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jrmason
03-03-2005, 02:06 PM
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.

tattoomike68
03-03-2005, 02:18 PM
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 http://bbs.homeshopmachinist.net//smile.gif

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

Arbo
03-03-2005, 02:21 PM
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.

Sprague M
03-03-2005, 02:57 PM
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).]

Rustybolt
03-03-2005, 03:07 PM
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.

debequem
03-03-2005, 03:27 PM
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

Jim Caudill
03-03-2005, 04:03 PM
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.

vmil3
03-03-2005, 06:10 PM
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 90° 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

David/toledo
03-03-2005, 07:29 PM
You are dial indicatoring agains the fix jaw?
David

Rustybolt
03-03-2005, 08:47 PM
<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.

mochinist
03-03-2005, 08:55 PM
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.

wierdscience
03-03-2005, 10:17 PM
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).]

ARFF79
03-04-2005, 02:41 AM
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.

bob308
03-04-2005, 07:22 AM
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.

vmil3
03-04-2005, 12:58 PM
And once setup properly it's, push towards column, and tighten the nuts. Time: 20 seconds!

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

Dr. Rob
03-04-2005, 03:53 PM
Another one: Just take a skimming cut across the face of the fixed jaw. Done. Zero runout. And gives you a zero for tool settings.

No kidding. Started making my own vise jaws a while back. What a great thing. They're usually just a piece of flat bar with screw holes. If you make your own you can mill fixtures and stops for repeating jobs, or contours for odd-shaped pieces. Easy. And in that case, you might as well just take a cut across the face to guarantee square & truth.

Another one:

Bolt a pair of small, unobtrusive blocks or cylinders to the table, one at each far corner. Take a small guaranteed-to-be-square cut off those. Good, now leave them there forever. If you want to use the vise, put a long straight bar of anything in the vise jaws. Push it up against your blocks and clamp to table. Done. Might be off by x nths of a thou, but across the length of the table it becomes a very small error indeed.

laddy
03-04-2005, 06:25 PM
Hey,
I am a nebie so take that into consideration. I bought the mini laser center/edgefinder and WoW!!! I think it will make my life a considerable amount easier. I am not well versed in the use of the indicator and usually give up shortly after trying. For me I think it will be a great help. Fred

krazyglue
03-04-2005, 10:18 PM
Is the fixed jaw flat?

If the jaw is bowed you can run an indicator across it all day it wont be true.

Yes this has happened to me lol

Dont worry once you get your own system it will take you less than 5 minutes to square up the vise. Once you get good at it you dont flinch at breaking your machine down.

wierdscience
03-04-2005, 10:37 PM
Why does everybody shy from table keys?

Once you fit them it's done,over,fin,fineto.

No,squares,no slop,no indicators,just a wrench and two bolts,that's it.

Neat thing is,the vise CANNOT slip out of square,ever!

B-ports are bad enough with going out of tram,why add to the problem with a vise that runs off?

bob308
03-04-2005, 10:54 PM
the problem with keys is you can not set the vise at an angle. also if you have a job too big for a vise do you put keys in it first? indicating a vise is the first thing to learn. then you have to learn to tram in a round part. then how to find center with an indicator.

wierdscience
03-04-2005, 11:58 PM
<font face="Verdana, Arial" size="2">Originally posted by bob308:
the problem with keys is you can not set the vise at an angle. also if you have a job too big for a vise do you put keys in it first? indicating a vise is the first thing to learn. then you have to learn to tram in a round part. then how to find center with an indicator.</font>

Angle setting?That's why they make swivel bases.
No,but for these jobs the vise is removed anyway.
Indicating a workpiece should be learned,so should properly fitting table keys to a vise,but indicating the vise everytime it is removed and installed is a waste of time,wasting time is not a marketable skill(unless you work for the government)

Finally,use reverse logic,if you wanted to indicate a part that's clamped to the table with no registers every time you use the mill.....then why have a vise at all?

Not riding you,but after indicating everything under the sun for the last 15 odd years,I use table keys more than indicators.

