Extending the capacity of a machine vice

[philf]

I've often needed to hold a piece of material which is much wider than the capacity of my machine vice (Abwood 4" which has a capacity of about 70mm).

Some times this is just to square off a piece of plate but it means I have to remove the vice, clamp the piece to the table, do the job (which may take a couple of minutes) then put the vice back on and square it up.

It occurred to me last week that I could double the capacity of my vice for light machining very simply.

When I made new jaws for the vice I made them so that they stand 3mm higher than the body of the vice.

I had some 25 X 3mm gauge plate and I cut a length to match the width of the vice jaws. With the gauge plate on parallels in the vice I drilled 3 off 5.2mm dia. holes for the clamping screws and drilled and reamed 2 off 5 dia. holes for dowels. I then repeated this in the moving slide of the vice except the three 5.2 holes were drilled 4.2 and tapped M5.







So for a few minutes work I should save myself hours in the future.

The holes in the moving slide are positioned so I have a slight overlap in capacity. I could still machine another set of holes to further increase the capacity but I'm already about at the limit of my Y travel.

I am leaving the extra jaw in place as it doesn't get in the way and all I have to do to use it is to remove the moving jaw.

It works very well and has already saved me the time the job took to do.

It may not work so nicely on all types of machine vice.

Hope it was of interest and the idea may be useful to someone else.

Please don't do the mod to yours and then proceed to mill away much of the vice forgetting that underneath the part isn't fresh air!

Phil.

[Stilldrillin]

Phil.
That's a bit clever! 

Well done! 

David D

[philf]

Thanks David,

But I really ought to be making things other than tools!

The piece of material in the vice is a piece of gauge plate I bought at Harrogate last year for my loco and I've only just today been doing some layouts so I can get eight valve gear parts out of the one piece on the CNC.

Cheers.

Phil.

[Meldonmech]

Hi Phil
               
          Thanks for the tip, I have exactly the same vice and have similar problems. I regularly remove the moving jaw to get that extra bit of capacity. I find removing the vice such a bind these days, and it always seems to happen when I am in the middle of a job.
                               Must find time to do the mod.
                                                                                 Cheers David

[BaronJ]

Interesting concept.  I would imaging very adaptable to suit most clamping devices.  Certainly ideal for flat plate.
One thought though.  How much would jaw lift affect the work piece ?  Particularly if you needed parallel surfaces.


 

[philf]

Interesting concept.  I would imaging very adaptable to suit most clamping devices.  Certainly ideal for flat plate.
One thought though.  How much would jaw lift affect the work piece ?  Particularly if you needed parallel surfaces.

Hi Baron,

I don't expect it to be dead parallel but for squaring off ends or spotting hole positions it's fine.

The vice is pretty good having a dovetail slide which, if set on the tight side, doesn't exhibit much jaw lift but if you are trying to machine something dead parallel then the mill is probably not the right machine.

Cheers.

Phil.

[BaronJ]

Hi Phil,

Unfortunately my mill vice is an ancient "Record 414" that I bought some 40 years ago.     It had various bits of surgery in the intervening years.  Whilst a perfectly good vice it has about 1 mm of play under the moving jaw.  I did try to rectify this by fitting 1 mm thick Mylar sheet underneath but it makes the jaw very hard to move, particularly when unclamping the work piece.

But I do like your idea.  I hate the thought of marking machine tables when machining.

[philf]

I see Arceurotrade are now selling "ARC Versatile Milling Vices" which have used the same idea for extending the capacity of a machine vice. They have expanded on it by giving a few more possible positions for the jaws.

http://www.arceurotrade.co.uk/Catalogue/Workholding/Machine-Vices#ARC-Versatile-Milling-Vices-with-swivel-base

Phil.

[John Stevenson]

Hardly your idea  Phil   

Been around for years, my small Abwood was converted years ago and we had already been to the factory in China to talk about the designs and mods the previous year from your initial post.

Still a good doge though.



This is the large one positioned on the table to match the fixed jaw on a 6" Abwood and fitted with an alternative set of jaws with vee grooves in [ at present not in stock, this is one of the prototype vises ]



Bit of a shaky camera phone pic but this one shows the small 100mm swivel with extended jaw openings.

Actually down there today picking a couple more of the 100mm ones up and they are nearly sold out.

[philf]

Hi John,

I've reworded my post slightly.

I had never seen it done before so the mod to my vice was entirely my idea!

I wasn't trying to infer that Arceuro had pinched the idea I just thought the vices looked very useful.

As is pointed out you wouldn't want to do any heavy milling in the alternative positions.

A question - I like the idea that the moving jaw is forced downwards but are both ends of the screw anchored? I would think that there would be a tendency to lift the screw. (Or does the nut run in a guide which prevents lift?)

Cheers.

Phil.

[Stilldrillin]

I promised myself a more versatile vice, ages ago.......

Just ordered 100mm one! 

David D

[John Stevenson]

Phil,

No problems, not having a punt.

The nut runs in two long slots, one on either side to stop lift and the nut on the 100mm ones is about 50mm long without going to look. Personally I think the factory has made a good job and not just saying this as i have seen and bought some crap in my time.

As regards coming up with the idea, been there, done that. 

Few years ago came up with the idea for a steady where everything was mounted inside a large thin section bearing so it could clamp onto rough, welded or irregular shafts and run supported at speed.

Built one and posted it over on HSM forum only to find out I had re-invented the Cathead steady from over 100 years ago.

It was like deja vu all over again. 

[DavidA]

Phil,

Like the idea. One thing I would like to suggest is that you mill a small ledge on the fixed jaw so that there is no tendency for the job to be pushed down.

Dave.

[philf]

Hi David,

A very good idea but I'd rather make a parallel of the right height so I can leave the jaw as standard.

A job for this evening!

[Now done.]

Cheers

Phil.

[Stilldrillin]

I promised myself a more versatile vice, ages ago.......

Just ordered 100mm one! 

David D

And..... Yer tiz! 




Blummin HEAVY, and a little overwhelming, for a mini mill. But, not bought as the main vice, just for the larger projects.

Will strip, and commission, over the next few days. 

David D

[awemawson]

  Nice  and very tempting - how do you rate the build quality?

[Stilldrillin]

Nice  and very tempting - how do you rate the build quality?

Merely lifted it onto the mill. No further exploration, today.

BUT...... The handle hexagon drive, is around 60thou larger a/f, than the screw hexagon! Rather a baggy fit....... 

David D

[Stilldrillin]

BUT...... The handle hexagon drive, is around 60thou larger a/f, than the screw hexagon! Rather a baggy fit....... 

I rang Arc. Hoping they had supplied a 125mm sized handle.

Ian had a look at a stock example. "Just the same"....... Seems, that's how they come! 

They have supplied 30, or so. I'm the first one to mention it.

Guess I'm too picky......

David D