Tapping in a vice

[John Gray 7Participant @johngray7]

I know this has been covered before, but humour me please. After some weeks away from my workshop following a hospitalisation spell, I spent an hour or two today just “doing stuff” that needed doing. One of the things I needed to do was to remount and clock in my arc versatile (without the swivel base) vice. I have researched other people’s approaches and intended to machine a top hat type washer to fit to one side that could be tightened up with the other side loose to enable tapping in. I found there is not really room for that type of washer unless I mill out a little space. This is still a possibility. I used the 2 mounting bolts with one snugged up to pivot on and one loose. I was astonished at how long it took me to get this anything near right, and I think I need a better solution, as I would like to not feel bad about taking the vice off. I don’t have the same problems with my 70mm toolmakers type vice as this has flat machined sides, and use of an engineers square gets me close enough for most activities, or can be proper sorted with a clock and a few taps. The versatile vice doesn’t have machined edges so this approach is not possible.
the vice came with a couple of keys that will have to be machined to fit the slots on my SX2P mill. My thinking is to machine these 2 keys to fit the slots then try a clock and see how close I am. If I push the vice forward so that both keys are in contact with the edge of the slot, I’m thinking that I could alter the position of the vice minutely by milling or grinding just one key, rinse and repeat until it’s correct. This sounds to me to be too good to be true, but the allure of being able to remove this vice and replace at will with a workable setup is messing with my head.
My second plan is to mill out one of the mounting lugs and make a bush or top hat washer to fit such that the vice could swivel about this point, presumably making tapping in easier. I found today that with one side snugged up there was just too much movement on the vice in all directions rather than just pivoting about the snugged up point, and I’m sure that that was what was making my task so difficult. I imagine practice and experience would help here, but it’s not encouraging me to take it off just so I can practice and get some experience tapping it in again. So what do folks think, fit and fiddle with the keys, or mill the vice base, or indeed both options?

[John HaineParticipant @johnhaine32865]

The technique for fitting keys to the vice (highly recommended) is as follows.

• Clamp a bar across the table deal square to the X direction.  Ideally use a big parallel.
• Turn the vice upside down and clamp its jaws on the bar, then machine a shallow groove wide enough – say 1mm –  to take a square key blank that is slightly larger than your tee slots as a tightish fit.  Make the groove in line with the mounting holes.
• Tap a couple of holes say M5 in the underside of the vice on the centreline of the groove to match clearance holes through the bar.  Good idea to counterbore the holes in the “top” of the bar (which will end up on the bottom).
• Attach the key blank with suitable bolts (socket head probably best to get them really tight).
• Beforehand you should very accurately measure the tee slot width which the key will drop in.  With the inverted vice clamped in place and the key firmly bolted on, take very small full-height cuts either side of the key to get it to a width which will be a snug fit in the slot.

Now, as long as the initial bar was accurately square to the X axis, you should find you can drop the vice in place with the key in the slot and it will be dead square.  I did this years ago and stopped worrying about dialling in my vice.

[HuubParticipant @huub]

I clamp a piece of flat stock in my vice (123 block) and register that against the flat side of the Z-axis using a flat and parallel piece of aluminum. Than I tighten the bolts and 9 out of 10 the 80 mm vice is within 0.02 mm (0..1″) aligned. For 99% of what I do, that is close enough.

I made the aluminum parallel by milling 1 side, placing that milled side against the flat Z-axis and milling the opposite side. Added a mark that shows the side that needs to sit against the Z-axis.

[JasonBModerator @jasonb]

I covered fitting the keys to one of these vices a couple of months ago in MEW, will add it to the “Workshop” section of the forum later this morning.

This0.005mm over the 80mm jaw length is good enough for most work though I can clock my other vice without keys in less than 60 seconds so your tapping method may be the problem.

[DiogenesParticipant @diogenes]

Without wanting to sound like an ar*e, it is ‘developing a feel’ that makes it a quick job – I push my vice ‘back’ so that the bolts are against the edge of the slot and ‘snug’ both bolts reasonably firmly (- if you leave one slack, the vice will move as you nip it up) –

– most vices/keys will be nearly there by now, so it’s a question of shifting the vice a little at one end, tapping on it’s own is a bit hit-and-miss, you need to apply some pressure with the other hand, in the direction in which it needs to go, so that there’s some control and ‘damping’.

