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Bad 50 Ton Press Modification

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  • Bad 50 Ton Press Modification

    Well...I got a 30 ton homemade press from a fellow and after dragging it home figured it would be Perfect?for doing my Motorcycle Crankshafts for my Drag Bike. Well..I am amazed how much the steel frame will bend contort and twist when I get that 50 ton Cylinder going full force,, NOW im asking for some help as I need to build a press frame that can easilly withstand 50 tons of pressure, I ve alrready made up 3 inch thick plates to support the crank Bits,,, What size should the support Pins (Im gonna use 2 on each beam this time maybe ??one inch dia>??? and what size side and top beams shouls I be scavenging? My press was made from what I call 9 inch jumior beams (the type home builders seem to throw into the Yards and let lay around ,,that kind, anyhow I need some tips guys , I cant see doing precision type crank work with this abortion I currently Have in my new shop.. I am even thinking of a 4 post type press since all I wiash to do with it is Crankshafts (multi piece GS suazuki types )Thanx Guys Mike

  • #2
    sounds seriously underbuilt to me.
    a commercial 50 ton is gonna have at a minimum a 3"x 12" channel for the vertical, that would be a .280 wall, and weigh about 20 pounds a foot.
    None of my books list 9" junior beams- only 8" and 10", but an 8" junior beam is only 6.5 pounds per foot with a .135 flange thickness- so its probably about 1/3 the amount of metal it should be.
    Pins for a 50 ton should be at least 1 1/2", 2" is better.
    Cross frame at top, to hold cylinder, and across to hold the work, should be at least another 12" channel on each side. Bigger is better.

    50 tons is nothing to mess with.
    Unless you get a real engineer to do the calcs, I would suggest severe overbuilding is far better than underbuilding.

    Comment


    • #3
      Well here is a bright,shiney new Dake 50 ton press we got in for a customer,lot prettier than our old rag in the shop.



      They used 7" channel with a 3/8"web for the top,bed and side rails.The pins are 7/8",but 1"-4140ht would be better.The pins on our old Dake have been bent several times,dunno why

      It's a great press,but if I had to build it one thing I would change is eliminating the channel for the uprights.In it's place I would use four pieces of 3/4x4" flat.Easier to drill than the channel,allows for a bigger pin and leaves the sides open for shaft straightening.Kinda like this OTC press-

      http://www.google.com/products/catal...d=0CG0Q8wIwAA#
      I just need one more tool,just one!

      Comment


      • #4
        It seems to me that two pins would be just as good as four. If you intend for the table to be adjustable it would need some pretty precise hole locations to share the load between four pins. If only two pins are in contact, there is little point in having the other two.
        Don Young

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        • #5
          I built this press based on the then commercially available enerpac-
          its a whole lot herkier than that DAKE.
          Its a 30 ton model, and I sure wouldnt go smaller than this for 50 ton.
          Enerpac no longer makes this model, their current ones are made from flat bar, not channel.

          Comment


          • #6
            Originally posted by Ries
            I built this press based on the then commercially available enerpac-
            its a whole lot herkier than that DAKE.
            Its a 30 ton model, and I sure wouldnt go smaller than this for 50 ton.
            Enerpac no longer makes this model, their current ones are made from flat bar, not channel.
            It's morbidly obese No the old Dake in the shop is built lighter than that new one and it's a 1929 model.Been up past 55tons several times no problems at all.The only way I would go bigger than an 8" channel would be if I wanted a wider opening between columns.
            I just need one more tool,just one!

            Comment


            • #7
              50 tons = 100k pounds

              At 15,000 psi, that is about 7 square inches of tension part, split between the two sides..... I'd probably go with 1.3 x just because of off-center (normally the cylinder is right in middle though), so that's about 9 square inches of uprights cross-section.

              the Dake in Weird's pic has around 6+ sq in of tension area, when you take out for the pin holes. Close to my 7.

              1" pins x 2 would be about 3.14 sq in, for a shear of 32k per sq in, which is too high, so figure 4 x 1" pins, (or larger diameter pins, but those could take too much of a bite out of the channel). If the tolerances are not too loose, it will seat in and share with 50 tons load, it's 12.5 k lb per pin end.......

