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  • zero in vice on mill tabel

    Does anyone have as much trouble squaring a mill vice on the mill table as I do?? What is the secret? I used a dial indicator and it was all over the place. I quit after an hour of frustration..I have a lugan knee mill and I need a simple way to square the vice..It'a a kurt vice.
    jmson

  • #2
    here is how I do it..

    I start by putting a 24" ruler in the vice (lightly) and eye ball the ruler to the table and snug the bolt on the left half assed tight.

    that gets me to within .005- .010.

    then I indidicate it closer and tighten the left bolt more.

    I zero the dial and run it left to right and tap out half the error with a dead shot.

    about 3 trips back and forth and tighten both bolts more and more(carefull not to move it).when the dial stays at zero it is done.

    With more practice you will be able to do it in about 5 minutes or less.

    good luck

    [This message has been edited by tattoomike68 (edited 03-03-2005).]

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    • #3
      Here's how I do it...I'm sure others will have better ideas.

      My vise is on a swivel mount, but the same can be done with mounting directly to the table. I snug up the bolts bolts on the swivel base, and run the indicator across the fixed jaw (indicator mounted in spindle). If I have .020" travel on the indicator, I tap the side of the vise a bit with a rubber mallet until the needle moves .010 in the right direction, and then tighten down the bolts while watching the indicator to be sure it doesn't move while tightening. I usually progressively tighten one bolt then the other until I'm clamped down.
      Arbo & Thor (The Junkyard Dog)

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      • #4
        On our old vertical mill I used to have to put 6 - 6in Kurt vices in a row. They not only had to be parallel to the travel but also in line with each other.
        I would snug (not tight) the left hold down. Put the indicator on the left side back jaw. move the table to bring the indicator across the jaw. Tap the right side in or out to bring it to the same indicator zero. Snug down.Run it back to the left and confirm zero, on to the next five with the same zero on the indicator always double checking the indicator zero once tightend, with the previous vice.
        Got so I could set the six in less than half an hour. Of course about that time the boss would stick his head out and say " before you put those vices on I got one more......"

        Matt

        BTW
        I have no affiliation with Kurt Manufacturing.

        [This message has been edited by Sprague M (edited 03-03-2005).]
        Matt

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        • #5
          Arbo. I do it like you do, but I first push the vice firmly up against the hold down bolts and just snug down the nuts. I then proceed as you do. Once I have it dialed in I tighten the hold downs and check alignment one more time. Takes two, three minutes tops. My thumper is an ancient piece of copper bar.
          I never true the vise using the swivel. It seems to take longer and there is a tendancy to over compensate. So I just return the swivel to zero and proceed as above.

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          • #6
            I just did this and used a dial indicator on the mill's spindle and set it against the rear jaw.

            One thing, I tightened the right bolt snug and then used a plastic hammer to move the vise.

            Remember that the bolt that is snug is the approximate point of rotation when you tap the vise. That point is to the right of the jaw. So when the left side is .010" different than the right jaw, just splitting the difference will not get you lined up. You need to factor the position of the snug bolt into the equation, too!

            Draw it out on paper and you will see that rotating the vise about the right bolt moves the left side of the rear jaw more than the right side.

            That effect might be what is frustrating you. You just need to take into account where the pivot point is relative to the two points you are measuring.

            I torqued my bolts down in stages, tightening each a little in turn to prevent the vise from shifting. A final check confirms if you got it right.

            Marv

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            • #7
              Some of the best money I have ever spent was for the factory Kurt keys that match the underside of the Kurt vise to my mills. Throw them on, bolt them down and they are usually within .002". If I need better, I can "tap-them-in", but with the keys it's a lot easier. BTW, I made my first set and the result wasn't as good as "off-the-shelf" from Kurt.

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              • #8
                Hi jrmason,
                You state your vise is a Kurt make, well if it is a Kurt it will have what every well built vise has, that is "T" slot and 2 short keys, held in place by an allen head cap screw. My wilton vise is a copy of the Kurt and has this "T" slot with the two keys.
                You don't state wheather your vise has the optional swivel base, It doesn't realy matter as both the swivel base and the vise have their own "T" slots.
                The "T" slot is built into the swivel base and vise for one specific reason, which is to automatically position the vise on the table to the exact orientation that it was set to the last time they were mounted on the table , with in a few thou, depending how loose the key were in the table.

                When my Wilton arrive I noticed the Keys were wider than the "T" slots in the table, rather than cut down the new keys on the vise, I removed them, and then made new step keys that fit the vise on one end, the bottom half of the key to fit mt 16m/m wide "T" slots of my milling table. Once installed, the bottom of the vise was cleaned as well as the table was checked for any stray chips or dirt. Then the vise with base was set on the table and the keys dropped in the "T' slots of the table.

                I was taught to push the vise towards the colunm, so as to force the keys to one side of the "T" slot of the table, then tighten the base nuts. This procedure is the same for just the vise alone too. But now to test or set the vise jaws parallel to the table travel, there are some items to check and adjust for parallel to table travel.

