Quick release vices

[Dieselman 63]

There is a big Record 25 at uni with a quick release lever disengaged. I asked why, and was told that any qr mechanism can disengage with enough force from the tommy bar. Surely this can’t be true since the only way it could disengage would be if the lever was pushed?

 

[PhillipM]

If they're knackered, yes, but we had a big record QR that got all sorts of abuse on the bar and never budged.

They don't seem to have much issue with half nuts on lathes either...

 

[MattF]

It usually only skips if the spring tension is set too low. The design of the buttress thread on the QR vices actually draws the screw and nut in more tightly to each other, when under pressure.

 

[pedrobedro]

I have to turn my vice handle out half a turn after using the quick release to get it to engage so it will lock up again. It holds firm though.

 

[Dieselman 63]

It usually only skips if the spring tension is set too low. The design of the buttress thread on the QR vices actually draws the screw and nut in more tightly to each other, when under pressure.

That’s what I thought, with the buttress thread.

I recently cleaned one and they offered to pack it with grease for me...