Derek13
03-05-2005, 12:03 AM
There's a couple diff ways i learned through progression... basically throw the vice on, aline it roughly with a square... clamp something in the vice like 123 blocks.. tighting the RIGHt side of the vice (not totally but almost) and just barely snug the left side... start 0 at the right side of the vice move to left... now you can either try to hit half the difference, OR waht i do now is move the table slowly and just tap the vice int he opposite direction of indicator travel untill you see the incidator not moving. Then run the indicator back to the left and amke sure it reads 0/0... then fine tune accordingly... this can be done by just simply tightening one vice clamp a little more.

once you learn how to tap the vice to ALMMOST alined while moving the table, indicating is a breeze. Helps with indicating blocks on angles aswell!

[This message has been edited by Derek13 (edited 03-04-2005).]

[This message has been edited by Derek13 (edited 03-04-2005).]

ARFF79
03-05-2005, 03:04 AM
Wierd, Keys are great if you are only using the vise in one direction and on the same machine. Granted in a home shop environment multiple vises being used on several different machines is not likely, but there are always exceptions. I currently own 5 mills, all with varying T slot widths. Going from a single vise to a multiple vise set up on any one mill would require changing keys. Add to this different vise manufactuers and you end up with a nightmare of possibilities in mixed up keys. If you learn how to do it without relying on keys, then, it will not matter if you have them or not. The issue of commonality and standarization make set ups go faster, but unless you are a fairly good sized business, you will find a mixed bag of work holding devices. I have yet to work in a place that got rid of anything that was not broken beyond repair or use. One small shop I was in for 2 months used an old wood working vise because the owners father used to use it in the 30's, so it held that it could still be used in the 70's right along side thte 1885 punch press that scared the begebers out of me every time I ran it. They threw out nothing and the back room looked it.

wierdscience
03-05-2005, 09:43 AM
Did I say keys always have to be used?No,they do not,but if you have one,two or ten vises that get used on the same machine over and over it is stupid to keep indicating in the same vise everytime.

So,just go out and make things complete.Take all your lathe chucks off and face the registers off.That way you can swap chucks between lathes,all you have to do from then on is indicate them in,right? http://bbs.homeshopmachinist.net//biggrin.gif

mochinist
03-05-2005, 11:31 AM
Stupid is assuming what works best for you is the best way for everyone else. Use the key if you want, I dont like them I prefer to see that the vice is square by indicating it. I bet I can put on a vise, indicate it, know that it is squarer than yours, and it would only take a min or two longer. I would hardly call that wasting time, more like part of the job.

cpm10v
03-05-2005, 11:55 AM
I too don't like the keys that come provided with some of the Kurt vises. Nice idea but I like to "know" that the vise is zeroed-out. The keys don't repeat well enough for me. Just as a rule of thumb going through apprenticeship I had always been told that before you start a job of material importance, always indicate the vise in, no question, and check it again after you've done heavy milling. To each his own, but I've found the keys don't give me enough piece of mind to rely on.
Greg

wierdscience
03-05-2005, 08:00 PM
<font face="Verdana, Arial" size="2">Originally posted by mochinist:
Stupid is assuming what works best for you is the best way for everyone else. Use the key if you want, I dont like them I prefer to see that the vice is square by indicating it. I bet I can put on a vise, indicate it, know that it is squarer than yours, and it would only take a min or two longer. I would hardly call that wasting time, more like part of the job.</font>

There are methods that work without fail and those that work most of the time.
Once the keys are fitted and milled true to the travel of the machine the vise jaw will indicate in to the accuracy of the chuck jaw period.There is no guess work and no chance of it slipping.

Fitting and truing vise keys IS part of the job,if you want to cut corners that's fine with me,just don't do it on my dollar.

mochinist
03-06-2005, 04:52 PM
Don't worry weird, I make it a point not to work for a-holes that think they know everything.

Dave Opincarne
03-06-2005, 05:30 PM
Hate to do it http://bbs.homeshopmachinist.net//wink.gif but I gotta side with the weird one. There's nothing in the use of keys to preclude checking the face with an indicator or to prevent the use of a swivel base. No one's holding a gun to your head but in a job shop where time is money spending time to dial in a vice when you don't have to doesn't make sense. If you're looking for greater accuracy than the keys can provide then you should be using a surface grinder not a mill.

mochinist
03-06-2005, 08:21 PM
Ok whatever use the keys I just said I don't like them. I can put on a vice in a small amount of time my way. My boss seems to be happy with my times, I got a raise last week and have bonused every six months for the past five years. Guess I will keep wasting my time.

wierdscience
03-06-2005, 08:57 PM
<font face="Verdana, Arial" size="2">Originally posted by mochinist:
Don't worry weird, I make it a point not to work for a-holes that think they know everything.</font>

So do I,all I am saying is the key slots are there for a reason,not for looks.

hsmike
03-06-2005, 09:44 PM
Why don't you put the vise on with the keys, Then check with a indicator? Keeps everybody happy....

