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Thunder

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Posts posted by Thunder

  1. reinforcing couldn't hurt, I think on my first press I busted 1/2" bolts.... and as stated above don't squash steel unless its hot, hot steel squishes easy, cold steel stresses the frame. My original press is still being used. 1/4" is good on the square tubing, and do not know if bolts alone will do the job. Be careful its small but it is still 20 tons.

  2. As to the questions on the air compressor ... I use a very
    old 3 hp 120 psi max compressor. The pressure never seems to get up to 120, but
    stays around 100. It works fine, but a larger compressor would be much better.
    HF 20 ton recommends no more than 120 psi. Sorry for the long delay in
    answering questions, I need to check to see if I am getting email updates. Your
    ingenuity in the various press designs are amazing.



  3. I've been looking at this thread for over almost 2years. I finally have the jack and a lot of steel but I dunno about my welding. Only because I'm only using a little mig. I have the Hobart Handler 140. I havent had any of my welds fail(YET), I've welded things that are way thicker than it's rated for, but i chamfer the pieces and go slow and make multiple passes. What do you guys think that are using full power welders? Should I attempt this or should i find another welder? I worry about hiring out the job since I really want it perfectly square and plumb. I personally trust my welds with this little welder but I've never had the torture test of a 20 ton ram on them.

    I am not sure if a Mig will hold it or not. I have always stick welded. You could tack it all up square and then have it stick welded, or mig it - and be very very careful until you are sure they will hold.

  4. look over these videos they may help answer your questions;

     

    youtube mini press

     

    Failures will depend on how good your welds are, your design, and materials.

    I do not recommend pressing on room temperature steel, only press on steel that is at forging temp

    Hot steel is softer than cold steel and mashes easier.

     

    20 tons is 20 tons, it doesn’t matter if it’s a 6 foot tall press or a 2 foot tall press,

    However keep your die sizes small, as that 20 tons is spread over large dies

    Large dies will reduce its pressure by the surface area of the dies.

    Always inspect your press for deformation of the uprights, and horizontal bars,

    I expect deformation and I am always watching for it to occur. When I see evidence of it, I beef up that area.

    I hope this helps these presses as everything we do in forging is very dangerous – keep this in mind.

  5. Seth - The pressing area of the dies determines the pressure exerted. My dies are 2” wide that gives a good amount of force, however if your dies are 4” across then you get about ½ the amount of pressure.

    The air motor has a discharge port where one would feel air escaping. Air shouldn’t be leaking from other areas. Remember this is a hobby press, it’s not going to have the force of one of the $4,000 monsters.

  6. Excellent walkthrough ... i have just one question... whats that silvery module sitting on the jack ? where the tube goes in ?

     

    -vids-

     

    Vihalvor

    It is a H.F. Air over Hydraulic jack. It is not a conversion; the silver module is the air motor that runs the jack. HF number - 95553.

    here is a link to see the jack: 20 Ton Air/Over Hydraulic Jack

    Looks like you have a good start on your press.

    Hope this helps answer the question.

     

    T. A. toler

  7. I know nobody's posted in here in a while, but I just found it and had a quick question. I know somebody mentioned that they were gonna try a regular non-air compressor jack, but never saw anything about it afterwards. The reason I'm askin is that I've got an air compressor, but it only gets up to about 100 psi on a good day, and buying another one plus the jack really isn't an option right now :( I know it would be a little bit slower and more work than one with an air compressor, but it sure beats the heck out of doin by hand :blink:

    Thanks for postin so many great designs ya'll, definintly got me thinkin

     

    Chris

     

    I haven't seen a mechanical version of the press.

    But if you can make it work we would love to see one.

    T. A. Toler

  8. Eastvillage - 1" bolt is good, couldn’t tell from the graphic, not sure what mine are, I broke the first set and went to a large set, mine are on the ram bar, my top member is welded.

     

     

    NESM - good idea, bottom member is just there to reduce the frame depth, bottom member is two 1" X 2" solid bars welded together, plenty strong.

     

    blacklionforge - go for it, I've thought about that experiment myself, if you can make it work that would be very cool indeed.

     

    Casey -

    The only way to know is to experiment. There are a lot of variables in these presses, maximum air pressure, frame flex, etc. I think my current flattening dies are about 3” X 4”, I have a couple of variations. One set has a depth limiter so I can get a pretty perfect 1/4" thickness, it is 2" deep. I very rarely squash anything wider than 1 1/2".

