Setting Milling-machine Vice

[Nigel Graham 2Participant @nigelgraham2]

I'm sure this must be an old dodge but I've not seen it described anywhere…..

Setting a vice to be parallel to the table travel usually involves a gentle tap here, a run across with the DTI, a gentle tap there, ditto; oops too far; repeat several times, have a cup of tea; a gentle tap here…..

So:

1. Clamp a longish, straight length of BMS bar centrally in the vice, just nip the vice holding-down nuts or clamps. Fit two small angle-plates to the outer T-slot.

2 Tighten a long bolt fitted with two nuts in one of the angles, with its tip against the face of the straight-edge close to the end.

3 A second bolt with two nuts in the other angle, but leave it just slightly loose.

4 Keep the straight-edge against the first screw, which thus acts a fulcrum.

5 The other screw therefore acts as an adjuster, with the DTI used close to the screw at each end in turn.

Further, I did not traverse the straight-edge along the DTI tip. Instead I clamped the DTI's magnetic stand to the vertical shears above table, then used the DIT in conjunction with the cross-feed dial; moving the table back before traversing it to the other test-point. Measuring both ends ensures keeping the fulcrum in contact and removes any slight off-set effect.

Finally, a few spot-tests along the bar to smooth out any slight defects in the bar ensured consistency, then a run along the section actually projecting above the jaw as a final test.

It sounds a faff but is easier to do than describe, and proved quick and efficient. The angle-plates don't have to be proper precision angle-plates either, as long as they are rigid. Mine happened to be, but more by instinct than deliberate choice, as they could simply be a couple of off-cuts of reasonably heavy "angle-iron", with tapped holes for the adjustment screws.

[Nigel Graham 2Participant @nigelgraham2]

[Jeff DaymanParticipant @jeffdayman43397]

Or you could true it up once, then drill and ream for a pair of dowels as far as possible apart on the base, like the guy who owned my old RF30 mill did before me.

I can get the vise on and off in minutes and so far it checks true/parallel to about a thou every time.

Just food for thought.

[Enough!Participant @enough]

If the vice has a through-hole to the table, you can machine a block that clamps in the vice and projects down into a table slot. That way you have no permanent projections from the vice and it can still be fitted in any orientation. (In fact you can machine the locating block – or use a second – so that you can fit the vice in either perpendicular orientation).

[Richard –Participant @richard-3]

If you keep one bolt on the vice tighter than the other it will act as a pivot and you will be able to set it parallel very quickly,

No need for anything else,

Richard

[Chris Evans 6Participant @chrisevans6]

I am with you Richard-, just nip one bolt and true up in less than a minute. No other junk to put away afterwards.

[Michael ToppingParticipant @michaeltopping17870]

Surely learning how to clock a vice jaw square is one of the basic skills of machine shop practice, at least it was when I was an apprentice, use the method as Richard states above and it will soon become 2nd nature. I had to mount my vice this morning, lees that 5 minutes and it's square to 2 or 3 tenths and ready to to use. Mind you I have been doing it for a long time now.

michael

[VicParticipant @vic]

Posted by Jeff Dayman on 05/05/2019 00:21:44:

Or you could true it up once, then drill and ream for a pair of dowels as far as possible apart on the base, like the guy who owned my old RF30 mill did before me.

I can get the vise on and off in minutes and so far it checks true/parallel to about a thou every time.

Just food for thought.

Yes I’ve heard of that one. I made a couple of stepped sleeves that are an interference fit on my vice mounting holes and a snug fit in the tee slots. Simply placed on the table with the sleeves in the slots and it’s within about one thou. If I’m really picky I clock it as well but it doesn’t take long.

[Nigel Graham 2Participant @nigelgraham2]

I feel as if I am criticised unduly, but I am not clear on what point.

I was not disputing the need to be able to set a vice or any other work-holding arrangement squarely – I simply suggested a way easier and quicker than tapping things with mallets. That might work for you people who obviously used machine-tools professionally for many years, but most of us on this site don't have the luxury of such intensive experience, because are amateurs who have to work alone, with the largely self-taught skills, the equipment and the time constraints, we have.

A lot of vices don't have accurate faces on any of the sides of the bases; but it may be possible to machine registers on some. The Abwood 6" vice I had for a time had a banjo-shaped, as-cast base, machined underneath of course but not even rectangular. ("Had" only because it was too large and bulky for my milling-machine.)

Actually the vice I was using does not lend itself to using one of its clamp-bolts as a pivot, by its design, if used across-bed.

Others suggest various dowel or tenon fittings – yes, all valid, and chosen to suit the design of the vice.

[JasonBModerator @jasonb]

Posted by Nigel Graham 2 on 05/05/2019 10:20:14:

 

A lot of vices don't have accurate faces on any of the sides of the bases; but it may be possible to machine registers on some.

You don't need any other face apart from the fixed jaw which is the face to clock as that is what you register the work against. I have had no training as I don't have an engineering background and use the slack bolt and just tap the chuck, clocks OK in a minute or less. ( as shown in the latest "milling for beginners out next week)

You don't need to run the dti all the way along the jaw as you can soon see what direction it is moving in and adjust the vice as needed, I can usually get it where I want it before it gets from one end to the other on my 4" vice.

Edited By JasonB on 05/05/2019 10:30:28

[Clive FosterParticipant @clivefoster55965]

Posted by Vic on 05/05/2019 09:57:06:

Yes I’ve heard of that one. I made a couple of stepped sleeves that are an interference fit on my vice mounting holes and a snug fit in the tee slots. Simply placed on the table with the sleeves in the slots and it’s within about one thou. If I’m really picky I clock it as well but it doesn’t take long.

