Medium Sized Hydraulic Press Build

Nick, I'm essentially trying to copy the capability of this machine, but in an H frame style like you posted. They don't give a lot of details on their components, so some of my choices were guestimates and calculating the theoretical results they'd give, since the only thing I really know about this press is the motor size and that it uses a logsplitter pump with 11 GPM high range. But there are videos of people using this machine demonstrating it's capability.

http://www.coaliron.com/forging-presses/16-ton-hydraulic-forging-press

Kuraki that press looks great too...I like that it seems to mostly be cut from a single piece of thick plate steel, which could be a good one for the water jet shop here. I also like that they emphasize that it can be moved around and isn't too loud, so good for residential areas.

I'll probably be laying this out all 2d and then having the pieces waterjet or plasma cut depending on design and required thickness of steel. I'd also like to use a combination of heavy bolts/hardware as well as welding for the final assembly. CNC plasmas tend to max out around 10-12mm (roughly 1/2" max) steel thickness around here, so I'll probably use multiple 1/2" plates or a single thicker plate cut at the waterjet shop.

Though I've heard that the C style presses are more user friendly, I'm still drawn to the H style for one reason or another. Once I have the necessary part requirements and general design idea I'll try to make a diagram showing what I'm planning.
 
I did model up a C frame press. They're essentially log splitters, really. And my biggest concern is the clearance and fit between the shuttle and whatever rail it rides on, and how that holds up over time. I changed my mind to building an H press simply because it's easier to engineer to be sufficiently stout without over engineering it. The C frame looks simpler, but I think is more dependent on good design. H is pretty hard to screw up. For what I intend to do, I don't think I need the open ended C frame, so I changed my mind on that.

I'm close to done:

1QYrKQO.jpg
 
24 tons is pretty much the minimum ... 30 even better. 1 IPS is the ram speed you need for moving much steel per heat.
Yes, people have built smaller and slower presses, but they have limitations.

A 3HP electric motor and a 16GPM pump are what works well. The bigger the ram, the more GPM it will need to move it. I see a lot of posts claiming much higher tonnage than are likely with the drive pump and motor shown. The speed on many of them would end up quite slow, too.

Many folks use the maximum pressure rating of the cylinder as the power of the press. This will only be so if the GPM and pressure are at the max. Use a smaller or slower pump/motor and the tonnage will drop a lot. On things like bottle jacks, the rated tonnage is pure hype. It can be compared to the 10 atmosphere waterproof rating of a cheap watch. It is very much less in reality. Another comparison is the HP rating of a shop vac. It says 5HP, but uses 10 amps at 120V ... do the math, it won't work. That would be a theoretical max of 1.6HP if it was 100% efficient. In reality it is more like 1.2HP. A 5HP motor running on 120 volts uses 31 amps.

Batson's book is written by an engineer who makes knives ... Batson - so the numbers and tables are proven, not hypothetical.




Here is why I don't ever recommend a bottle jack forging press:
One thing that many don't understand is how an air over hydraulic jack works. The air pushes an air cylinder, which pushes a much smaller hydraulic cylinder. Using a series of check valves, it increase the hydraulic power to the jack ram. The trade off is that the jack ram moves very slow. ( I have done the math and have never been able to see an air-over jack being able to create even half the tonnage rating in any reasonable amount of time. I think the rating is the weight that it can support without being destroyed, not the actual weight it can lift.)
Ignoring that, the air needs to be at 120PSI, and the air volume needs to be a sufficient to not wait all day for it to move the ram an inch. It takes a minimum of a 2HP shop compressor delivering 6 cfm at 120 psi to run a bottle jack forging press. Even then, the ram only moves fast under no load. Once it meets resistance ( the hot steel), the ram speed drops drastically. This is when the ram pressure starts to build. The full tonnage may not be reached for as long as a minute, and long before then the steel is too cold to forge. Smaller compressors deliver much less cfm and psi. I would think a 5HP shop compressor that delivers around 10 cfm at 120 psi would work good .... but the ram speed will still be slow.

Stacy thanks for the informative response. I think I really needed to hear, in that descriptive sense, exactly why I should finally drop the idea entirely for a bottle jack press. I really think a part of me was still considering building a quick one to tide me over ;)

Also really good to know the minimum cylinder, motor and pump sizes. I think I'll go with the minimum you and The Count suggested, 24 tons, and 3hp motor. On 220 volts 3hp only draws 10 amps if I recall correctly.
 
