Squaring up a mill vise

[RobWA]

First I apologize if this is the incorrect forum, I was trying to figure out where to put it.

So long time lurker, first time poster here. I'm new to the world of machining. Lost my job last year and then went out and promptly spent all of my savings on tooling

I picked up a 5" Kurt clone milling vise from Glacern a couple weeks back and today I actually took the time to mount it to the bed of my machine. I pulled out my fresh out-of-the-box DTI (0.005" graduations) and went to town trying to square up the vise. I had one heck of a time trying to figure out what all was going on here. After about an hour of tapping gently here, tapping gently there, this is as close to square as I can get the dang thing. No manner of tapping seems to want to square this up.

Quick background:
So in this video I've got the DTI turned around on the movable side of the vise jaw and while I know this is NOT, NOT the way to do it, video taping it facing the column would've been harder but the readings shown are identical to the readings from the stationary vise jaw.

I locked down the one axis, locked down head, and cleaned the bed AND base of the vise very carefully and meticulously before fastening it down for squaring.

I can't figure out why on earth I'm getting these readings, I figure someone here in the forum would quickly be able to identify the issue. It seems almost as if the bed isn't square on the machine (Sieg SX3). But I do not see how I would able to adjust it square.

Help is greatly appreciated! Thanks guys/gals.

-Rob

[RobWA]

Video: 2012-02-01_11-42-41_118.3gp - YouTube


Forgot to add it!

[fizzissist]

Am I missin' something? Looks like your vise simply isn't square.

Position the vise on the table so the slots for the hold down bolts are centered over the slots in the mill table. This will allow the vise to pivot enough to get it squared.
Tighten one of the two bolts holding the vise down pretty firmly, but not tight. This will be the pivot bolt. Tighten the other bolt not quite as tight. Now start running the table back and forth with the indicator on the stationary jaw. (yes, lock down the Y axis) While you're running the table back and forth, tap (with a bounceless hammer) the part of the base furthest away from the pivoting bolt until the indicator doesn't move. When it's as good as it's gonna get, tighten the other bolt, then tighten the pivot bolt.

A good machinist can square up a vise within .001" or so over 6" in a couple of minutes or less. How quick depends on the phase of the moon, which socks you put on that morning... sometimes you get in a few sweeps, sometimes it pisses you off. Comes with the territory. By the time you're 50, you'll have it nailed.

[mcarvey]

Welcome! And glad to hear that you got a decent vise- it will make your life SO much easier compared with the cheap import ones. So one benefit of getting a nice new vise (like a glacern) is that you can be pretty confident that the vise itself is fairly square. Not to say that you shouldn't check it, but it does help to show that when you first get it, the mill itself is not often square/in tram. There are many posts on the subject so I won't go into it in great detail, but the first step is to make sure that the column is square to the table. That is, if I put something perfectly square on the table (whether 2-4-6 blocks or a cylindrical square) and put a dial indicator on the head, the dial indicator doesn't move as you raise the Z axis (in both X and Y) If it's off by a lot you may need to shim the column/adjust the leveling of the mill. Once that is reasonable you need to tram the head (get the angle in the theta/phi direction) level to the table. This usually involves rotating a dial indicator mounted a few inches from the spindle axis to make sure that everything is as good as you can.
Once the table is trammed you'll probably find that squaring up the vise is a bit easier. But you definitely have the right idea. An hour or so of dial indicating, tapping with a rubber mallet, and crossing your fingers is pretty much a right of passage for first time mill owners. Or at least it was for me
Please, anyone chime in if I mistyped- it's getting to be bedtime.

-Matt

[Shargo]

First since it's a new vice turn it over and inspect the bottom. Flat, no highspots or sharp edges? If so fix it or return it. The same goes for the mill table, both should be covered with a thin layer of oil (to allow for smooth adjusting and rust protection). The mill table should be completely clean, no chips even in the T-rails!

Now use a sturdy (at least 10mm thick) parallel to check the jaws on the wise - Are they both flat and nice?
Lightly clamp the parallel in the wise, is it smoothly and evenly gripped?
If you cant get a satisfactory grip on the parallel you wont on your workpieces either but the hardened parallel is even more demanding.