                Once the vise with mounted keys is bolted to the table, a check must be done on the loosness of the table gib loosness, to check gib movement the knee and saddle locks must be applied, leaving table as the "only" movable part of the machine, failing to lock the knee and or saddle will cause confussion as to where the actual movement is comming from.To check for excess play in the table gib fix mag bass dial indicator to colunm of machine, set dial indicator onto table's side closest to colunm but as far away from the colunm as the mag base allows. Traverse the table back and forth in it's travel noting any indicator movement 90آ° from parallel travel(does the table wander,move towards the colunm or away from colunm), if so the gib must be adjusted to remove this play without the table binding throughout it's travel, adjust gib and retest. One a used machine there will be wear in the middle of the table's travel, what you are aiming for is have a little resistance of the table crank or hand wheel at the end of table travel.
                If your table is still too loose in the middle of its travel, you can lightly apply the table locks to remove side ways slop or play.
                OK, with the table gib adjusted, the knee and saddle locks applied, mount mag base on the overarm or ram of the mill do not mount on spindle the spindle can have play in the drive, as well as it's bearings, mounting a mag base to the spindle will introduce any or all spindle play.
                With mag base on the overhead ram, open up vise to max opening, position dial indicator tip on fixed face of vise, zero dial, traverse table noting any dial arm movement.

                If this test is on a vise with a swivel plate, loosen the two "vise to swivle plate" bolts, but leave bolts a snug a little, traverse table to run dial tip from edge to edge of vise jaw, tap the wrench end of vise to correct, or so there is no movement of dial arm ("0")indicator reading, once "0" tighten vise to base nuts ,test again.

                For just the vise mounted to the table, mount the mag base and dial indicator as above, traverse table as above note dial reading, NOW, your vise is keyed and bolted to the table, there are only two ways to properly to adjust your vise, the quick and problem way, remove one of the keys of the vise file of grind the key to have vise jaw parallel to table travel
                The correct way, is first, if your vise jaw is not parallel with the table, that can only mean that the key way on the bottom of the visw is not parallel with the vise jaw, to correct, the vise must have the key way corrected via milling and the making custom keys, That way, by keeping the keys snug in the table "T" slots you are guaranteed near perfect vise jaw alignment with the travel of the table,with in a couple of thou. "every time" you install your vise. You just remember to just push the vise towards the colunm before tightening the nuts, this last step will bring the fixed face with in .001", of parallel to table travel.

                One note if your vise has steped keys, they should be checked first to be sure that the step is centred to the uncut portion of the key, this to be done first, before the above

                ------------------
                Doug
                Doug

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                • #9
                  You are dial indicatoring agains the fix jaw?
                  David

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                  • #10
                    <font face="Verdana, Arial" size="2">Originally posted by David/toledo:
                    You are dial indicatoring agains the fix jaw?
                    David
                    </font>

                    Yes. The fixed jaw is your refrence.

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                    • #11
                      I think everyone else pretty much covered squaring your vise whether you use the step keys or not. Personally I don't like the step keys, I indicate my vises within .0002 to .0003 or better sometimes, and this takes less than a few minutes. When you get good at it you will look back and laugh at how much trouble it gave you. One other thing I would add to all this is to stone both your table and vise bottom each time. I keep a good stone in a coffee can filled with half kerosene and half motor oil, just enough to cover the stone. You don't need to get overly aggresive with the stone, just rub it on the table and vise bottom. It will only cut the dings that may happened when moving the vise or working on the table. You will be suprised what you find if you haven't done it before. After stoning I clean the table and vise with acetone and a clean rag. I take my vise on and off enough at work that I don't worry about it rusting underneith, but if you plan on leaving the vise on for long time rub a little oil on the bottom before you put it down to prevent rusting. Good luck now go make some chips.

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                      • #12
                        Okay,here it goes one more time.

                        Table keys,first measure the width of the table slots to within .0005"

                        Next,machine up some new keys to fit the vise slots tight(tap in with a hammer tight)and 1/16" or so wider than the table slot on the opposite side.

                        Bolt a section of square bar or square tube approximately 1-1/2" square and 8" long.

                        Mill both sides of the block true for the full length.

                        Turn the vise upside down and clamp the vise to the block.

                        Mill the table keys to the table slot size+.001" and taper file them from bottom to top so the bottom of the key is -.001" and the top +.001" after they are tapped in and bolted to the vise.

                        Now when you set the vise and tighten it down it will be perfect everytime.

                        If it is a swivel base vise,set the degree scale to zero before fitting the keys and drill and ream the base and vise for a taper pin.Doing this will allow you to swivel the vise and return it to zero everytime.

                        [This message has been edited by wierdscience (edited 03-03-2005).]
                        I just need one more tool,just one!

                        Comment


                        • #13
                          Kurt type vises have an advantage over rounded Bridgeport style vises,in that, you can rough square them parallel to the column in seconds. All you need is a piece of ground O-1 stock or any other kind of known straightedge/parallel that is at least 8"s longandabout 3.5" -4"s wide. Place your vise on the table, snug up you bolts, then run the tables 'Y'axis in to the column while holding the piece of flat stock between the vises' back jaw and the columns' ground ways. Snug up the bolts some more then run your indicator along the jaw. Unless things are really out of square on your vise, you should be within .002 or better. Indicate to zero by tapping it in and carefully tighten your bolts so as not to tourque the vise out of line. You can use the same method to set the vise up at a right angle to the column using a large machinists square in place of the parallel stock. Quick and easy, no fuss no muss and no keys to worry about.

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                          • #14
                            it is called practice,practice practice. the shop i work in and my own we have no keys. and we get it done in less then 5 min. the same if we are setting up the jig bore.

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                            • #15
                              And once setup properly it's, push towards column, and tighten the nuts. Time: 20 seconds!

                              ------------------
                              Doug
                              Doug

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