Medium Sized Hydraulic Press Build

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Aug 5, 2014
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Hey guys, so for quite some time I've been wanting to build a hydraulic forging press but have been especially stuck on one factor: size.

Currently the two options I've been oscillating back and forth between are 1) 20 Ton Bottle Jack Press (not so convinced due to requiring large air compressor and performance doesn't seem to be great) and 2) A full sized press inspired by eFleming's great press build WIP at this link http://www.bladeforums.com/forums/showthread.php/648250-WIP-Hydraulic-Press-Build

Due to size limitations, however, as well as wanting to be able to move if needed, I'd like to build something smaller than the full sized press that eFleming put together. Something in between those two presses would be great, something that stands, say, around 3 feet high total, that could be feasibly moved around if the need came up, would be perfect.

The main use would be for forging damascus and forging integrals from larger stock, so I'd like it to at least be capable of that. If I can get that and have it also be (moderately) medium-smaller sized that would be perfect!! I'm open to either the H style or C style press, whichever would be more practical and doable at a smaller size like that. FWIW, I like the design of the press in the photo below.

Any and all recommendations are majorly appreciated. Thanks as always for your help guys.

HB96WIll.jpg
 
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I would either change the hoses to metal clad, or put mesh sheathes over them. At a minimum. put a sheet metal shield that keeps them safe. A hot billet accidentally hitting a hose under pressure can be catastrophic.
 
Ok Karl good call, I think I still have some 4" casters I can use for that


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I like the design you posted too. I've got a shopping cart saved right now with everything I'll need but hoses to build one almost exactly like that, that should be 15 ton on a 20 amp 120v circuit. About $600 with shipping for the cylinder, valve, pump, motor, couplers, filter and breather. All I should need in addition is hoses which I will have made locally or run steel lines, which I want to decide as I build it.
 
Hey Kuraki sounds good maybe we can share some info/build tips to get a similar sized press if you're also going for the small to medium size. What size cylinder and motor hp are you going with?


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I'm just trying to stay within the capability of a typical 120v circuit, which is about 1.5 hp. I'm using a 1750 rpm 1.5 motor, a 4.5" bore cylinder, a 0.68 cubic inch pump. No load this should move relatively quickly, a little over 1" per second. At 2500 psi it will generate 19.8 tons in the push direction (15 was a guestimate earlier but running the numbers it's higher). A log splitter valve that's sprint return to open and adjustable relief valve, so a rocker foot pedal with linkage will be needed.

Motor is a farm duty 148T TEFC with thermal protection. Draws 13.8 amps. Can be wired 220 if I decide to go that route in the future.
 
If you use steel lines, do you have to include some sort of expansion flex fitting to reduce stress on the steel ?
 
If I use steel lines they will likely be terminated in short pigtails of rubber line to account for that. That's typically what I see on various other hydraulic equipment. But would keep the majority of the hose out of harms way.
 
That looks nice Nick. What size is that hydraulic unit?

Kukri - I would worry that 1.5HP would not deliver enough GPM under load to get much ram speed.
 
That looks nice Nick. What size is that hydraulic unit?

Kukri - I would worry that 1.5HP would not deliver enough GPM under load to get much ram speed.

Yeah. Now I'm seeing you can run a 2hp on a 120v circuit. I was thinking about the people running VFDs from an outlet maxing out at 1.5 hp but there's some efficiency loss there I suppose. They have the same motor style in 2hp for about $40 more.
 
That looks nice Nick. What size is that hydraulic unit?

Kukri - I would worry that 1.5HP would not deliver enough GPM under load to get much ram speed.

Hey Stacy surprisingly they don't list how many tons the red press is capable of but it does say they use a 3hp motor and 52" overall height. They have another model with two similar cylinders and 7.5hp motor capable of 50 tons so maybe the single cylinder is 25?

One other thing they list is that it weighs 800 Lbs [emoji33]if I could get the weight down to well under half of that (200-300lbs?) and cut down some of the height as well that would be awesome.

The 20 ton bottle jack presses that a lot of people have built seem so small and portable, compared to all of the automated presses that all seem to be pretty enormous. There's gotta be a middle ground right? [emoji6]

Maybe a useful question is - what is the minimum ideal press ton capacity for doing Damascus, integrals and forging from larger round stock? From there I could build out the frame to work with that minimum cylinder size and try to get it as small as possible while still being sturdy and safe.
 
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
 
Hey Stacy surprisingly they don't list how many tons the red press is capable of but it does say they use a 3hp motor and 52" overall height. They have another model with two similar cylinders and 7.5hp motor capable of 50 tons so maybe the single cylinder is 25?

One other thing they list is that it weighs 800 Lbs [emoji33]if I could get the weight down to well under half of that (200-300lbs?) and cut down some of the height as well that would be awesome.


Maybe a useful question is - what is the minimum ideal press ton capacity for doing Damascus, integrals and forging from larger round stock? From there I could build out the frame to work with that minimum cylinder size and try to get it as small as possible while still being sturdy and safe.

Dont' be on a hurry to put this on a diet

If you worry about moving it, split the power pack and the frame into two pieces, make the cylinder removable with quick detach fittings.


Just the Cylinder motor, pump, tank and oil will come to 200+ pounds

If you leave 100 pounds for the frame, you will just stretch the frame out of shape and square until it breaks.


The BAston Press book lists 24 tons as a minimum

However

Once you start doing damascus, it takes almost as long to do a small billet as a larger one that you may get 2 knives from.

A larger press my be more economical.
 
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.
 
We have a 24 ton press but I think Ive come to the conclusion that speed is more important than raw tonnage.Especially working Damascus which dosnt take that much power to work. that's just my opinion and not going against anything anyone has posted here so far...People think that 24 tons is small but it can easily punch the eye out of a 2" square chunk of 1045 hammer blank in less than three heats at only a high orange..Ive seen really fast 16 ton presses that do really big work because they have 10 hp unit and single phase pump...Fast! Only problem is they cost huge money to build like that..
 
I've never used one but I've seen a few bottle jack presses in videos and photos, the most notable being JT's video. To me they are like buying a 1x30 to grind knives. Will it work? Yes. Will you want to replace it with something better almost immediately? Yes unless you're really only making one knife a year. This of course is my opinion, but something that is often said when this comes up, usually by Stacy, is that if they were even half as effective as a real hydraulic press you would see a lot more people using them. I understand the weight concern but there is a point in knifemaking where one hast to decide "am I going to keep this simple and stay comfortable or am I going to go big and deal with the baggage that comes with it?". Mills, power hammers, surface grinders and a whole host of tools many knifemakers use are heavy and can't easily be transported or moved. I took the plunge and ultimately bought a forklift because I got tired of paying people to load tools. How deep down the rabbit hole are you going to go :D

On a side note, after a lot of reading I am in complete agreement with Kentucky (good to see you around btw). Tonnage is good but speed is better when it comes to a press. A guy named Larry Langdon wrote quite extensively on this in the press section of iforgeiron. I believe I posted this link in Kentucky's thread about forging presses last year. Its a good read.

-Clint
 
Could anyone tell me where I can get a switch like the one in Nick's OP? I'm not searching the right terms. I either find reversing rotary drum switches or dinky little 12v rotary switches. I'd rather not have a reversing switch but I guess it doesn't really matter.
 
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