Let's mount the vice on the table. Clean, smooth and nice with a hint of oil. That even goes for the T-bolts! Remember, sharp edges will bite. Make sure there's a washer between vice and nut.

Personally I like to use four fixation points, put them all in loosly and eye-ball it in.
Chose one and tighten it slightly with a wrench, this'll be your turning point.
The nut opposite the turning point should now be tighten fingertight or very loosly with a wrench.
Lock all axes but the one you are setting it parallel to (X assumed here).

Now mount the parallel so about 10mm is above the vice jaws and over 50% (2/3 preferable) of the jaws height are used (can be done with less but don't tighten to hard then). Viola, you got a nice surface to measure on that is parallel to the fixed jaw and easy readout on the indicator

Check the wise with the indicator, adjust as necessary.

Two important things:
1: Use your hand or no-bounce hammer to tap the vice.
2: The vice will not turn around it's center but around that tightened bolt!
The second point leads to that the vice is slightly moved forward and backward so you will need to re-adjust your indicator and/or table to compensate. Remember to unlock and lock the other axis when doing this.

Now when satisfied start tighten the other (three) nuts, do this in a cross pattern and check after each nut! You will probably need to go around three or four times before full torque can be set, if you tighten to full directly the vice will move and if forced back you will have evil tension in there (that are bound to pop up create problems later, probably when making the finish run...)

If this seems tedious and overdone remember that no part you do will be better then the setting of your vice

Good luck!
Did I mention that all surfaces must be clean and smooth?

(Oh and if this doesn't help, please post another vid but adjust a few things:
Focus
Step back or zoom out so the whole setup can be seen
Use a parallel as above for correct readout
Have some "lead in and lead out time - start the vid before things starts to move and the same at the end"
Multiple passes)

[oorx7]

First time posting. Glad to see the positive comments to help out on this forum! I have been a machinist since the early 90's. I was just going over this procedure with one of my apprentices today. This is one of the most important things in machining, if you ask me. Its all about the set up.

Any ways, All the advise that was giving is spot on. After watching the video, I think that you have your indicator touching the movable jaw of the vise. Its hard to tell though. you always want to tram in the stationary side. The movable side has play in it to take up any parallelism in the stock that your machining.

Also read you indicator instructions, chances are the angle that the stylus is related to the work piece should be at a certain degree to get an actually measurement reading. My interapid must be at a 12 degree relationship to give a true measurement. I how ever rarely use my indicater as a measuring tool. I try and stress that is best meant for comparing and picking up my work pieces.

Hope that helps;
Brandon

[79TigerPilot]

As others have indicated use the fixed jaws. If you have chewed up soft jaws clamp up a thick parallel and indicate that.

I don't look at the numbers on the indicator but the rate of change in the pointer. Use the power feed or in my case a simple G-Code program to sweep left and right across the jaws at a medium slow speed. Watch the pointer while you tap the vise. You want to tap in the direction that reduced the pointer's movement. First tap will tell you if you are taping the correct side of the vise or you need to tap the other side. The trick is to tap only when the indicator is moving across the jaws. No pointer movement indicates you are parallel.

Craig

[Shargo]

Well he did say he used the moveable jaw to be able to capture the video.

[tmcallister74]

"Lost my job last year and then went out and promptly spent all of my savings on tooling"

Back that truck up. Beep, Beep, Beep,... Ummm ok never mind the job thing I'm over it.

It looked like you had your indicator zeroed in the middle of the vise. I have found it easier to zero it on the side of the vise jaw that has been tightened down then when you tram to the other side you can tap it until it is at zero also.

[RobWA]

Thank you very much for your help, I was READING it as JUST THAT (negative, zero, negative) my brain was just simply NOT interpreting what was exactly right in front of me. I do very much appreciate your guys' help. I'm learning but also trying to make a living on what I'm doing. So there is an added stress there to get it right. I've got background in CAD design but until just recently never touched a milling machine. I figure why pay someone else when I can learn such a valuable skill?

Thanks again, I knew I'd get turned around the right way


-Rob

[fizzissist]

Good. Now don't do that again.