Snap.

That was decent Clarkson 1/2" endmill, and the first time I've broken one that big. Broken plenty of smaller cutters but not 1/2" sized. The problem was caused by this new machine vice (below) which simply won't grip/hold anything. I'm not sure why - maybe a combination of the very smooth/slippy jaw faces and also the poor geometry of the moving jaw (which is very tall compared to the position of the screw). I had it tightened up very firmly after having suffered slipping workpieces before with it, but it just failed to hold the part and that caused the breakage. If I can't think of a way of improving it then it will have to go because I simply can't trust it.

Chris, put a thick sheet of lead in the vise 3/8" or so and really tighten it up.

Then take the sheet out and measure at all 4 corners to see how it's holding as regards to tipping.

This will give you a starting point. On one of my vises I have a 5 thou shim behind the top of the moving jaw so in effect the moving jaw is tipped but when it's tight , it's parallel.

Forgot to add the lead sheet trick is SOP on punch presses to get the punch just tight.

Edited By John Stevenson on 05/05/2013 13:13:48

Very unsound looking geometry there. Can't see it ever working reliably with a conventional screw as the short moving jaw has very poor anti tip geometry. There are good reasons why the standard vice configuration has a long moving jaw despite the inherent space inefficiency. Best option if you don't scrap it would be a rebuild to incorporate pull down / anti tip geometry into the nut. Kurt are the well known exponents but most of the quality CNC vices have their own versions.

Somewhere on the net there is a good description of how the Kurt style system works with how to do a DIY equivalent details. Pretty sure I down loaded it but darned if I can recall where, or even if, I filed it. I rather fancy a smaller version of the Orange vice which uses a very similar base section and has an on-line parts list that appears to be well enough illustrated to permit successful "inspired-by" re-engineering and replication into a variant more suited to that size.

Clive

I don't have any suitable lead sheet, but I have put a hard steel parallel in and tightened up on that and it's easy to twist it in the jaws - clearly it is tipping quite a lot. I will try shimming the the top of the moving jaw until I can't easily twist the parallel, then I'l remove the jaws and rub them across a coarse diamond lap to roughen them up. However, I've lost confidence in it and will always worry whether it will hold...

Chris,

Send it back!

If you have to correct a new item yourself it is clearly not up to the required standard as defined in the Sale of Goods Act. I am sure the supplier will replace it of refund your money without any quibble as this is the way that most importers of Far Eastern products conduct their quality control. They supply items without any pre-sale checks and hope the customer puts up any faults or if they complain very quickly offer a replacement or refund. When this happens innocent purchasers who have parted with their hard earned cash are persuaded that the supplier has treated them very well and are very conscientious.

If enough people send faulty products back rather than put them right themselves hopefully these suppliers will eventually get the message and carry out proper quality control.

Send it back every time.

What a truly rubbish design, the screw should be above the bedways not below. The act of tightening will cause the jaw to rock backwards, send it back as suggested above. Trevor

Hi Chris.

Fine ground jaws in fact a nice finish all over. Is this a case of all that glitters? Something to watch out these days equipment that is tricked up, but not accurate.

Apart from on tiny toolmakers vices I would prefer a flattened diamond patterned grip face on the jaws, like on my old Abwood. Two of my machine vices have this the other has small v grooves about 3mm deep about 8mm apart. A shiny face has very little friction to hold the part. If I want to protect the work a box of assorted aluminium and brass strips of the right length is always to hand to slip in between the work and the jaws, sometimes I use paper.

The movable back jaw? Is it really necessary? I noticed the V in the back of the jaw after you turn it around for holding vertical work. that can be replaced by a slip in piece with a V milled in it, a couple of those live in the same box as the strips.

The diagonally disposed set screws that hold the back jaw in place are intriguing? there must be an uneven resistance to the clamping pressure of the opposing jaw, at a guess the jaw would be more inclined to lift on the side where the screw is towards the back.?

I also would be inclined to credit it.

Your work moving reminds me of a nasty accident that happened in a shop nearby, a person who should have known better was in a hurry and set a 3 jaw chuck on a rather large Dean Smith and Grace lathe. No not on the spindle register, clamped in the jaws of the 4 jaw already there, it was a big one and had to be craned off. I guess you know what came next. hard steel on hard steel = very little grip as soon as he started up a hundred pounds of spinning iron flew across the room doing considerable damage including injuring the operator.

Cheers

John

Two bolts and two dowels locate the fixed jaw. It appears to clamp down securely when tightened down firmly, and I don't have a problem with that. It can also be repositioned in one of three places relative to the moving jaw to acommodate workpieces of different width - one of the features I found attractive. It is supposedly a British design made abroad. It is made well but I feel the design has fundemental faults (which to be fair I should have spotted at the outset). http://www.warco.co.uk/vices--vice-jaws/110-dh-4-precision-vice.html

As stated, the position of the screw is too low:

The rear of the vice is prone to filling with swarf so I made a cover for the gap:

Apart from the fact it doesn't work as a vice I was quite pleased with it...