              The beam has no answer yet, because we don't know how wide you want the opening.
              1601

              Keep eye on ball.
              Hashim Khan

              Comment


              • #8
                Mine is 50T also, with a movable cylinder. I had to use 1-1/8 4440 for the pins to get a reasonable safety margin. Also check bearing strength, I had to add 1/2 " flat bar to the 12"x20# channel bed to get enough bearing area. Flat bar for the uprights is nice, but drill holes through the whole bar and you cut into your strength a lot, meaning you need bigger bar.

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                • #9
                  You might want to visit this website for some ideas. His press looks like it would do everything you want.

                  http://www.davepropst.com/Article/Art6/Article6.htm

                  Rick

                  Comment


                  • #10
                    My guess is that Dake specifically uses the small pins to provide a weak point so that you bend or break the pins before you twist the frame into a pretzel. Easier to buy or make new pins that straighten out the H frame.

                    I keep kicking around the idea of making a press, so I'm curious to see what everyones ideas are.

                    Also flat bar is nice too from a fabrication stand point as you can clamp or tack weld them all together and then drill all the holes in one shot so they all line up perfectly.
                    Mike
                    Central Ohio, USA

                    Comment


                    • #11
                      Do you really need 50 T to press those cranks???I press 2 cycle and single 4 strokes cranks with a 20 tonner and it does a fine job....Or is this a matter of bigger is better??? Shawn

                      Comment


                      • #12
                        Originally posted by shawnspeed
                        Do you really need 50 T to press those cranks???I press 2 cycle and single 4 strokes cranks with a 20 tonner and it does a fine job....Or is this a matter of bigger is better??? Shawn
                        Presses are funny,people buy or build them with the idea in mind"I'll only be pressing such and such no need for xxton press".

                        Then about two days later they run into something that the new press won't budge,or they quickly find other uses for the press.

                        50tons sounds like a lot,but from day to day experience over the past 20 years I have found a whole bunch of stuff it wouldn't push.
                        I just need one more tool,just one!

                        Comment


                        • #13
                          Lots of nice presses shown here and I didn't see a single shield in the form of chain curtain or rubber guards. The shop I started at did lots of heavy equipment work and there were several large presses about for pressing bearings and gears, all sorts of stuff. Every one of them had some form of protection from flying objects should something shatter. You shatter an axle shaft at 100 tons and the individual parts are like bullets.
                          James Kilroy

                          Comment


                          • #14
                            Originally posted by jkilroy
                            Lots of nice presses shown here and I didn't see a single shield in the form of chain curtain or rubber guards. The shop I started at did lots of heavy equipment work and there were several large presses about for pressing bearings and gears, all sorts of stuff. Every one of them had some form of protection from flying objects should something shatter. You shatter an axle shaft at 100 tons and the individual parts are like bullets.
                            And if you buy SOME types of press, and the asian maniacs supply a CAST IRON block with it....... I saw one "painted orange", with a cast iron block/platen/whatever you call it supplied. I know, because it had a chip out of it.....

                            I broke a CI platen on an arbor press once and pieces flew... I don't want to see it at 30 tons.
                            1601

                            Keep eye on ball.
                            Hashim Khan

                            Comment


                            • #15
                              Originally posted by jkilroy
                              Lots of nice presses shown here and I didn't see a single shield in the form of chain curtain or rubber guards. The shop I started at did lots of heavy equipment work and there were several large presses about for pressing bearings and gears, all sorts of stuff. Every one of them had some form of protection from flying objects should something shatter. You shatter an axle shaft at 100 tons and the individual parts are like bullets.
                              I ran some 300 ton presses in a die room and they all had one inch lexan all around. Even with that, if I had something that didn't budge after about 100 tons, I would stand beside it with the steel frame between the part and me.

                              The one inch lexan had cracks in it.

                              I am pretty sure that a 30.06 has nothing on the things that can fly out of even a 30 ton press.

                              Brian
                              OPEN EYES, OPEN EARS, OPEN MIND

                              THINK HARDER

                              BETTER TO HAVE TOOLS YOU DON'T NEED THAN TO NEED TOOLS YOU DON'T HAVE

                              MY NAME IS BRIAN AND I AM A TOOLOHOLIC

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