# Quick release woodworking vise question



## shampeon (Jun 3, 2012)

I got a deal on an American Scale Co. No. 203 quick-release woodworking vise (nice and big and heavy) at the flea market the other day, and I'm trying to figure out if what it's doing is a bug or a feature.

One side of the screw has no threads, so when you turn counter-clockwise a turn the bronze quick release nut disengages the screw and the rear jaw is free. When you turn it clockwise to tighten, though, it goes about 3/4 of a turn after the threads re-engage before locking up. Is this how it's supposed to work? My Columbian quick release vise allows you to completely tighten the vise, but will disengage the nut when backing up a turn.

I disassembled the quick release nut housing, cleaned out all the accumulated gunk, filed down one a small section on the side that got distorted, and reset the spring on the nut, but it's still happening. Pictures to follow.


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## shampeon (Jun 3, 2012)

Any ideas?


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## TheCook (Aug 5, 2012)

That seems weird to me. Both of my quick release vises unlock with something like a half turn counter clockwise and will turn all the way closed by spinning the handle clockwise. From your picture it doesn't look like the locking mechanism can be installed backwards so that rules out my first guess…


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## WoodKutter (Nov 27, 2008)

Looks like it is supposed to work that way. On my Colombian quick release vise the nut floats. When you turn the handle CW it engages the the nut with the lead. when turned CCW it disengages with the screw. On yours the nut appears to be in a fixed position. The flat on the screw is where it disengages from the screw. 3/4 turn CW and you're tight.

Gary


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## Sylvain (Jul 23, 2011)

The cover piece hiding behind the top rod on your picture does not seem to be symetrical.
So there seems to be two way to put it back.
You could experiment with this.


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## shampeon (Jun 3, 2012)

TheCook: yeah, I assumed that that's how all quick release vises work.

Woodcutter: the bronze nut actually does float. You can see the spring that holds it flush against the right side of the housing.

Sylvain: I'll try flipping the cover around.


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## shampeon (Jun 3, 2012)

Well, mystery solved, I guess. The nut wasn't the issue. There's a tab on the handle casting that prevents the handle from rotating. So I think it's just supposed to tighten down 3/4 of a turn max. Strange.


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## TheCook (Aug 5, 2012)

That's really bizarre.


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## TopamaxSurvivor (May 2, 2008)

From the looks of the pics, if it went all the way around, it would disengage when it hit the 360 degree mark. There is a plus, you can't squeeze your wood too tight ;-)


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## OnlyJustME (Nov 22, 2011)

I have a quick release vice that works the same way but it isn't a traditional looking vice with threaded rod. it has a saw tooth flat bar that engages to tighten on the work. the vice should still get plenty of clamping power in 3/4 turn. mine does. i'll post some pics of it tomorrow.


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## MNgary (Oct 13, 2011)

If it works, don't fix it.


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## Sylvain (Jul 23, 2011)

As the nut is only 1/4 of a turn and as the screw has thread only on 3/4 of a turn, obviously if you turn more than 3/4 the screw would disengage again.

It is a bit like some thread used on canon :
http://en.wikipedia.org/wiki/Interrupted_screw
http://en.wikipedia.org/wiki/Rifled_breech_loader


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