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Patch
08-12-2011, 06:12 PM
Some time ago I read about turning a hyd jack upsidedown for a small
press. I can't remember if it was this forum, the PM or at Miller.

Basic breakdown of jack with inverted internal suction tube into resevoir.

Any ideas of info where-abouts?

Anyone here ever made this retrofit?


Thanks,

davidwdyer
08-12-2011, 06:38 PM
I remember it was on this forum somewhere.

I did a 20 ton one time. Just stuck a little copper tube from the intake hole up to the top (which became the bottom). Today, with more equipment I think I would thread something in instead of just forcing the copper into the hole. :eek:

Patch
08-12-2011, 08:36 PM
Thank-you David,

I wasn't sure.
Did a search query and found the one I was thinking of. The information will be helpfull.

The intention of the upside-down jack will be utilized on a cantilevered single post press.

Thanks again,
Patch

Dunc
08-12-2011, 11:17 PM
The Feb 1968 issue (p 146) has an article about using an inverted hydraulic jack and making a reservoir

Don Young
08-13-2011, 12:03 AM
One way to do it is to install a fitting in the fill hole and connect a reservoir above the jack. Bleed all the air out by working the jack on its side with the filler hole on top. Ready to go!

It does help to modify the pump lever linkage so it pumps on the down stroke.

Carld
08-13-2011, 12:42 AM
I did that to a 30 ton Blackhawk jack about 20+ years ago. I stripped it down and drilled out the pickup hole, tapped it for a 1/8" NPT fitting and put a tube reaching to near the top cap, turned the sleeve upside down and cleaned and assembled the jack and it's been working ever since.

It's mounted in a frame my father-in-laws brother built for their farm but threw away before they even used it because they found a 50 ton factory made press.

I grabbed that frame faster than you could say damn, I need that.

Patch
08-17-2011, 02:03 AM
Just an update:

Dunc,
I found the article as you mentioned on google-books. Interesting read and T.Y.

Don,
I may need resort to that method and Yes, I will need to invert the pump lever linkage. T.Y.

Carl,

Have you still got the frame? If so, are you using it as a press with above mentioned procedure?

The jacks I have are Norco brand. They pose a dilema such that the barrel and base are fully seam welded as a unit. An internal tube would not be feasable. The piston is removable thru the top of the barrel and is
rebuildable if need be.

I have the parts/use manual for the jacks. Somewhat helpful for internal parts but, clarity of feed pickup and location within the barrel/base is not disclosed. Hopeful intentions are to drill thru the base bottom to install a rigid pipe and into a resevoir.

I have recently Emailed Norco for additional information on the internal oil -
ways (such that they are not drilled thru) and as I wait, continue to fab post assembly.

A possible last ditch method:
To build a two stage valve body and use an extended hyd. cyl.

Hope to hear from Norco soon,

Carld
08-17-2011, 10:01 AM
Yes, I still have the press and used it yesterday to straighten the plate on a retaining pin. The jack will slide from side to side so I can position the ram where I want it. Here's a photo of it.

http://i82.photobucket.com/albums/j276/yeathatshim/P8170004.jpg

Don Young
08-17-2011, 10:43 PM
I certainly would not consider any drilling of the jack without being able to disassemble it to verify the passages and clean out the debris.

All it takes is a piece of metal or flexible tubing, a simple reservoir, and some sort of liquid-tight connection to the fill hole. A piece of vinyl tubing, a soda bottle and some sort of adhesive caulking would do it. Nothing needs to be done inside the jack. With the jack body full of oil (air bled out) it will always feed oil to the pump, the reservoir being needed because the volume of oil in the jack varies as the ram moves in and out without any air space to accomodate the volume change. The reservoir level needs to be kept above the bottom (new top) of the jack to ensure reliable oil feed. It is best to have some sort of filtered air vent on the reservoir to keep the oil clean while allowing air into and out of the reservoir.

I have never seen it but it would be nice to have some safety cables through those springs like they do with garage door springs. That would keep the parts restrained if a spring shold break. I may do that on my press as I get kinda skittish when those big springs are fully extended.

Carld
08-18-2011, 12:28 AM
If your referring to the springs like on my press you need not worry. at full extension if an end broke it would simply hang there or fall in the floor if both ends came off. It not under a great amount of tension.

As to using an external reservoir it would be extremely hard to get all the air out of a jack turned upside down. It's simple to tear down, drill and tap, put a pickup tube in and reassemble if the jack has a removable sleeve.

If it's a fixed sleeve then find a jack with a removable sleeve.

winchman
08-18-2011, 02:24 AM
That's a press you can hang your hat on.

Carld
08-18-2011, 09:17 AM
:D and I do. It's a chip deflector for when I am turning in the lathe and the chips are flying and some like to get over the top of my safety glasses into my eyes and on my head where hair used to be. Grab the hat, pull bill down to glasses and keep on cutting. Sometimes I have to button the collar on my shirt to keep chips out.

Patch
08-18-2011, 11:57 PM
Animated hyd. jack I found while searching the net.

http://www.hyjacks.net/animation.gif


Carl,
That's a nice press. I do like the fact your jack can move laterally.
Question: What method are you using to secure the jack base to the
trolly? Welded? Bolted? Slip plate?

Don,
An air filter of some sort certainly would be a good idea to include.

Carld
08-19-2011, 10:34 AM
The jack base is threaded and the plate is bolted to the jack. I never have painted the press because it has a pleasant patina to it and paint won't make it work better. The only improvement would be a crank to move the table up and down. As I get older the table seems to get heavier.:rolleyes: