Setting a Machine Vice Parallel on the Mill

[Anonymous]

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

[CirclipParticipant @circlip]

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.

[Clive FosterParticipant @clivefoster55965]

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

Clive

[HopperParticipant @hopper]

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.

[Neil LickfoldParticipant @neillickfold44316]

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.

[JasonBModerator @jasonb]

My method is in the current MEW

[blowlampParticipant @blowlamp]

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.

[JasonBModerator @jasonb]

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

[Anonymous]

Posted by blowlamp on 23/08/2018 12:37:28:

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

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

Andrew

[KWILParticipant @kwil]

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.

[Tony Pratt 1Participant @tonypratt1]

Posted by Andrew Johnston on 23/08/2018 14:31:51:

Posted by blowlamp on 23/08/2018 12:37:28:

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

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

Andrew

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

[JasonBModerator @jasonb]

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

[John ReeseParticipant @johnreese12848]

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.

[SillyOldDufferModerator @sillyoldduffer]

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

[David TaylorParticipant @davidtaylor63402]

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.

[Mike PooleParticipant @mikepoole82104]

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

[thaiguzziParticipant @thaiguzzi]

Posted by Andrew Johnston on 23/08/2018 11:24:00:

Posted by thaiguzzi on 23/08/2018 10:03:31:

I though this was just S.O.P?

Well that was a waste of internet bandwidth; copying the whole of the original post just to make a zero content comment. It's the electrons who whizzed around the world to no avail I feel sorry for.

Andrew

I find the "SOP" of tramming a mill vise faster and easier than the other common uses of a DTI, ie tramming the head of a mill, clocking holes to the centre of a mill spindle or 4 jaw lathe work.

I tram my shaper vise regularly as it often goes from parallel to the ram to 90 degrees off due to workholding size problems.

Thank you for your snide comment.

Maybe its because i'm just thick with computers or i was unable to paste & copy.

Either way, have a wonderful day.

[SillyOldDufferModerator @sillyoldduffer]

Posted by thaiguzzi on 28/08/2018 05:50:44:

Posted by Andrew Johnston on 23/08/2018 11:24:00:

Posted by thaiguzzi on 23/08/2018 10:03:31:

…

…

…

Maybe its because i'm just thick with computers …

…

Not at all. Quite a few haven't spotted that you can edit original posts after pressing the Quote button, and/or that fresh typing should appear underneath and after the sidebars. The forum isn't the most intuitive software on the planet!

As far as I know there isn't an edit approved style. I like to leave the names in and use ellipses (…) to show where I deleted something. The main advantage of editing is to focus reader attention on a particular point by removing everything else. It also means the reader doesn't have spend time re-reading the whole post.

Editing someone else's words can be dangerous; it's not fair to deliberately mislead by taking words out of context, and I've done that by accident a few times. People sometimes complain when their name is left in when their contribution had nothing to do with controversial developments.

Dave

[merlinParticipant @merlin98989]

Years ago I aligned the mill vice as accurately as I could, then drilled and reamed through the vice base and the table and fitted a couple of silver steel dowels with a knurled knob on top.

I also did the same through the vice into its base fitted with 3/16 inch dowels.

Putting the vice assembly on the clean table and insterting the dowels then tightening the tee nuts is the work of a few seconds.

after pulling out the lower dowels, the vice can be slit aside or to another angle without having to upturn, slide out any strips and clean it before further use.

The old workshop vacuum cleaner takes away any swarf in ther holes, I guess: i have never had any bother with slipping the dowels in.

I could send photos (if I can manage it) but the job is so simple that there is no need for them.

[Ian PParticipant @ianp]

The vice I use for most of my milling has grooves down each side for clamping down and being hardened has no facility that would let me attach a strip to locate it the T slots (its similar to the Arc type 3). The vice is described as precision and although not designed for heavy milling it does what I want of it.

I have aligned this with 0.001mm scaled DTI registering on a 12" length of ground stock clamped in the jaws and can achieve less than 0.002mm deviation, but its a faff!

I now use a square off the back edge of the table to align the vice. I was pleasantly surprised to find that its alignment is within 0.002mm every time, as long as everything is clean and I set the vice against the square carefully. The square is about a 10" one made of a 'L' shaped plate with a 'foot' fixed to the stock so it conveniently sits against the table edge.

My instincts tell me that a guide strip in a 'T' slot might be able to work to the same level of accuracy/repeatability apart from the fact that the slot surface finish will only be roughly machined, whereas the table edges are more likely to be ground or at least finely machined.

Ian P

[Douglas JohnstonParticipant @douglasjohnston98463]

Thanks for the definition of S.O.P. , I had forgotten I asked that a few days ago! I am now at an age where I seem to have to forget one bit of information before I can fit in a new bit.

Doug

[Mark RandParticipant @markrand96270]

Posted by SillyOldDuffer on 27/08/2018 09:48:07:

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.

Bugger! That hurts.

On the comments about keys in the bottom of the vice to align with the T slots, when I rebuilt my milling machine, the one set of surfaces I didn't bother to re-align and re-scrape were the table T slots. I felt that they weren't a part of the precision of the machine. I guess, if I found a couple of months spare, I could go back and re-do them. Until then, I'll use the DTI on a stick off the side of the head to check the chucks.

[thaiguzziParticipant @thaiguzzi]

Posted by SillyOldDuffer on 28/08/2018 10:56:08:

Posted by thaiguzzi on 28/08/2018 05:50:44:

Posted by Andrew Johnston on 23/08/2018 11:24:00:

Posted by thaiguzzi on 23/08/2018 10:03:31:

…

…

…

Maybe its because i'm just thick with computers …

…

Not at all. Quite a few haven't spotted that you can edit original posts after pressing the Quote button, and/or that fresh typing should appear underneath and after the sidebars. The forum isn't the most intuitive software on the planet!

As far as I know there isn't an edit approved style. I like to leave the names in and use ellipses (…) to show where I deleted something. The main advantage of editing is to focus reader attention on a particular point by removing everything else. It also means the reader doesn't have spend time re-reading the whole post.

Editing someone else's words can be dangerous; it's not fair to deliberately mislead by taking words out of context, and I've done that by accident a few times. People sometimes complain when their name is left in when their contribution had nothing to do with controversial developments.

Dave

Thank you.

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by Ian P on 28/08/2018 19:27:43:

I now use a square off the back edge of the table to align the vice.

Yes, I've done that for years just using a 6" M&W square against my homemade vice. Never had any problems.

Russell

[Andy PughParticipant @andypugh44463]

Another idea that I have seen in that internet.

Get a piece of ground material, ideally the same thickness as the T-slots, but not necessarily.

Cut a big inverted U-shape out of it so that the horizontal section can be gripped in the vice and the legs reach out round the vice and into the T slots.

Grip this fixture in the vice, push back against the T-slots, tighten the clamps, remove.

 

This aligns to the T slots, not to the travel axis. For real accuracy the DTI in the spindle is the only way.

Edited By Andy Pugh on 11/09/2018 10:51:50

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