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View Full Version : Yet ANOTHER leg vise question



Zach England
12-23-2011, 9:43 AM
I have decided I want a bench with three vises--a wagon vise, a twin-screw and a leg vise. My reason for this is because I think it will make the best of my space limitations. My bench will be shorter than most (probably 5 feet), so I am mounting the twin-screw on the end. as not to take up too much of the face area.


My current bench has tail vise, which I will use for the wagon vise, and this (http://www.leevalley.com/us/wood/page.aspx?p=31137&cat=1,41659,41661&ap=1) as a face vise.

I am wondering if there is a compelling reason to not re-use the face vise for the leg vise. I am basically thinking of turning the face vise vertically, taking advantage of the alignment rods to prevent the vise from racking. I would then mount another board on the end of the bench to accommodate the guide assembly. I don't need to have much horizontal space with the leg vise since I have the twin-screw.

Does this even make sense? I may need to sketchup a diagram.


Thoughts?

Thanks, as always.

Chris Griggs
12-23-2011, 10:39 AM
I get what your saying, but my one concern would be this. A leg vise uses racking to get it's power. The pin and parallel guide are set to the same width or just a bit wider than the piece being clamped so they cause the top of the chop to rack into the work piece. Turning the face vise side ways you would prevent some of the unwanted racking, but you also wouldn't get the racking in the direction you want it, if that makes sense. It might work, but I think you might not get sufficient clamping pressure.

Zach England
12-23-2011, 1:20 PM
That makes sense. Thanks. Look for a face vise in the classifieds section in the coming weeks.

Mike Holbrook
12-24-2011, 12:17 AM
Zach,

Have you thought about using a Moxon instead of the twin screw? I think the Moxon will do the same work as the twin screw but place your work at a better height for most of the work this vise will do. The removable vise will also leave much more of a small bench available for clamping. I'm going to make a Moxon with Benchcrafted's Moxon Hardware which adjusts very easily for a twin screw. There is a great video about the Moxon with Benchcrafted Hardware at Benchcrafted's web site.

Zach England
12-24-2011, 9:37 AM
Zach,

Have you thought about using a Moxon instead of the twin screw? I think the Moxon will do the same work as the twin screw but place your work at a better height for most of the work this vise will do. The removable vise will also leave much more of a small bench available for clamping. I'm going to make a Moxon with Benchcrafted's Moxon Hardware which adjusts very easily for a twin screw. There is a great video about the Moxon with Benchcrafted Hardware at Benchcrafted's web site.


I have thought about this, but have decided against it. Height is not really a concern for me because I do most of me end-grain work sitting down on an adjustable stool. I also want the twin-screw for working on the edges of medium-length boards, much in the same way I use my face vise now. I am going to mount the twin-screw on the end of the bench so there will be a vise on each of three sides. I know it's less than traditional.

Mike Holbrook
12-24-2011, 10:41 AM
Good points Zach. I am finishing up 4 Purple Heart planes that are taller than metal planes. I also have a tall Blum Fore Plane. I am making a new bench that will be at a lower height to allow me to better use my taller planes. The Moxon's height in this situation will be of greater advantage than in your situation. I am designing my new bench to work at multiple heights. Along with the Moxon I will make the additional table Derek Cohen came up with as a companion piece. I will end up with something like a bench on bench.

I just ordered the Lee Valley screw, listed as for a tail vise, it is very popular for making a leg vise as well. It sells for only around $35 and LV is currently offering free shipping. Now all I have to do is figure out if I want to angle my leg vise like Chris did or maybe just make it bigger. I am a little confused about the racking though. This is the tendency of the leg jaw to pinch work at the top as the bottom is pulled in by the screw? I can see how two vertical or even horizontal screws might prevent this action. Would this mean that one can use a wider and or angled jaw without quite as much problem with the jaws "racking" side to side?

Jim Koepke
12-24-2011, 1:34 PM
I can see how two vertical or even horizontal screws might prevent this action. Would this mean that one can use a wider and or angled jaw without quite as much problem with the jaws "racking" side to side?

The racking of a leg vise is two fold. The vertical racking is controlled by the lower rack and pin assembly. The side to side racking is where one has to use shims and spacers to control.

Having the leg vise slanted allows for clamping items in one side of the vise and crossing the center line of the vise to minimize the side to side racking.

A slanted leg vise also helps to lessen the racking of the bench when planing long boards.

jtk