A little hammer made from something ‘dead’ but without to much ‘give’ (copper – cut up an old soldering iron from a boot sale) works better for ‘precision’ tapping than something soft like hide, plastic or lead.

 

[JasonBModerator @jasonb]

Now on the website under Workshop

[Nicholas FarrParticipant @nicholasfarr14254]

Hi, I’ve always trued my vices by the same method as in JasonB’s video. Using keys is fine, as long as the slots in the table are true and parallel to the X axis, but I’ve never found the need for using them, and I have vices that have no prevision for fitting keys anyway.

Regards Nick.

[John Gray 7Participant @johngray7]

Thanks for your replies guys. I’m sure it is my tapping skills or lack of that is causing me a problem. Jason B you wouldn’t believe how long I have spent searching for the article you did on fitting keys! I thought it was longer ago than it actually was and so I had missed it, but remembered I’d seen one. Il just put it down to old age and stupidity. Thank you for reproducing it here for me, I’m going to have a go at this, and as far as I can see, even if I mess it up a bit, it should get me into the right ballpark. Next time I feel able to do a bit of workshop time I’m going to give it a go, thanks to all for your replies.

[John Gray 7Participant @johngray7]

So this evening I thought I would just have an hour and have a look at this. I dug out my gauge blocks and had a proper measure of the slots. For some strange reason the nearest slot to me is narrower than the middle and front which are the same. The supplied keys with the Versatile vice will not do to fit to a SX2 mill, as narrowing them will cut a good way into counter sunk holes for the largish fixing screws, leaving very little bearing metal. It seems to me that the simple answer is to make new keys. So will ordinary scrap bin mild steel be ok for these or will it require tool steel or some other grade of steel?

[JasonBModerator @jasonb]

Does not need anything special

[Clive FosterParticipant @clivefoster55965]

As regular readers will know I’m no lover of keys for vice registration. If they are tight enough to be really accurate they can make it a right pain to get the vice up and out. And don’t get me started on worn / slightly damaged slots on older machines or not quite dead nuts equal width ones on affordable machinery. (Guess who jammed a keyed vice into the table slots of a square column mill so hard as to be almost impossible to remove when the slots turned out to have a teeny-weeny bit of vertical taper on the sides! Learning experience about the dangers of giving things nice firm push into place.)

Quickest and easiest way is to simply clean up the vice fixing slots with it inverted and gripping an accurately aligned bar as describe by John so the sides are accurately aligned. Then copy Diogenes by simply pushing or pulling the vice so that both fixing bolts or studs are hard against one edge of the Tee slot.

A slightly more engineering approach using the same push agains the sides registration is to fit a simple pair of round bobbins to the vice base in suitably counterbored holes. Make them a nice free sliding, but not rattling, fit.

The push against the slot side method is easily repeatable to better than half a thou per inch / 0.05 mm in 10 cm taper. I get about half that. But I have the rotating base under my vices, plenty of head room on a Bridgeport, so it’s easy to take out the degree or three error in the slots as cast.

If you haven’t done so do check how good simply pushing or pulling against the bolts is. I believe Jason reported that one of his was so accurate as cast that attempting anything better was pretty much superfluous.

One advantage of the bobbin method is that if you do have a brain fade and get the holes touch out of line just adjust the diameter of one bobbin to make it all come right. The counterbore fitting is for accurate replacement if you need to pull one out when Inspector Meticulous decrees that absolute perfection is essential and you have to resort to tapping using the other bobbin as a pivot.

Clive

[peter1972Participant @peter1972]

I have carefully milled a length of T-section that I simply drop into a T-slot before mounting my vice or swivel base. Good enough for my requirements!

[JasonBModerator @jasonb]

Tight keys are not a problem if you do it as per my article where I make them just narrower than the slot. Just push the vice back against the edge of the slot as you tighten it up.