Yes ... 10-12 amps depending on the efficiency.

You will never regret building a proper press. It has far more use and ability, too. In the long run, you can sell it for more than you spent.
 
I did model up a C frame press. They're essentially log splitters, really. And my biggest concern is the clearance and fit between the shuttle and whatever rail it rides on, and how that holds up over time. I changed my mind to building an H press simply because it's easier to engineer to be sufficiently stout without over engineering it. The C frame looks simpler, but I think is more dependent on good design. H is pretty hard to screw up. For what I intend to do, I don't think I need the open ended C frame, so I changed my mind on that.

I'm close to done:

1QYrKQO.jpg

Mockup looking good! I totally agree with the H style seeming much harder to mess up. Interested to see how this comes along. This seems to be fairly compact as well. What overall height do you think it's gonna come to?
 
If I put it up on casters I think it will be about 40" to the top die plate. I still have to model a frame and casters and oil tank.
 
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. CNC plasmas tend to max out around 10-12mm (roughly 1/2" max) steel thickness around here, so I'll probably use multiple 1/2" plates or a single thicker plate cut at the waterjet shop.
I hate to be the bearer of bad news but waterjet cuts thick materials extremely slow. This will cost you a fortune to have done. Even with 1/2" thick. A cnc plasma should have no issues cutting 1" thick steel. It's extremely fast and more economical than a waterjet. For 1" steel your waterjet pierce time alone is like 30 seconds. That's like a half a pound of media! I have a waterjet at work and take thicker material to the plasma table, and that's free to use for me.
 
Viper not yet but I'm happy to put one together once I get clear on my final parts list and overall design. If you're referring to Kuraki's he listed some of his parts above
 
Viper not yet but I'm happy to put one together once I get clear on my final parts list and overall design. If you're referring to Kuraki's he listed some of his parts above

I am thinking of one like posted above, H frame, ram on bottom, 24 to 30 ton, 230 volt motor, I would greatly appreciate a current list, even better a build along thread. I to would like to build it the correct way once. Thanks in advance.
 
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When I get to that point I'll share. Mine only exists in my computer at this point.
 
Ok. Here's my hydraulic component shopping cart. I think this is everything I'll need to purchase outside of hoses, which I'll do once I've assembled things so I can get the lengths right. I'll build the resevoir. The spinnable fittings are just to make my life easier, they're not absolutely necessary. But this should give me a full 2hp on 115v or 230v so I can change over in the future if I rebuild my shop. At 3000 psi which everything is rated for, it will generate 23.85 tons. I've changed components to be more focused on speed and it will move at over 2 inches per second in low pressure and 3/4" per second at high pressure. Pump is rated for motor speed. Motor is continuous duty with thermal overload. I've tried to pour over this shopping list to make sure this will do what I want and I don't think I'm missing anything. I'll probably pull the trigger today. ETA: lol I say that and notice looking at the post I need more 3/4 hose barbs for the return line. ETA2: I'm essentially duplicating a "25 ton" log splitter circuit that would typically come with a 5hp gas motor. Using the 2.5:1 gas to electric motor power rating ratio, a 2hp motor should be sufficient to give me the pressure the pump is capable of at the gpm it's capable of, with some slow down. If it's not, it's the weakest link in the system and I'll either adjust the pressure relief valve down to what the motor can sustain or, upgrade the motor and run wire for 230v to get into the 3hp range, but for me I think this is going to be sufficient.

mp2DHH9.jpg

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how are you sourcing your metal?
when i was doing research on presses i found the I or H beams to be a big part of the total cost

one of the other wip threads uses this valve i dont know if its any better than the one you posted but i thought i would post it here and let you know. I get the impression prince is just one of the good brands. Not really sure just posting options.
http://www.northerntool.com/shop/tools/product_37216_37216

really looking forward to your wip thread!!!
 
That's the easy part for me. Building stuff like this is what I do for a living :) Not shop equipment per se, but fabricated weldments.
 
Steel is easy to find, or at least I find it easy. I have a few very large steel suppliers within a couple miles of my office. I can buy anything they sell as long as I buy it at a min of 5' lengths. $1 per cut for any cut, from the smallest stock they sell to the largest beams they sell.
 
Depends if the press is a log splitter type or an H frame and if an H frame what kind of span you're covering.
 
lets say H frame 10 inch height clearance. and what would normal be 8 inches wide opening?
 
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