Setting a Machine Vice Parallel on the Mill

I think it was well worth sharing, not least because of the alternative suggestions it got.

Besides, it's unwise to assume there's any such thing as 'standard operating practice' in the duffer workshop!

Dave

Dave, I think sometimes it helps to be anal about some things. I turned up some thick washers and use flange nuts on my mill vice. It looks like you’re a bit tight for space on yours though.

As I mentioned in another thread. A professional machinist I know of drilled right through his vice into the table for a couple of pins. Setting up his vice now takes no longer than bolting it down.

What on earth does S.O.P mean?

Doug

Standard operating procedure?

Tony

The answer is Standard Operating Procedure. I'd agree with SoD, except to say that it probably isn't SOP even in professional machne shops. Every one will have it's own ideas.

Andrew

The late Sir John (RIP) advised the "Goalpost" plate clamped in the vice yonks ago for rapid setting, but he was only working to RR standards, not NASA

Regards Ian.

Only universal SOP I know of is "verbal encouragement" in steadily rising volume and profanity.

Clive

SOP in some machine shops is to clamp a length of ground square bar or similar to the table, set dead parallel to the traverse. Then flip your vice upside down and clamp it onto the square bar. Then machine a slot across the vice base the same width as the Tee slots in the table. Put a piece of neat-fitting key steel or similar in the slot and hold it in place with a couple of socket head cap screws in counter bored holes.

So to set the vice up nice and straight is then just a matter of setting it on the table with the key steel in a T slot. Or if you want to set the vice at an odd angle, two screws and the key steel comes off.

A great topic Andrew. I have seen where some use a single (pivot) tennon to adjust the vice on. Like you say , it takes less that a few minutes to set to within 0.01mm over the length of the vice. To get better that 0.01mm over the length of the vice, it needs to be clamped with a reference of some descript.

My method is in the current MEW

Has anyone else used their DRO feature-set to adjust a vise to a precise angle?

I've done it a couple of times with pretty good results.

Fine setting a vise is a good case where a swivel base can be useful.

Martin.

I've mounted mine on the rotary table a few times when I have wanted the odd angle, just clock in the fixed jaw when table is at zero and then you can set the angle you need with the R/T and a lot more accutrate then the scale on the average swivel base. 

Edited By JasonB on 23/08/2018 13:23:01

Obviously not in my case, because I'm not sure what the technique involves?

Andrew

Martin,

Yes, it works fine, also useful if you want to tilt something in the vertical plane that is held in a vice. Simple right angle triangle calc of course.

Say for example you want to set the vice at 45 degrees. Set the vice to 45 degrees approx, touch DTI stylus on vice jaw & zero dial. Move 25mm in X and 25mm in Y to contact the vice jaw again. If the DTI shows exactly zero the vice jaw is at 45 degrees. Adjust as necessary.

Tony

When using the DRO you don't need to move 25mm by 25mm.

You set the angle into the DRO and anywhere along that angled line the DRO will read 0-0 which allows the DRO to do the maths rather than you having to work out the X & Y amounts. When DTI also reads zero at any position you then have the vice at the required angle.

Edited By JasonB on 23/08/2018 15:07:47

Vic pointed out that his vise had provision for dowels to align the vise o the T slots. Most vises I have seen have slots for keys to align the vise to the table slots. I think it is foolish not to take advantage of them. It may be necessary to make stepped keys to properly fit your vise and the machine table. For owners of Kurt vises or their clones Kurt sells stepped keys that only cost one arm and a leg.

My vise is keyed to the table. If I need to get the vise out of the way I just loosen the bolts ans slide it to the end of the table. I can slide it back to the middle of the table and it is perfectly aligned. No clocking.

My original problem (taking 40 minutes to align the vice) turned out to be caused by the idiot wielding the hammer.

The vice in question is a DH-1 and its design allows jaws to be mounted in various positions. Very useful sometimes. However, unlike most vices, it is the rear jaw that moves.

I wasted 40 minute by positioning the DTI on the loose rear jaw. Swivelling the vice by tapping also moves the slide. Not much, but a 0.2mm shift is massive when trying to align the vice to 0.01mm.

The problem is cured by either gripping something in the vice so the moving jaw can't shift or to put the DTI on the front, which is the fixed jaw in this photo.

What's curious about this fiasco is I've been successfully aligning the vice for over a year. Somehow after a week playing rotary table I forgot about the moveable jaws and tried to align it as if it were my other Kurt-style vice. Habit is a monster. Either that or I'm losing my marbles!

Dave

Well, a rear moving jaw probably would cause some confusion amongst most of us once we'd put it away for a while and forgot about it!

It's a worry how long simple problems take to clarify sometimes.

I purchased a very large parallel to help setting up my vice, it gives a long clean face to gauge on and I find it useful.

Mike