Hydraulic Press Pins

[I/Mx]

I picked up a 20 ton H frame today but it is missing the pins that support the bedplate. What grade of steel should I use for these ?

Thanks

 

[Hopefuldave]

What diameter will the pins be? channel or separate bars on the uprights?
You can find calculators for shear strength (usually a lot lower than tensile) in single shear, double shear etc - all depends on the press and how the pins locate in the uprights / under the bed - look up what you need for at least double the shear load for a margin!

I'm hoping to overbuild my 10-ton and picked 25mm diameter mild steel as being more than enough, the uprights are thickish-flanged channel and the bed's going to be pretty rigid (also sturdy channel, with the open side boxed in) so *shouldn't* spring, I hope no unexpected loading due to distorting the frame. YMMV as they say in the rebel colonies.

Dave H. (the other one)

 

[frank horton]

I just used 25mm black bar for my 25tonner.......and had it to the max loads'a times.....
it's only when u get down to 15mm dia u need the special steel.....
oh, my home made press has just about 2mm clearance between the bed and the frame legs.....

 

[Wedg1e]

We have a Clarke 10 tonner at work and the pins look like they've been run over by a train - they must be 20-25mm diameter.
Granted they haven't snapped but they are wonkier than Ken Dodd's gnashers.

 

[Hopefuldave]

I just used 25mm black bar for my 25tonner.......and had it to the max loads'a times.....
it's only when u get down to 15mm dia u need the special steel.....
oh, my home made press has just about 2mm clearance between the bed and the frame legs.....

I'll be putting some HDPE / PTFE pads, or perhaps some roller bearings to attempt to hold everything in position/alignment, and I've seen some cheap 20-ton air-hydraulic jacks on EvilBay, £55 so a bit tempting... Hoses, fittings and air valve will probably come to more
I'm thinking it shouldn't be too much more diffic' than turning a basic jack upside down to turn an air-hydraulic upside down, park it between the top crossmembers? The steel channel I'm assured should be good for way more than the jack can poke out!

Dave H. (the other one)

 

[pressbrake1]

I picked up a 20 ton H frame today but it is missing the pins that support the bedplate. What grade of steel should I use for these ?

Thanks

Anything really though given choice id use a grade with a higher tensile but with some spring
En8

 

[Pigeon_Droppings2]

Don't forget if it's got 2 pins then it's half the max load on each.

 

[slim_boy_fat]

When I built mine (I did a report here at the time) I used steel from a fabricator's skip, turned in the lathe to as big a diameter as I thought was reasonable.

Maybe I should have given more thought to loadings etc but I don't expect to ever reach maximum loads with it.

 

[armalites]

I'll be putting some HDPE / PTFE pads, or perhaps some roller bearings to attempt to hold everything in position/alignment, and I've seen some cheap 20-ton air-hydraulic jacks on EvilBay, £55 so a bit tempting... Hoses, fittings and air valve will probably come to more
I'm thinking it shouldn't be too much more diffic' than turning a basic jack upside down to turn an air-hydraulic upside down, park it between the top crossmembers? The steel channel I'm assured should be good for way more than the jack can poke out!

Dave H. (the other one)

You can't just turn a jack upside down, it needs some internal mods. Loads of stuff on the web about doing it.

I made a press with a bottle jack when I was young and it served me well but proper rams with external pumps aren't expensive these days and the reality is you can buy a complete press with hand pump and ram for £140

 

[Pigeon_Droppings2]

My DIY press build was going to use a porta power 10T ram.....you can pick them up cheap on ebay.

They're usually 10T I think....but then ebay did a big discount code and the rest is history....just wasn't worth building my own press.

This one is bid £50 on fleabay...got mine for £35 or something.

 

[Hopefuldave]

You can't just turn a jack upside down, it needs some internal mods. Loads of stuff on the web about doing it.

I made a press with a bottle jack when I was young and it served me well but proper rams with external pumps aren't expensive these days and the reality is you can buy a complete press with hand pump and ram for £140

Yep, done a bit of research, know about remote reservoir, know I'll have to move and flip the air-hydraulic pump, looked and the ram and pump packages.
The cheap Chinesium presses look a bit er, ramshackle to me and waste a lot of the height the way they attach the jack (until you get to the £400+ price bracket), and I#ve already skip-dived most of the materials and a manual 20 ton jack to get started with, the air-hydraulic is only because I'm lazy and feeble, can't abide pumping a handle for hours and sometimes need both hands free to hold the work

Dave H. (the other one)

 

[Pigeon_Droppings2]

Mine was a Chinese jobbie...it's a good solid build.

I got it on an eBay deal for £180...was going to build my own but I didn't like the bottle jack and springs...for £180 I'd struggle to justify the time to buy all materials and time to build....but it you've got all the bits then might be fun project.

Porta power ram would be similar I think to what I got.

 

[mike os]

Big as the holes will allow....anything will do, I use 8.8 bolts on my 32tonne