Hydraulic Press upgrade

I have a typical 20 ton press that uses a bottle jack on top.

Similar to this below.




But with this style, the movement of the press point has lateral movement because of the need of the bar to ride up and down within the rails. Too sloppy.

I looked briefly into converting over to the style where an inverted piston cylinder is mounted to the top and there is no riding support beam below. See pic.



Found out from where I was looking was going to be huge money.

Anyone built this type and can recommend an economically attractive (notice I didnt say cheap!!!) way of doing this???


Thanks,
Ken J

I think you can pick up a cylinder and hand pump from ebay for less than $250. Enerpac is my favorite brand.

Otherwise, can you extend your guide rails down and tie them into the plate you place on top of the platten?

If the side frame channel is sufficiently accurate reworking the jack support plate to incorporate a set of three rollers on each side adjusted so as to thrust against the insides of the channel may give sufficient control. Pretty easy to fake up for test purposes. This is what I shall do when I turn my pile of "obtained" parts into a press.

Swanky version uses a pair of rails as accurate as maybe fitted inside the channel with extended side plates and, possibly, a top spreader too. This allows two sets of rollers to be used each side. Considerable fitting and fiddling to get right. A large triangular guide, lathe Vee bed style, might be as effective.

The direct acting type aren't immune to lateral alignment issues although in this case the forces try to bend the ram. Careless set-up can wreck things. The el cheapo jack type may be painfully floppy but they are pretty resistant to "D'oh moment" damage.

Clive

i would get a hydraulic cylinder from surpluscenter. 20 tons is a lot of force, most of the jack type units have a hydraulic advantage built in. heck you could even skip the mechanical handle and add an electric driven hydraulic pump for not much more money.

Stop mucking about and just buy a Dake 50 ton press



I say 50 ton rather than 25 ton as the 50 ton has the ability to move the head sideways on rollers...very handy feature. And the press beams, far as I know the side posts are close enough fit to prevent lateral movement. On some presses, the support posts mount via holes from beam directly into the holes in the side rails to solve that issue.

A bottle jack can work upside down too. This gives you a straight ram, as steady as a bottle jack ram inherently is. I cannot understand why they insist on building those presses the way they do.

I wrote some words and posted a pic about how to do this a few years ago on another site. That pic still racks up dozens of hits weekly; I can't imagine where it has been reposted.

Here:

Jack anatomy:



...and a closer look at the base plate. The base plate has a number of holes / vents / valves (and loose balls). One of these is the intake for the pump, to suck oil from the reservoir. If this hole had a tube or hose attached to it ( = snorkel ) then it would suck oil from the top of the reservoir. Good thing that, because when you turn it upside down...



On a similar thread a few years ago, one of the posters ( I forget who, but it was a nice press. Yellow.) added a nice touch... He took a pressure guage and just tapped it 1/8 NPT right into the center of the base plate. (which then is on top, since the jack is upside down)

Another thing... That screw extension on most jacks just enters a peened-in nut in the arbor. Some careful grinding with a Dremel will let you remove it, or make alternative tool fittings.

Doc.

.

Good info, Dr Rob.

I have the 50 Ton version of this.



If you can score a Porta power unit for the right price, the rest would be easy. There are no rollers on this slider, just 2 pins on the back and a threaded pin on the front. When you want to lock it in position you tighten the threaded pin. Unscrewing the pin allows you to hang it in the open part of the frame, or take it down to use as a porta power ram.

As previously noted by Rob, hydraulic jacks are quite easy to invert, & all without hoses

This does 20 ton with aplomb.





regards

Brian

Hi Dr. Rob

Im using a Princess Auto air over hydraulic 20 ton bottle jack. It says verticle only.

So from what youve found, can I mod it in order to turn it upside down?

That way I can mount the base to the top part of the frame like the fancy ones and its Miller Time!!!

how much monkeying around do I need to do inside?

Thanks,
KJ

Mud said:

Good info, Dr Rob.

I have the 50 Ton version of this.

If you can score a Porta power unit for the right price, the rest would be easy. There are no rollers on this slider, just 2 pins on the back and a threaded pin on the front. When you want to lock it in position you tighten the threaded pin. Unscrewing the pin allows you to hang it in the open part of the frame, or take it down to use as a porta power ram.

Click to expand...

This is a nice set up. As a "MECHANIC" (sarcasm from previous post intended) the option of moving the force and with the proper frame expanding the center width is very nice.

don't flame me but my neighbhor has a harbor freight press. same basic design as yours but the bottom of the jack sits on a piece very similar to the adjustable table. It is located at each end by the vertical supports. So it can move about 1/4" side to side and front/back. I would use some shims/wheels to reduce slop but it works. has a 3/4" pin welded to the bottom of a 3/8" plate the jack sits on top of. The jack is not held in place except by gravity and those retraction springs.
I think the extra beam is two pieces of C channel bolted back to back with some spacers and the plate(jack resting pad) is bolted or welded to the top flanges.
Bill D.

- Harbor Freight Tools - Quality Tools at the Lowest Prices

This one shows promise for adapting to a longer stroke cylinder
- Harbor Freight Tools - Quality Tools at the Lowest Prices

Thank you.