Mike

spope14
03-06-2005, 09:56 PM
Heck, I run vises with keys, and those without. My Kurts did not come with keys. Wish they did,and i would run all with keys.

I have made my own jaws. Warning here. Soft jaws are great, but using them for common holding, be sure to avoid any chip clamping between work and he jaws, They can pick up the chip and repeatedly put the chip mark in a part. I know we are all careful but.....

I have milled steps in soft jaws at times for special holding.

NOW FOR A SECOND THING IN INDICATING!!!!!

Many people forget the check the base for parallelness to the table/ spindle. I mean check the base where you put your parallels on to be sure the vise can hold parallel of a milled top to a bottom. Think Kurt is perfect, well, they are pretty darned good...BUT...bought a used Kurt for about $25.00.. Also a few "Import" vises as the schools just love "lowest bidder", and before I knew the tricks to specifications, got stuck with six of these. Three could not hold X axis parallel, and the Kurt was .002 out over the X axis, and .004 in the Y over 6 inches. Checked the the bottom parallelness, and found I had to shim all over the place on both X and Y. Bases were not burred or dinged. Once done, I engraved the shimming on the base at the shim points and have always held this base indication true - until I finally got the time to grind the tops and bottoms in right (which many of us do not have surface grinders to do, thus my warnings about the base parallel). This indicating is done from the spindle, not the table of the mill, for the spindle is the "cutting action", and a mill table and draging an indicator with a base on a table to indicate a vise has three points of error (base of indicator, table, and dragging movement of indicator over slots) where indicating from the spindle has one (dragging movement) if that.

The basics of squaring have been covered quite well, just adding an additional idea here.

wierdscience
03-06-2005, 10:25 PM
Scott,I know what you mean about the bases,I don't think I have seen many that were flat or paralell.
The Kurt and the clones at work I check end to end every year or so.I have on several occasions stripped both jaws off and surface ground them back flat along with the bases.Made a big difference.

spope14
03-07-2005, 09:10 PM
Yes, base indicating is too often forgotten. After posting this, I st up the class to do it today - pulled out the old shims and everything, and shimmed up the good ones to be out. Proved my point. The troops indicated the solid jaws as true as could be (I use .0001 indicators to indicate, got all within .0005 or better taking into effect some jaw warp in a couple - but we gound jaws two weeks back). had them cut to parallel an perpendicular - this to test their knowledge and skills in base indicating BUT also for an alterior motive to test my flexing solid jaws and a new procedure of clamping. They had done baes before very early this year, they showed they can get "lax" in procedure, but were reminded quickly.

Got this point across, and the troops learned a valuable lesson.

Glad this topic was posted, reminded me to teach this aspect again for re-inforcement.

Jim Luck
03-07-2005, 09:50 PM
Damn, its never takes me more than two-three minutes without the keys!!!!!!!!!!.

[This message has been edited by Jim Luck (edited 03-07-2005).]

Jim Luck
03-07-2005, 09:52 PM
Damn, its never takes me more than two-three minutes without the keys. AM I DOING SOMETHING WRONG?

mochinist
03-08-2005, 09:06 PM
Yes Jim Luck you are, you could save 1 1/2 minutes by using the keys. Hope their is no dings or worn spots in your table slots though. Guess you could use the keys and check it with an indicator but that would kinda blow the whole point of using the keys.

Someone wrote if you need those kinda accuracy's you need to use a surface grinder, stay out of my shop then cuz you couldn't handle it.

Jim Luck
03-08-2005, 11:23 PM
Mr Mochinist --- Why did'ent I think of thaaaat!. Heck, I got the keys, just figuered it was to much work puttin em on. Then again, maybe I'll just do it my way -- can't teach an old dog new tricks ya no!, besides it impresses the beginner's!. Thanks for your insight anyway!!!