Vertex VA4 Vice lift

[picclock]

Hi
I have a VA4 which suffers from lift as the jaws close. The VA4 is a clone of the Kurt vice with the holdown, which clearly isn't holding down. I read a post on this board (I think it was this one) where someone stripped his VA4 and modified it with two orings to cure the lift problem.

I have yet to strip mine down as I'm too busy doing stuff, but I can't go on clobbering things so I guess I'll have to.

Has anyone else resolved this issue ?. Does anyone know what happened to the original post? It was some time ago so it may have just disappeared (or, heaven forbid, it may be on a competing forum - oops!).

Any info or advice on stripping the vice most welcome.

Best Regards

picclock

 

[picclock]

Since my last post I have stripped down the vice and resolved the issue. The first mistake I made was to remove the backstop and unscrew the whole assembly. With hind sight this was quite unnecessary. To remove the movable vice jaw its just necessary to unscrew the centre grub screw(s) (one locking the other an adjuster) at the back of the moving jaw. The jaw can then be moved forward and unhooked from the shoe. There is a half round ball bearing trapped between the two.

It was evident from the witness marks on the shoe that the top of the shoe was inserted into the upper jaw as far as it could go. This resulted in the minimum gap between the shoe and upper jaw being greater than that of the base, hence the lift of the jaw when tightened. Removal of the casting flash/burr from the shoe allowed further engagement reducing the gap and allowing the pull-down mechanism to function perfectly again.

The problem was caused by the wear and deforming of the round bearing. When purchased it worked OK, but over time the hold down problem became worse to the point where it had to be resolved. A more permanent solution would be to use a 16mm ball bearing with part of it ground flat (or possibly a 16mm dia dimple put in the shoe).

Any donations of 16mm Ball bearings welcome ;D

Hope this may help someone with a similar issue on their Vertex VA4 vice.

Best Regards

picclock

 

[Omnimill]

http://www.ebay.co.uk/itm/ONE-HIGH-...ols_Levels&hash=item336e96ea27#ht_1008wt_1198

Shame about the postage!

Glad you've sorted the problem.

 

[f350ca]

I have a similar vice. I think it needs the half ball to slide on the shoe to create the downward force. Dimpling the shoe and using a full ball would lock the shoe to the jaw.
Wonder if a brass ball would slide beter on the shoe? Might be too soft though and deform over time.
Greg

 

[picclock]

@f350ca

Your quite correct of course. I would have to grind a flat on one side of the bearing. I don't think the original one can be very hard to form the indentations and wear I saw on it. But the pull down is very strong now and quite impressive. I think possibly better than when it was new. I just wonder how long it will last before I am forced to take further remedial action.

Best Regards

picclock