Myford Vice for Vertical Slide

If it's any help ... the one illustrated here seems to be the real deal: **LINK**

https://m.youtube.com/watch?v=AQwFH3k3QTk

It's engraved with name and part number on the top of the fixed jaw [pause video at 0:16]

Of course, the usual caveat will apply [continuous product development, blah, blah]

MichaelG.

I can't imagine how a plausible stress concentration would compromise accuracy more than the indeterminate datum Mike's suffering from.

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I think John's point was that cracks start where stress is concentrated !!

MichaelG.

Mike Donnerstag - just curious - are there any tapped holes or through holes in the fixed jaw with the radius? f there were, maybe the vise was supposed to have a ground jaw insert plate wider than the jaw base radius. This would allow the vise to have a stress relief radius but still hold work square / not rise up so much. The radius on your vise is unusual - I have only seen it on vises from the far east made with low strength iron. Hope this is not the case with yours. Clamp up some steel and take a good heavy cut, and see!

Anybody seen a vice cracked there, ever?!

I've seen some deeply abused vices, especially in subcontract machine shops, but never a crack at the base of the fixed jaw.

Image from Here

I don’t know how ‘original’ that vise might be. Could have been cast in some back yard in India. I would expect subcontract machine shops would have far better vises to start with - not a myford hobby exhibit.

Likely, too, that any hard-worked commercial vise has replaceable jaws?

I suspect it is not a vise from the 70s or before. Myford quality started(?) to go downhill when they imported from asia? Cheap and cheerful, I would suggest. Cheap casting, minimum machining and no replacable wearing parts. Give me an Abwood any day (probably now sourced from the far east but built robustly).

QED.

Gordon Bennett - never seen owt like that before. Can't see either radius or undercut in that corner.

I still think a radius raises some 'fitness for purpose' issues. I've never noticed one on any vice I've used, and if I ever buy another, I'll make sure it's like my current one and allows datuming off a square-cornered flat located against fixed jaw and vice floor.

They might have been better to start with, but some I've seen had had the handgrip hammered off the handle, and the 'replaceable' inserts - or for that matter the whole vice - looked as if they'd been chewed by a steel dog with carbide teeth. This was in the 70s - there were very many workshops being run hard on a shoestring with knackered kit even then.

Back in the 70s? Unlikely that those items would have been cast in a back yard foundry like many are these days!

Michael Gilligan: Mine has the engraving of the Myford name and part number too.

Jeff Dayman: The fixed jaw has no holes drilled at all, though there's nothing to stop me from drilling it for fitting false jaws, though I'm worried a little about the resulting accuracy.

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Thanks for the confirmation, Mike

May I repeat my suggestion that you attach a false jaw [maybe made from gauge plate] with magnets.

MichaelG.

If you use gauge plate as Michael suggests, that would probably solve the whole issue with no loss of accuracy - though my preference would be to avoid magnets and use socket head countersunk screws in the jaw insert, possibly with clearance holes in the fixed jaw, nutted onto a spotface on the outside. That way you can set the top edge of the gauge plate insert parallel to the floor of the vice and tighten it there - though you might have other ways to achieve the same result.

An alternative daft suggestion, to retain the maximum jaw opening, and hopefully, avoid a stress raiser.

Clamp a sacrificial piece in the vice, (Radius the edge if you like, to match that on the fixed jaw ) and then drill a small hole through the intersection. The radius removes the "arris", and undercuts the jaw without making a stress raiser

There will be a minimal loss of strength, since metal has been removed, but probably not enough to cause real concern.

Howard

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Perhaps the radiused corner was 'cleaned-up' by some well-intentioned 'previous owner'

MichaelG.

My vice is a genuine (Beeston) Myford item, I bought it in the early 1970s. It has the radius at the foot of the fixed jaw.

I use it with a packing piece, a length of 5/16" diameter rod with a flat machined along its length, but a bit of flat strip would do. I usually grip a steel rule in the jaws, on the packing piece, and offer the rule up to the face-plate (fitted temporarily) before tightening the securing bolts that attach the vertical slide to the cross-slide. It works for me.

Best regards,

Swarf, Mostly!

I've had two vices have the fixed jaw pop off. One was a cheap angle vice which had a massive blowhole in the casting, the other was a middle-quality vice, but its lever-camlock design allowed far too much force to be put through it.

Neil

Another view of my vice, showing the part number:

Looking at that pic, I'd want to make up two strips of steel flat with suitable holes spaced for those mounting slots. I think washers would force the t-bolts too far out for comfort.

Ah, I see Alan Vos suggested something similar...

Edited By Mick B1 on 15/07/2019 16:42:40