Some things to consider when using a shop press

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • wierdscience
    Senior Member
    • Jan 2003
    • 22085

    Some things to consider when using a shop press

    With the recent article on building a shop press I thought I would share some advice on using them safely.

    While most of you maybe experienced with their use,others may not be.

    A press of 50 or for that matter even 20 tons can develope significant explosive force,50tons doesn't sound like much,but considering that it is 100,000 pounds it is considerable so certain safty habits should be learned in their use.

    Since one of the most common uses for a press is to remove and install bearings and races,having witnessed several accidents and having shrapnel removed by a doctor myself I learned to first measure everything before pressing,the wrong bearing can ruin your day,do not go by the bearing numbers because on specials and automotive units many times the numbers will be the same as the common bearing in the catalog,but be mfgd to a defferent spec,this cost an old friend his life,he was pressing a bearing on in a 60ton machine when the bearing exploded and a piece of shrapnel went through his heart and killed him.He broke two rules#1 he trusted the parts counter #2he didn't use a shield.Evere since then I will either wrap the shaft in a leather apron or if I must see the part I will use a plexi sheild.

    The next common use is for staightening or bending shafts or stock.If you use vee blocks for this be absolutely sure that they are made from steel and not cast or malleable iron,they to will part company and ruin your day.Also make sure that the blocks and the surface they are resting on is free from oil,you don't want any slippage.When straightening serverly bent shafts always use a pair of stabilizer forks(rods attached to the press table to catch the shaft incase it should roll and pop out)I was once pressing a bend out of a large(150lb) hydrualic ram,it was a large open sided press and I had the habit of standing behind the press frame(plenty of steel between me and the part)but the customer was watching me and walked in front of the press with the part under load,I told mhim to move out of the way in case it should slip and just as he cleared the side of the press it popped out and hit the shop wall 30' away.

    Always avoid using long push bars and if possible they should have a means of being attached to the ram,I have found that a couple of sets of cheap impact sockets both shallow and deep make good press tools,they are soft enough not to shatter,but tough enough not to deform,plus they come in a range of different size od's.I never use things like automotive wrist pins(my own piece of shrapnel)or things like valve stems and the like.

    To many of you this maybe old hat others maybe not,I don't mean to preach,but I hate to see people's lives interuppted by an unforseen danger,my buddy had a wife and two kids and lots of bills,but left them alone in an instant,it could have been avoided.I hope if I missed anything you guy's will add unto.

    [This message has been edited by wierdscience (edited 06-18-2004).]
    I just need one more tool,just one!
  • crews1
    Junior Member
    • Nov 2003
    • 27

    #2
    Good post. Too many times in the hurry-up, "dollar-a-minute" enviroment, shortcuts are taken that just aren't worth the risk.

    Comment

    • j king
      Senior Member
      • Apr 2003
      • 909

      #3
      Weird..Good advice.A trick I use at work is to wrap a length of chain over a shaft or bar.
      As you said about straighting shafts,if they are bent bad just lay the chain a few times as a blanket on the shaft.If it kicks out the chain keeps it from flying.
      Most of the pieces I have seen fly were hardened shafts that break when trying to straighten them.Makes you go to the boys room and check your shorts.

      Comment

      • ibewgypsie
        Senior Member
        • Dec 2002
        • 5724

        #4
        The progressive die presses at one place I worked, They hit bang bang bang continuosly for hours at a time. I'd stand mesmerized by them, A band of metal coming in, parts going out, cut out and shaped perfectly.

        A small screw got on the die (from who knowes where) came out like a peach-pit probably a couple hundred miles a hour and stuck in the wall.

        Just cause it is safe one moment does not mean it will be the next.

        (my modified shop press is almost up) I like my fingers, eyes, and life just the way it is. When a hose gives way, it can inject fluid under the skin, where it has to be cored out like a apple. Not a good thought. Cylinders like objects being pressed can shatter.

        The gadget I built my special purpose press for is automated, something else to play with, hopefully make me a dollar and not get me hurt. A expensive investment that I hope will repay for itself.

        David

        Comment

        • Excitable Boy
          Senior Member
          • Nov 2003
          • 253

          #5
          Timely post as I've been looking for a small H frame press to use my broach cutters with.

          Thanks,

          John

          ------------------
          Pursue Excellence and the rest will follow.
          Pursue Excellence and the rest will follow.

          Comment

          • abn
            Senior Member
            • Feb 2002
            • 783

            #6
            Thanks for the post...I've been using old wrist pins for press work. Looks like I have a habit to change. My press is the el cheapo Harbor Freight 12 ton...I worry about the press exploding more than the parts or tools

            Comment

            • Happy
              Senior Member
              • Mar 2004
              • 135

              #7
              anyone have a picture of a good plexi shield?

              Comment

              • Evan
                Senior Member
                • May 2003
                • 41977

                #8
                Buy some 1/4" Lexan, not plexiglass. Lexan will stop a bullet.
                Free software for calculating bolt circles and similar: Click Here

                Comment

                • lynnl
                  Senior Member
                  • Jan 2002
                  • 7181

                  #9
                  Thanks Weird. It'll probably never be known but you may well have helped someone like me avoid a tragedy. I don't have a press (yet), but I have zero experience with them, and was not really aware of the potential hazards.
                  Lynn (Huntsville, AL)

                  Comment

                  Working...
                  X