Keeping your vice straight

[Blogwitch]

A lot of people already know about this little exercise, but there may be a few who don't.

When you remount your vice to the mill table, it should then straightened up, by running a DTI along the fixed jaw (I prefer to use a parallel mounted in the vice) by feeding backwards and forwards on the X axis. You then gently tap the vice until you get the same reading at either end of the jaw, then the vice is locked down and everything is rechecked again. At times this can be a real PITA, and normally takes about 10 to 15mins to get it spot on.

 

[ttrikalin]

thanks john, very good post and a smart suggestion.

 

[SAM in LA]

Thankyou Professor Bogstandard.

I appreciate that you go to such detail in your lessons.

SAM

 

[Philjoe5]

Neat trick Bogs. Thanks for posting. Something that I need to put on the to-do list.. :bow:

Cheers,
Phil

 

[Omnimill]

Nice one Bogs Thm: I heard of this idea some years ago but not seen anyone actually do it. Must admit that I'm too scared to try it myself as you can bet no matter how careful I set things up I'll still end up with the vice several thou out :'( It has given me a couple of ideas though ...

Vic.

 

[GOOFY063]

thanks very much Mr bogs Thm: that will be a good project for tonight

 

[Blogwitch]

Thanks gents, glad it has given a few a bit of inspiration.

Sam,

I go into so much detail is because without reasons, a lot of the machining processes mean nothing. The reason for say the rounding over, now knowing why I did it means that it can be used in other situations you come across, rather than just me making it look fancy.


John

 

[lee9966]

Great stuff Bogs, it sure is nice to have you posting again.

Clamping the vise upside down for alignment is one of the things I will use plenty of times I am sure, I wouldn't have thought of it on my own.


Were you joking saying .0001 over 5 inches was disappointing???

 

[Blogwitch]

No Lee, it was a way around not looking like I was boasting.

 

[T70MkIII]

2 great ideas - thanks for posting, Bogs. As a less experienced machinist I might try John S' horseshoe method first. Your way looks great, but intimidates the heck out of me and my over-priced vice. Strange, because I can't see much that would go wrong in the process - just a confidence thing I guess...

 

[Blogwitch]

That is usually the main problem with some of my postings Richard.

Because I have done this sort of thing many times, I have absolutely no fear of it, because I know that if I get it wrong, I could easily come up with a repair/fix.

The reason I showed John's 'horseshoe' method, as you call it, is because people like yourself might not have the confidence to tackle what I did.

You will gain that confidence over time, I have no doubt of that.


Bogs

 

[shred]

Good stuff as usual. My Kurt vises come with key slots pre-cut in them, but often the key-slot size and table slot size don't match up. For silly money you can buy 'offset keys', but it's much easier to whack 'em out of some stock. I will have to go round over the edges of mine next I have them out.

 

[Blogwitch]

Shred,

I would be very careful of pre cut grooves. I showed where I did my rotab, and made out the slot was OK, but it was about a full degree out.

I actually trued up the slot and made top hat spigots after I had taken the shots for posting.

You don't need full length bars, you can use round spigots, the same size as your slots (or top hat ones if the slots are different sizes) at either end of the vice slot, you could in fact put an extra one or two in for good luck if you really wanted to.

John

 

[Antman]

That type of step-pyramid hold-down clamp looks like a nice, doable (even for me) project for the shaper.

Ant

 

[shred]

Shred,

I would be very careful of pre cut grooves. I showed where I did my rotab, and made out the slot was OK, but it was about a full degree out.

I actually trued up the slot and made top hat spigots after I had taken the shots for posting.

You don't need full length bars, you can use round spigots, the same size as your slots (or top hat ones if the slots are different sizes) at either end of the vice slot, you could in fact put an extra one or two in for good luck if you really wanted to.

John

Yeah. The Kurt guys did a pretty good job on their grooves as they zeroed fine on the two I have, but I would be a lot more leery of some of the cast-in ones I've seen.

Carefully turned top-hats may be the way to go for people that don't want to mess with precise milling a bar or surface grinding it. They'd be a little more subject to wear, but that would be manageable and fairly easy to replace if needed.

Also people should check their T-slots actually are parallel with with the table travel and are consistent in width too. I've seen some I'd be doubtful of.

 

[Omnimill]

Right then, finally got round to milling up a lump of steel to fit the 14mm T slots on my Mill. Steel fitted in the slot I up-ended my vice and clamped it to the steel, now at this point I would have trued up the mounting slots in my vice but it doesn't have any ..... it has 13mm diameter holes instead. I've only done a very quick check but the holes seem spot on to the axis so I'm off to make some stepped buttons to fit. Even if its a couple of thou out (I could open up the holes) as long as I can nudge it true I'm sure it will cut loads of time off setting up the vice. I'll let you know ...

Vic.

Update: Well I made the parts and it's not quite as good as I hoped for but it's not too bad. I placed the vice on the table twice and both times it was .002" out. I quick tap with the hide mallet though and I can get it within .0005" which is what I normally aim for. It's sure to be a time saver so worth the effort I reckon.