Good one Vic. Been meaning to do something similar for mumble-mumble years but for now the "temporary expedient" of simply pulling the vice back or pushing it forwards so both holding down bolts are hard against the same side of the slots works well enough to similar thou and a (variable) bit over vice jaw width (4 inch) accuracy.

One of the times where retaining the rotary base mount helps. Going by the graduations the tee slot sides on mine are maybe 1/4° out of parallel. Having a Bridgeport means I've got enough vertical table to spindle clearance that the odd inch or so of rotary base thickness is irrelevant for all seen jobs.

Folk with less space should consider machining the slot sides dead true to the vice jaws. Obvious way is invert the vice and grab a stout bar on the machine table trammed dead true to the slots with the jaws. Withe everything made nicely snug sub-thou accuracy when just boring things down should be the norm. When I did something similar for another job I cut the slots a little wider for a snug fitting T washer rather than rely on just snugging up against the bolt. Worked well, maybe ± 1/4 thou accuracy as I recall things, but may have been a refinement too far.

Even after machining the slots you are probably never going to get things dead nuts on to a tenth thou or less so be sensible to make an additional bolt with a slightly reduced shank so you can pivot one side as suggested by Richard. If you make up a two way screw pusher thingy for controlled movement going from close to dead on will be very fast.

As always if something is going to be dead on every time its likely to be too tight to shift easily.

Its worth making decent arrangements to rapidly mount a lever type indicator for tramming purposes. My Bridgeport has a handy boss and clamp screw arrangement on the side so I med up a rod and tilting clamp affair to carry the indicator. Takes less than a minute to set up including the time taken to hook the indicator out of the cupboard.

Clive

Edited By Clive Foster on 05/05/2019 10:41:38

Edited By Clive Foster on 05/05/2019 10:42:07

[Paul LousickParticipant @paullousick59116]

I have machined a keyway in the base of my vice. (Key does not have to be a perfect fit with the slots in the mill table). Just apply pressure against one side of the slot as you tighten the hold down bolts. This is quick and accurate enough for 99% of the machining jobs, as long as the slot is true to the table slide.

Paul.

[Richard –Participant @richard-3]

**LINK**

A quick search you tube, might help?

There are a lot of similar tips,

Richard

[John ReeseParticipant @johnreese12848]

My vise is keyed to the table. No tramming.

[BufferParticipant @buffer]

I think my way might be a little different.

With the vice slightly slack I clamp a long ground flat in the vice then bring a verdict gauge up to the left hand end.

Then with power feed on (or hand wind it) I traverse the table right to left and just tap the vice until the needle stops moving. I dont care what reading it starts or stops on, the needle just has to stop moving. Then nip up the vice, feed back the other way to check and your done. I can normally do it in less than one pass.

Saves a lot of going back and forth thats for sure.

Regards

Rich

[mechman48Participant @mechman48]

Posted by Paul Lousick on 05/05/2019 10:54:22:

I have machined a keyway in the base of my vice. (Key does not have to be a perfect fit with the slots in the mill table). Just apply pressure against one side of the slot as you tighten the hold down bolts. This is quick and accurate enough for 99% of the machining jobs, as long as the slot is true to the table slide.

Paul.

+ 1, Did the same with my set up & works just fine for me.

George.

[Fowlers FuryParticipant @fowlersfury]

The subject has of course been covered before here in May of last year.

On 30/05/2018, I posted "Lining up the milling vice….I'm with Clive F's 4th para "Personally I'm not great lover of keyed vices…. etc"
Easiest & quickest way I've found is to lightly grip a (dedicated) laser pointer in the vice jaws, wind out the table to its stop, rotate vice until laser point lines up with mark on workshop wall and then tighten down.
(To accurately position the target (mark) on the wall the first time, needs an accurate parallel in the vice and a dti)."

Further details & Images shown with that original posting.
**LINK**

I still find it takes about one minute that way and is always accurate.

Edit:- Apologies – I tried inserting link to that thread but am getting error.
This is url in full:-

https://www.model-engineer.co.uk/forums/postings.asp?th=136030&p=2

Copy & paste that into search bar should bring up Google link

Edited By Fowlers Fury on 07/05/2019 12:27:11

[Howard LewisParticipant @howardlewis46836]

My milling vice is set using an alignment jig rather like a goalpost, on my vertical mill.

Two pillars have their lower ends turned to a snug fit in the Tee slot. Across the upper end, in my case located by Vee slots, is fixed a "cross bar, at such a distance that it lies within the jaws of the vice.

The pillars are secured by long bolts running through them into Tee nuts in the slot. Once secured in place, a small cut is taken along each face of the crossbar.

If the vice is clamped to these machined faces, this will lie in the plane produced by a cutter. Once clamped in place, the vice jaws can be opened, the long bolts removed from the Tee nuts, and the fixture removed; leaving the vice aligned and ready for use.

Checks showed that the vice jaw position is repeatably aligned within a thou (25 microns for the modernists)

Howard

[Ed DuffnerParticipant @edduffner79357]

I just bought a set of parallels. Something I want to try if the largest parallel is deep enough, is to set a parallel between the back face of the fixed jaw of my vice and the square column of the mill. Or better still between the column and another clamped parallel in the vice jaws. Then use the Y axis feed to square up the loose vice against the parallel.

I suppose 1-2-3 blocks would do the same.

Ed.

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