If you think the shiny jaws arent helping have you tried a slip if paper around the work?

Paul

Full patent is here (you will need to enter a number).

The moving jaw allows a shorter clamping screw, but the compact design requires the short bearing surfaces and for it to be belown the ways of the vice.

I must admit, I'm not 100% convinced jaw lift is the whole problem. How great is the clamping forcec compared to another vice? (Squash two bits of 6mm aluminium rod by the same amount and compare the force needed to get teh same amount of squish)

Eeek! Just seen price...

Neil

An alternative solution would be to have one jaw with a central extension moving between two long extensions of the other jaw. The extensions pass under the opposing jaws as well as bearing on slideways in the base.

Dang! Now I can't patent that!

Edited By Stub Mandrel on 05/05/2013 17:48:28

Edited By Stub Mandrel on 05/05/2013 17:52:13

Just because something is patented doesn't mean it will work as promised. And that won't. The screw arrangement is fundamentally pro tilt and the thin sheet guides under the square guide ways are grossly inadequate to hold the jaw down.

I have a pair of Vertex 4" jaw width vices with similar, albeit much more robust, guide arrangements with the moving jaw something over 6" long. Mine have a pin and through hole arrangement to locate the feed nut enabling 3 opening ranges to be selected with a maximum of 8". The wide range is handy but its essential to keep an eye on the relative positions of moving jaw and base being prepared to deal with lift and/or tilt issues in the out third or so of the opening range as the moving jaw extends beyond the base by some 3" at maximum opening. Its never been a big problem for me and certainly up to around 6 inches or so of opening jaw lift / tilt is no more an issue than with any well made vice. On the rare occasions when I need the maximum opening I'm prepared to work a bit harder simply for the convenience of a wide opening vice that I can actually lift!

If there is sufficient metal in the body to put a second set of grooves inside it could be made to work reliably by adopting a system similar to that used by Orange Vice Company. They arrange the feed screw to operate in tension and drive the moving jaw from a sliding block running in a slot beneath the top surface of the vice. The drive block and jaw connect via a pair of interlocking wedged teeth acting to pull them together as the vice is tightened up thus actively preventing jaw lift and tilt. When tight the top jaw and block sandwich part of the vice body between them so things shouldn't move. The Orange Vice website is here, look at the specification section and parts diagram A will show you how they do it. Some pretty subtle engineering involved.

Clive

Thanks, got the PDF now... I couldn't find it with a search

The vice is supplied with two handles - one with a short throw and one with a long throw for better leverage. The short one is necessary because the long one cannot be rotated fully without hitting something.

I'm considering a cunning plan but it would mean altering the vice, an irreversible machining operation so I might drop Warco a line first to explain my position. As Neil noted - it wasn't a cheap vice.

As others have said its a flawed design. I would certainly try and get a refund or exchanged for something that is usable.

To me, the diagonal positioning of the fixed jaw bolts is plain illogical. Two bolts and two dowels are fine, but what sort of reasoning decides that one of the bolts should be in a less effective position. If the bolts were only subject to shear loads only, or the jaw had to resist loading from the rear then I could accept it, but in this case it make no sense.

I have just seen what looks like a small step on the back of the fixed jaw, which make me think it reversible. If it is, then using dowels is a bit suspect. I thought the whole idea of dowels is to drill and ream in one position, for this vice they must do all the dowel holes by dead reckoning, or just fudge them.

Ian P

I seem to recall that this vice was given an excellent review in either ME or MEW or am I mistaken?

Tony

The Orange Vise site has a nice Speed/Feed calculator and a Drill/Tap chart the page is at

**LINK**

Brian

You could use two bits of soft solder wire about 1 or 2mm diameter, run them down the face of the parallel at each side then compare thicknesses of the solder after tightening up the vice and letting it go again. (That is the way we set presses here in the sticks where lead sheet is a luxury.)

Why make compromises with a brand new expensive bit of kit send it back and say not up to standard and not suitable for purpose intended. End of story want my money back...

Bob

Most people seem to get lead sheet for free these days. I spoke to a guy who had an office near ours and they had lost the lead of their roof four times in as many years - grade 2 listed so it has to be replaced!

Neil

Neil

You cant have a very high opinion of society if you think 'most people' get lead by stealing it!

IanP

Metal roofs don't last long in the West Midlands. I know one War Memorial that lost its copper roof so many times they've had to cover it wioth a green 'look-alike' material.

We've even had non-lead flashing tape stolen off the roof of one of our buildings, so I fear some idiot will try and weigh in the fake copper..

Sadly the souncdrels aren't metalurgists

Neil