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Oops (crash)

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  • Oops (crash)

    Yes the title says it all. I was squaring up some 6061 blocks of aluminum today at work (i'm a 1st year apprentice). I was told by a couple of people that squaring up blocks with an angle plate is much easier and usually gets your blocks more square than a vice. Since i can never get a block 100% square in a vice, no matter what pattern i try (wether milling one face and flipping it to the back jaw, with or wihtout round stock, doing paralell faces first then flipping it... at best my sqaurness is always out a few thou although measurements with a vernier are always great), i decided to give the angle plate method a shot. So it was all going fine and i squared up some 3x3x11 and some 3x6x11 blocks but not the ends yet. I took light cuts, just cleaning up the faces.

    So i did my first 3x6 ends no problem. But the second one i did.. OPPS, as i touched off lightly, it cocked back in the angle plate, made a nice bang, stalled the cutter and put the head out a nice bit. Nothing broke though (that i know of) or flew out so that's good i guess. One guy started yelling saying 'thats why we don't square up with angle plates on mills, just grinders', and 'he's never seen it before', and another told me the problem was that the angle plate wasn't tall enough to support my block, and the C (or are they called F clamps? the ones that look like an F) clamps i was using weren't strong enough (they were wood ones that i was given to use, they didn't have a bar through the handle for leverage, but he uses them when he squares his blocks). I'm tending to agree with the second guy becuase i don't see why you can't use an angle plate to square up a block on a mill. But mind you too this was an aluminum block not a steel block... can you still square up a steel block like this too? Or should the whole angle plate on a mill thing be avoided all together and just use a vice?

    [This message has been edited by Derek13 (edited 12-07-2004).]

  • #2
    Tighten it up? It's slipping?


    • #3
      My .02. I use a vice for squaring. I find using an angle plate for that type of work cumbersome and troublesome. I rarely use angle plates at all. The last job that I did, last week, that required squaring aluminum blocks, were 2.940x3.365x5.030, a bit smaller than what you were doing, all done in a vice. If you are going to "square up" using an angle plate, use one that is ground, (before I get blasted for mentioning it, note that a ground angle plate is "intended" for layout and inspection work rather than machine work), as heavy as possible, thick flanges, ribbed for reinforcement, and, at least as high as the work. If you are going to clamp to the face of the angle plate, use heavy "C" clamps, as you were told the "F" clamp will not hold securely enough. The angle plate itself will affect the squareness of your work. Are you using a machined or ground angle plate? As you would guess the ground angle plate is a lot closer to "square" than a machined one. If the angle is not square within the tolerances you require, without shimming and fiddling around with it, keeping square will be trouble. The work will be a direct reflection of how square the angle plate is, and/or how square the angle plate and work are to the machine table. The condition of the machine and how well/carefully the set up is done will have some affect also.

      [This message has been edited by ERBenoit (edited 12-08-2004).]
      Paying Attention Is Not That Expensive.


      • #4
        Your vise may be out of square and need a shim, or skim grind job on the master jaw.
        Could there be crud under the vise?

        Indicate the solid jaw of the vise, up and down with an indicator held in the spindle (after tramming the head)...

        Do this test with a block clamped in the vise similar to your job.

        If the spindle tends to rotate, raise and lower the knee.

        If that checks, and the knee is square, you should be good to go.



        • #5
          I'd have to go with the wooden clamp. Don't know why it was suggested to use them, maybe someone F**kin with you?

          I use kant twist clamps, they make a deep throat type also. I couldn't shift it with a hammer (not friggin wailin though) once cinched down. JRouche
          My old yahoo group. Bridgeport Mill Group


          • #6
            WE only use angle plates to hold material in place for angular machining on the mill in cojunction with a sine bar. We use angle plates or two of them on the surface grinders for datum grinding blocks and for grinding angular faces. We use bessy type clamps to hold them on and tighten the crap out of them within reason of course, PS Listen to the old guys or read a book on machine work. There are a lot of I know it alls in every Machine shop who really dont know much. Madman