Diy hydraulic shop press

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xander janssen

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Today I converted an old hydraulic car jack and some rest material into a shop press.

No more pressing bearings and dowel pins using the bench vise, but a proper and stable vertical press.
 

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I have a monster one but sometimes it a pain with all the heavy stuff, I like what you built, neat and simple, I have the material, think I am going to build one like that, being you started this would you by the paint ? , just had to do that, thanks for sharing.
 
For final use it will be held in the vise to keep it stable.

One extra feature not to lose the lever extension which also serves as the handle for the release valve.

Will paint it one day with some leftover metal paint.

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You may want to consider adding a couple more pieces of angle to the lower half, this way you can have a "Table" to rest the parts on & let the press come up through the bottom & create some different press plates for removing bearings as well.

John
 
I made a press many years ago, theoretically a 20-ton press (that is the rating on the jack I used). One thing I have learned that you may encounter: it is hard to get parts perfectly centered with respect to the jack ... and consequently, it is very easy to have the press start to rack as pressure is applied off-center. This is true even though the cross pieces on my press are 8" wide - one would think that would provide plenty of strength to resist racking, but it turns out that 20 tons is rather a lot of pressure ...

All that to say, you may want to consider some angled bracing to help reduce racking. :)
 
With the icon of Wie E. Coyote, I can only imagine! :)

I seriously doubt that I've ever gotten anywhere near 20 tons in actual pressure applied. But even at less than 20 tons, it is quite amazing to see a solidly-welded structure racking into a diamond shape ... definitely not what one wants.
 
Today I converted an old hydraulic car jack and some rest material into a shop press.

No more pressing bearings and dowel pins using the bench vise, but a proper and stable vertical press.
How does it compare to one of those rack and pinion arbor presses? I had the impresson that they are relatively expensive.
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With the icon of Wie E. Coyote, I can only imagine! :)

I seriously doubt that I've ever gotten anywhere near 20 tons in actual pressure applied. But even at less than 20 tons, it is quite amazing to see a solidly-welded structure racking into a diamond shape ... definitely not what one wants.
It's funny all this should come up but I'm actually designing/building a 30T press at the moment. It's another guy's core design which I really liked just for it's rack/shear-proof nature. The main web is 1" thick plate. He cut out and welded up the 750lb frame as I can't weld 1" plate with my MIG and I'm designing/building the hydraulic system. It's a bit of a money pit but that's because while it's 30T it's also going to be fast too so the hydraulics & power are large. Amongst other things it will be for forging welding Damascus so speed is of the essence. It's also foot-pedal operated to keep your hands free for handling the hot metal. I will say it's been a tremendous learning experience about hydraulics....and financial planning. ;-D It should keep me busy for the summer.
 

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How does it compare to one of those rack and pinion arbor presses? I had the impresson that they are relatively expensive.
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Rack and pinion or eccentric press gives better feel since there is a direct mechanical link, where hydraulic gives you more brute force. I would love to have a small rack and pinion one day, but indeed price is rather high. For delicate jobs I will continue to use a small 2 inch wide vise to press tiny pins and bearings.
 
The rack and pinion type can be very convenient for pressing bushings in / out. If they are larger, they may work for broaching keyways - the smaller ones almost certainly won't be up to that task. And the opening of the throat can be limiting, again depending on the size.

In general, I reach for my small rack & pinion whenever the work is within its capacity, because it will be quicker (since my hydraulic is manually pumped), but it sure is nice to have the larger capacity (both size and force) when really needed.
 
Great ideas guys, but please note. PRESSES are designed to be STIFF under load. Not "just strong enough". It is the stiffness that keeps both anvils in line and parallel, to prevent the job from slipping. I have an hydraulic jack, pump needs fixing (it was a gift) but worked out appropriate steel for a stiff frame, and I would not be able to lift it!
I have pressed bearings out of motorcycle crankcases using a car jack between 2 walls in a stairwell, and inside a door frame. (We have brick-built buildings in the UK, not cheap wooden huts).
For model stuff, my 4in. Engineers vice does everything.....
But we'll done if the press does your job safely. The last thing you want is slippage to cause a broken casing, bent shaft or something .
K2
 
The rack and pinion type can be very convenient for pressing bushings in / out. If they are larger, they may work for broaching keyways - the smaller ones almost certainly won't be up to that task. And the opening of the throat can be limiting, again depending on the size.

In general, I reach for my small rack & pinion whenever the work is within its capacity, because it will be quicker (since my hydraulic is manually pumped), but it sure is nice to have the larger capacity (both size and force) when really needed.
One other note: the smaller rack and pinion style does come with one inconvenience that should be mentioned - it can be a bit of a pain to get the arm positioned optimally. Larger / commercial presses of this sort often have a clutch and handwheel mechanism that allows quick positioning of the ram and allows one to pull down on the arm, lift it up for more travel, and pull down again. (Hopefully that made sense ...)