Some mix up in what I said. I do not push my unkeyed vice(s) against its bolts. I just eyeball it and nip up the nuts then tap it while moving the table and watching the dti. I’m not looking for a number at each end to match just no movement of the needle. I do have  agood eye to start with so can get it set quite quickly.

[Howard LewisParticipant @howardlewis46836]

It is not feasible to put keys on my vice, so I made an alignment jig, like a goal post.

The bottom of the two uprights was turned to be a snug fit in the T slot on the mill table before being drilled though.

The “cross bar” was milled with Vees, to locate against the uprights, and then clamped in place at a suitable height for the vice jaws, before drilling, and tapping the uprights, for the securing capscrews.

The assembly is secured by long studs, fixed into T nuts, with a hut on the top.

Once in place, a light cut is taken along each side of the crossbar, so that when the vice is clamped to the “goalpost” the jaws will be in the plane of the cutter.

Once the vice is secured, the goalpost is removed, and work can begin.

Howard

[PeteParticipant @pete41194]

Using or not using keys in any table mounted mill tooling will always come with trade offs no matter which you chose. Then there’s vises that never came with the slots to use keys, or the precision hardened and ground tool maker or grinding vises that many are using. Then it’s not exactly uncommon on some of the smaller sized bench top mills and the smaller vises that might have varying sized or out of square table tee slots, or the same for those vise key slots, then what?

I know my own mill table has fairly accurately sized and parallel tee slots, my own mill vises even came with the slots and keys that closely fit my mills tee slots. I’ve never bothered to bolt them to my vises. 15 minutes of your time and this video will show why. If it takes you longer to tram in any mill vise than 60 seconds after a bit of practice, your doing something wrong as the video clearly demonstrates. It’s all about that bit of practice, developing a feel for how tight to initially have the one bolt tightened the vise pivots on, and then how hard or light to tap on the correct side of the mill vise, as well as understanding which direction to go to end up with a zero – zero indicator reading. Even when using keys, most would still double check the vises exact alignment with an indicator anyway, so they gain you very little. Since adopting the same method in the video, I don’t even think about removing a vise any time I want to. https://www.youtube.com/watch?v=R_l2dhpIOLY

[Michael GilliganParticipant @michaelgilligan61133]

Great video, Pete

… All good sensible stuff

[ obviously easier with the motorised table, but the principle is valid anywhere ]

MichaelG.

[JasonBModerator @jasonb]

Another reason why I suggest not making the keys a tight fit, if you have a need for better than the keys provide then you can just tap it in for those final 5microns. But for a lot of work the keys will get youwhere you need to be or in the ball part to start clocking.

[old martParticipant @oldmart]

I have always used the vise inverted clamped to a parallel or 1-2-3 style block method. This is for the final truing up skim of the new key/keys fitted to the groove that most vises have from new. Both 100mm Bison vises have their keys matched so they can be used as a pair for long work. The need two sets of keys for each vise as the round column mill has slots wider than the Tom Senior ones, and they are marked as to which vise they fit and which way round they go.

I did find that the rear of the slot in the round column mill which was the best one for the Bison vises was not parallel to the X axis. Most of the slot was ok, but about 1/3 of the left end needed up to 0.007″ removed. I milled the entire length starting with a 0.002″ cut at the right end and finishing with 0.009″ at the left end. I had to do this in three stages, taking advantage of being able to swing the head far enough either way to reach the entire stroke of 500mm of the bed. The rear of that slot is within 0.001″ of true which is good enough for me. I have not checked any other slots for errors, one was enough.

The other thing that happened when the Tom Senior was ready to cut metal had me fooled for some time. I made narrower keys for the vises and used one of the 2-4-6 blocks that I had bought secondhand on ebay a year or two earlier. Both vises were out of alignment after finishng the rear of their keys. I did get the keys trued up later. The culprits were the 2-4-6 blocks, and I only found out accidently weeks later when I had them standing together on the surface table. The bottoms were touching and the tops had a gap. There was not a true square corner. They have since been surface ground free of charge by the friend of another museum volunteer.

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