Anatomy of a Leg Vise

vise5Here is the leg vise I built for my bench. These aren’t “off the self” items like bench vises so I figured I’d document mine. I made mine for $7 as I had most of the materials in my junk piles. I got the 3/4” x 5tpi Acme screw from my local scrap yard (Burcham’s Metals) for 80 cents and the nut from MSC ($6). The vise screw clamps the vise face (or “chop”) to the bench leg and the “foot” of the chop is the other end of the fulcrum.vice2

My chop measures 26” tall x 2 1/2” thick x 7 1/2” wide. The screw is 8” from the top. Bench Crafted recommends 8” – 9”and around a 1 : 3 ratio for chop length to screw. I choose 8” because any lower and I’d have to bend over too far to adjust the vise (the bench top is kinda low at 33 1/2”).

The screw and foot are 13 1/2” long (11” in front of the chop). Not including the knob. The vise opens to 7 1/2”, about the same as my Record bench vise.

Performance
I would liken it to a Stanley Bailey plane: it works, I like using it but it won’t get me to say “wow!” (unlike a Bench Crafted Glide). In contrast, I really dislike my Record 52 bench vise.

vice screwThe Screw
The handle is a chunk of 7/8” broom stick with two caps to keep it on the knob. One cap is glued on and the other screwed. The knob was turned from a piece of 2” steel rod and brazed to the end of the screw. A steel collar (with set screw) acts as a garter to retract the chop. A plastic washer keeps things smooth and quiet. The set screw (5mm x 0.80) just almost fits between the threads so it jams nicely. A split collar works “better” but is too big for my tastes.

vice nutThe nut is mortised into the bench leg and held in place by a wood plate.

vise face plateThe chop has a decorative face plate that acts as a washer and spacer for the knob.

_

_

The Foot
vise toeThe bottom of the chop is the depth stop and, in this case, supports the chop. I made it out of maple and mortised it into the spruce chop. Miller dowels add some peace of mind as this chop seems really wimpy (the tree fell down in my front yard).

A 3/8” steel pin is the depth stop.

The foot rides on rollers. This is a innovation that Bench Crafted introduced with their Glide vise. Otherwise, the chop hangs vice rollerson the screw and/or slides on the foot mortise, which can lead to binding and isn’t very free running. I like the look of small rollers, even though bigger ones work better. My original plan was to use fixed casters but I couldn’t find any cheap ones. Then I tried small rubber rollers but they deformed enough that the foot would bind in the mortise. So I replaced them with wood and they are working dandy. The roller bracket was cut from 1” square tubing. A slot is cut for a lag screw and a hole tapped for a 1/4” x 20 screw. The slot allows you to fine adjust the screw height to align it with the nut. Both sides are tapped, which I think is both unnecessary and will keep the sides from deforming. The 7/8” dowel rides on a 3/8” steel bushing.

If you have looked at the Bench Crafted parts, you will have noticed the black plastic plate that is mounted to the front of the bench leg. The hole in the leg is bored a bit oversize so the screw doesn’t bind and the plate is a screw guide to remove the resulting slop. I don’t use the plate and, as a result, the chop flops (side to side) as it moves in and out. It doesn’t bug (yet) but might if I had a hand wheel.

Notes:
As the vise tightens, it tips forward (at the top), pivoting at the pin. This means the foot tips down (unloading the top roller) so I think it is a good idea to leave a bit of space under the foot. Otherwise, if the foot presses down on something, it puts pressure on the foot/chop joint (which is bad because of the leverage). My foot can drop about 1/4” at the toe.

Advertisements
This entry was posted in Benches & things to sit on. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s