Great ideas guys, but please note. PRESSES are designed to be STIFF under load. Not "just strong enough". It is the stiffness that keeps both anvils in line and parallel, to prevent the job from slipping. I have an hydraulic jack, pump needs fixing (it was a gift) but worked out appropriate steel for a stiff frame, and I would not be able to lift it!
I have pressed bearings out of motorcycle crankcases using a car jack between 2 walls in a stairwell, and inside a door frame. (We have brick-built buildings in the UK, not cheap wooden huts).
For model stuff, my 4in. Engineers vice does everything.....
But we'll done if the press does your job safely. The last thing you want is slippage to cause a broken casing, bent shaft or something .
K2
Yes, agreed!
 
One other note: the smaller rack and pinion style does come with one inconvenience that should be mentioned - it can be a bit of a pain to get the arm positioned optimally. Larger / commercial presses of this sort often have a clutch and handwheel mechanism that allows quick positioning of the ram and allows one to pull down on the arm, lift it up for more travel, and pull down again. (Hopefully that made sense ...)
Makes sense to me. I use my 3-ton arbor press daily as a cat-food-can crusher (I have five cats, so lots of little aluminum cans that I melt down periodically), and at the outset I had to adjust the arm to provide the optimum clearance and stroke. If I had to adjust it frequently, It would indeed be inconvenient, but I seldom need to move things.
 
When people are talking "press forces and ratings" it is easy to quote numbers without really appreciating what they mean. And if the frame is distorting then it may be strong enough not to fail, but is certainly not STIFF enough to hold its shape!

A 1.5Tonne jack will lift one end of your family car easily and safely. This force to lift - say the front under the engine/axle - would be on maybe a 2inch piston. But not lifting 1.5 Tonnes, as the load is not the jack's safe (quoted) limit.
My Compact Suzuki is only 1.5 Tonnes when wet! - Roughly 1 Tonne front, 1/2 tonne rear axle.
A Mitsubishi Truck may be able to pull a 3.5 Tonne Horse box - including the horse. It will only weigh maybe 2.5Tonnes itself? - But is rated for braking to be able to stop the gross weight of 5 tonnes... - even though you may drive so you only use maybe 1 tonne of braking force - fully laden? (0.2g decelleration to stop the horse falling over?).
A truck for hauling a 30 Tonne trailer may be 10 Tonnes ?....
The trailer complete with all the goods on board may be up around the 30 tonne region... So a big hydraulic system from and old truck jack is what we are talking about to apply a 30 tonne lift... Just look at how much metal is used on the truck's axle members etc. to get a good idea of the forces required by seeing the metal used to manage these forces. As the 30 tonne trailer will have maybe 3 axles, each axle is managing 10 tonnes... Is the 30 tonne press built like a truck axle or stronger?
Cheap mild steel has a 20 tonne tensile strength, good stuff has a 40 tonne tensile, and "stronger steels" up to 100 tonne.... but that is the Ultimate Tensile strength derived in tons per square inch.
To make a 30 tonne jack, you need everything stressed so you have way less than the tensile strength of the material managing the forces. A 1 inch 80 tonne bolt will strip threads or snap at maybe 30 tonnes, as there isn't enough steel to withstand 80 tonnes: that is just the rating of the steel used to make the bolt. And threads have stress raisers that quadruple the stress in the material, so you can consider a 1/2 inch bolt in "80 tonne steel" to go "ping" at maybe 8 tonnes? - Depending of tensile/bending/shear loading...
The "20 Ton" press where I worked as a lad had a pressure gauge - indicating the hydraulic pressure applied on the 3 1/2" ram.... It had 2 main steel legs at least 6" diameter to take the tensile forces when in use, and retain the STIFFNESS required for any off centre loads. One day my rig slipped because it was not EXACTLY square and true to the alignment of the pressing job, and flew across the workshop and hit the steel cladding with a loud "Bang". - Nowadays we have guards in industry, but the Boss gave me a stern lesson in safety and care when doing any job after that.
Looking at the frames shown, I guess they will likely distort after little more than 1 tonne applied load? I'm OK, watching on the computer, but please be careful if trying to apply such huge loads as you are discussing. When the load is applied the frames distort and then everything is a big spring of stored energy awaiting some point where it goes out of alignment and slips, when it fires small metal bits like a catapult!
I suspect your 2 tonne jack is only applying 1/10th Tonne load to press in a bearing, or it would destroy the bearing and housing?
I have been in a small group where we used a car as a jack to press-in a small job, simply jack the car up (front-end with a screw jack), fit the bits beneath the frame and road (with bricks and wood packing) then lower car gently (easy with a screw jack) and it pushed the shaft into the next bit of the assembly. (may have been a bearing? - I can't remember!).
I removed and fitted crankshaft bearings on motorcycle crankcases using similar methods - in a stair-well between 2 walls at the apartment block where I lived. More than 2 tonnes load would have pushed the walls out!
So be careful with how you describe the strength of these flimsy frames...
Of course, Manufacturers have reputations, safety legislation etc. to consider when they make and rate their goods. We do not always follow those rules (do we even know the rules?) when we make stuff in the workshop, so just be careful.
K2 ;)
 

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