Lots of cred to Pistonskirt / Brian, whose press inspired mine. Brian, didn't you have a trick for flipping the pump lever mechanism 'round as well, or is my memory failing?

Fireguy, I really don't know. I only wanted to point out the fundamental simplicity of bottle jacks. Various makes, models and mileage may vary.

Many others here on the forum know more about this than I do, and can have suggestions for electric pumps / AOH systems etc.

I would suggest buying a cheapo jack, solely for the sake of taking it apart just to mess around and get ideas.

A thought though... clutter bugs me. I like clean. I was thinking that maybe those external ram return springs could be moved, to maybe reside inside the jack housing. Hmm.

Another thought... The larger bottle jacks, twenty tonish sizes, take a long time to get anywhere when pumping manually. There oughta be a way to increase stroke without too much effort, like BillD just said.

Gotta go.

PS: These jacks can be used for simple pneumatic stuff too...

.

Dr. Rob said:

Lots of cred to Pistonskirt / Brian, whose press inspired mine. Brian, didn't you have a trick for flipping the pump lever mechanism 'round as well, or is my memory failing?

Click to expand...

Thanks Rob, I did not pick up on your mention of "a yellow press" in your first post, it was a few years ago that I posted the details of my little press, over on the "other" forum if memory serves.

The lever mechanism modification is shown in my second pic, it is simply reversed on the clevis pin pivots (with suitable mods to the pivot rod) so that it strokes in the opposite direction.

In most cases all that is required internaly is to add a very light spring to the none return valve ball & (as you have shown) a suction pipe from the original oil inlet port.

Dr. Rob said:

A thought though... clutter bugs me. I like clean. I was thinking that maybe those external ram return springs could be moved, to maybe reside inside the jack housing. Hmm.
Another thought... The larger bottle jacks, twenty tonish sizes, take a long time to get anywhere when pumping manually. There oughta be a way to increase stroke without too much effort, like BillD just said.

Click to expand...

Internal ram return springs are difficult to get right particularly if the ram has a decent length of stroke, it also makes assembly a real pain in the arse.
The larger (60 ton) press that I built had two stage pumps but that adds a lot of cost / complexity & was remotely mounted thus involving external pipework.

Although my present unit does not take much time to pump down & does not bother me for the relatively small amount of press work I do these days, I do have a 50 ton bottle jack which (if I ever find time ) will be similarly modified.

The solution I have in mind is to mount a double acting air cylinder where the pressure gauge fits on my present unit with the air cylinder shaft passing down through a suitably sized double lip seal in the base housing with its end screwed into the press ram. An extra none return port with ball & very light seating spring would be machined into the base plate which may require it's own suction pipe.
With a regulated low pressure air supply via a simple switching valve the pneumatic cylinder extends the press ram & displaces oil from the reservoir to the hydraulic cylinder via the additional none return valve, to retract the press ram the main return valve has merely to be opened in the normal way as the air cylinder switching valve is reversed.

Should work quite nicely & keeps the unit self contained apart from a couple of nylon pneumatic lines so that the unit can be easily moved sideways within the press frame as required.

That is all probably as clear as a bowl of oxtail soup....but I think that I know what I mean

regards

Brian

Process of connecting ports power to jack

Mud said:

Good info, Dr Rob.

I have the 50 Ton version of this.

If you can score a Porta power unit for the right price, the rest would be easy. There are no rollers on this slider, just 2 pins on the back and a threaded pin on the front. When you want to lock it in position you tighten the threaded pin. Unscrewing the pin allows you to hang it in the open part of the frame, or take it down to use as a porta power ram.

Click to expand...

Would you have a diagram to show how to do this.

There is typically not a lot of engineering that goes into the pump chamber of a bottle jack. They are intended for very occasional usage. So you mess around replumbing the thing just to have it go for a crap later on. I'd use a porta-power style hand pump and a conventional cylinder first, if not happy with using a bottle jack in the conventional position (upright).

My Jack has a air assisted hand pump with a release valve I want to hook it to a hydraulic power unit 1.3 gpm at 2000 psi. I need to know how to connect the release side.

Dr. Rob said:

That screw extension on most jacks just enters a peened-in nut in the arbor. Some careful grinding with a Dremel will let you remove it, or make alternative tool fittings.

Click to expand...

Another way to remove the screw extension is to wind it out as far as possible and saw it off, leaving a stub threaded in. Use a chisel or something to get a bite on the stub and screw it in until it falls in. You lose a small amount of length but you don't have to be so careful. :-)

I have seen guys directly thread the small hole 1/4-28 and similarly thread some 1/4" hydraulic tube, then use threadlocker and solidly screw in the tube, which then becomes a dip tube when cut to length.]

metalmagpie

Also, this guy did a good job making a crossbar that had enough slop taken out of it so that he can still align punches and have them stay that way:

Stagesmith

metalmagpie

ccwheat said:

My Jack has a air assisted hand pump with a release valve I want to hook it to a hydraulic power unit 1.3 gpm at 2000 psi. I need to know how to connect the release side.

Click to expand...

Well, what pressure does the jack operate at ?

It is a 50 ton jack but I don't need that much. I think I can generate 12 ton at a1/2" per second. I believe that I can bypass the air over hydraulics and go directly into the jack it has a pipe coming off the side that I believe will release the pressure.