Keep in mind, I made a LOT of assumptions and took a lot of liberties when I modelled it. So these images don't really mean all that much in the real world. I will say, it's not a project to practice welding on. If you see any porosity, slag inclusion or any other sort of defect, I'd grind the weld out and start over....

The deformation in the images is exaggerated. The "max" number is the actual deformation.

For the off center load, thats 32,000 pounds on a 2" diameter circle placed 3 inches off center. Sketchy. Put's a lot of stress on the welds, trying to tear them, where a centered load is trying to shear them, mostly.2inchcoalironinsidecorner.jpg2inchcoalironoutsidecorner.jpgcoaliron3inchinsidecornerdeformation.jpgcoaliron2inchinsidecornerdeformation.jpgcoaliron2inchoutsidecornerdeformation.jpg3inchoffset2inchcoalironinsidecornerDISPLACEMENT.jpg3inchoffsetload2inchcoalironinsidecornerSTRESS.jpg

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Oops. Too blurry to read some of the numbers. 0.045 thousandths displacement on the top right corner with the off center load, 2x1/4" angle iron, and the corners of the angle iron facing in.

The images that are taken from an angle are showing contact pressure. Shows how the stress is concentrated on the welds, pretty well.

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Yea, I was struggling trying to read numbers. I could get the 0.0???, but wasn't totally sure of other number. .045, that's over 1/32", good bit of movement.

I understand about computer simulation vs real world. Just like modeling a transmitting antenna, real world is different, but still computer model gives a VERY good idea if it will work or not.

Thanks again,

Ken H>
 
By the way, the offset 16 ton load on the 2" angle iron would still have held together. Getting REALLY close to not holding, though.

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That was my idea from looking at the numbers on the off center load. While the press would have held together, it would still have stretched over 1/32", not sure how many times that would hold up with that much stress without permanent deforming. Important to keep load centered.

I think you've pretty well shown the 2"angle is ok for a 12 ton max press, but not for a 16 ton press. I know if I were building I'd be using larger angle. Just not that much difference in cost or weight, but lots more strength.
 
Well most of the welding is done. Dug out bad 7011 hit it again, wire wheeled it then capped it with 2 runs of 6013. Gonna weld lower die plat on then after I get press running I'll run the ram down line the upper plate with the lower die plate as good as I can then weld that so hopefully everything will line up when I run press??
 

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I think that'll hold your 12 ton with no problem. Looking good. I see bolts in bottom, are you planning to bolt your dies in the way Coal Iron does? It didn't take me but a week or so before I changed to a quick change die holder so the dies could drop in. After a couple of passes those dies (and bolts) get so hot you can't hold even with heavy gloves.

Yes, you got the right idea, weld bottom plate on, run ram down so the top can easy be lined up to match bottom plate, then tack weld the top in place. Now you can move around, lay down, etc for best welding position.

I know you're excited to get it going. Maybe this weekend? Gotta watch Bama football Sat. The wife's family aren't "fans", they are "fanatics" on Bama football. Me, I'm barely a fan, but I do a pretty good job of pretending to keep everybody happy {g}
 
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