    Pressure is the ratio of force to the surface area over which it is exerted. If you tried to press the full with and depth of 3 X 4 then it’s going to be a struggle.

     

    Hope I got everyones questions answered and didnt miss anyone.

    T. A. Toler

  9. Eastvillage, reefera4m

    Very nice jacks, very clean machines. One note: Watch the bolts and pins. If they start bending or deforming you may have to go with a thicker diameter, maybe not, just keep an eye on them, occasionally pull them out and inspect them for cracks etc. I had some bending on the first bolts I used and moved up to a larger diameter. Safety first, both of your machines look very well done.

    T. A. Toler

  10. hello all I have been watching this thread and i been wanting to make a press, Has anyone had any problems useing thin wall squre tubeing? Thanks you for your time.

     

    In my original press, I made it entirely out of scrap square tubing lying around my shop.

    There are at least two different wall thickness, neither of which are 1/4. I would recommend that you use 1/4” , from a safety minded point of view. Much stronger frame.

    T. A. Toler

  11. I bought a 20 and 30 ton jack, the 30 ton jack is about half as fast as the 20 ton version. I'm going to build two presses and see how I can use both in different operations.

     

    20 tons is the compromise between power and speed,

    the more tonnage the less speed.

     

    T. A. Toler

  12. I love this thread! Great contribution one and all!

     

    I'm about to build one of these 'mini presses' but am curious about one aspect of the most common design. Why is the base typically constructed of short sections of square tubing? This seems an unnecessary expense. Wouldn't just using a 1/2' thick plate for the base work (or even 5/8" or 3/4")? Especially since most presses also seem to have plates on top or bottom or both. If bracing the uprights is a concern, wouldn't a few simple gusset braces work? I would think that this would also cut down on the weight and make the press more portable. If the concern is to keep the base from twisting or bending, adding a couple of stiffeners should be less expensive.

     

    Again, just curiuos.

     

    reefera4m

    The original press was made from scrap that I had lying around my shop, that scrap happened to be 2” square tubing. You cannot tell from the graphics, but all of the tubing wasn’t even all the same wall thickness. The beauty of this press is what I presented and offered to the group was a concept; ever one that has made this press has added or subtracted their own ideas. Every press is just a little different, everyone trying their ideas and then presenting the ideas to the group and making the concept not mine but ours.

     

    Try your ideas and then let us all know what you found out. Just remember - its little, but it still exerts 20 tons of pressure on the frame and components. Twenty tons is enough power to hurt you - really quick. I always make test runs on a new press before I get my face and body in harm’s way. Test the press then check your welds and determine if your bracing is deforming or moving off center. A bad weld or a frame that is not square will fail. I suggest stick welding; I don’t trust mig or wire welders they just do not seem to penetrate deep enough. Your experience may be different.

     

    Good luck and tell us what you find.

     

    T. A. Toler

  13. I've read this thread 3 times now and decided this is definitly a piece of equipment I need. It will solve a lot of problems that I have with building a big press.

     

    I found a company in the Netherlands that sells the 20 ton jack, they also sell the 30 ton variant with springs. I was wondering if anyone tried this type? I question the downward movement will be fast enough.

     

    potkrik.jpg

     

    This jack looks very similar to the motors we are using here in the USA, if it is fast enough or not - all depends on your expectations. It is after all - a mini hydraulic jack - it has limitations as compared to the full sized presses and it has advantages.

  14. I've been looking at the manual for the HF 30ton, and with the diagram they give it would be feasible. I'm just not sure what sort of pressure these work at. Any idea what the cylinder bore is on that 25ton? If I knew the piston bore I can extrapolate working pressure from load rating. If its 4000psi or less I might be able to try this conversion.

     

    Try one of these, I havent read them yet

    20 ton air/Hyd.

    http://www.harborfreight.com/manuals/95000-95999/95553.pdf

     

    manual jack - all

    http://www.harborfreight.com/manuals/66000-66999/66450.pdf

     

    TA Toler

  15. Just out of curiosity, has anyone tried removing the pneumatic assembly on these jacks and tried direct driving the thing as though it were just a single-acting hydraulic cylinder? I'm considering this, but I can't find any information regarding the jacks operating pressure and plunger size.

     

    I haven’t.

    I cant remember anyone posting how to achieve this conversion.

    But if you can figure out how to do it,

    I am sure we would all love to see it done.

     

    I will look when I get home tonight and see if I have any information on pressure etc, it may be on the instructions that came with the jack.

     

    TA TOLER

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