B&D Workmate Update for my CNC Bridges

Bridge Vise for Vertical Clamping

The Black and Decker Workmate is an ingenious product.  The split top serves as vise jaws along with the bench dogs to allow clamping boards of most shapes snuggly to work on. I've owned one for 4+ decades and found many uses for it. 

On my CNC I use 3 bridges rather than a t-slot or vacuum bed to hold boards in place. T-track in each bridge top let me slide wood clamps to hold down projects.  I woke up early on 2/27/2026 with the idea of modifying two of the bridges so I can also use them as clamp jaws.  (Bridges)

First step was to double up the thickness of the jaw faces. I glued another piece of 18mm Baltic Birch plywood to them to create more surface area on the mating faces. I then applied some Cat's Paw friction tape to their surfaces. 

Doubled Up

There is roughly 22" between the right side rail and the radial axis tailstock rail.  Swing room for the crank handles may eat up 1.5" on each side.

The bridges don't need to open more then 1.5" or so for what they may need to clamp vertically.  Short lengths of all-thread, a couple lock collars and Teflon washers on each side, and a couple handles.  I'm using 7/16-14 all thread.  My local True Value store had 2' lengths of 7/16-14 all thread. I bought one and cut two 9" sections from it for this project

Some blocking to bring the thread collar out flush with the edge was added.  Collars and square nuts were ordered from the Jungle store. 

Collars arrived 3/11/2026.  I drilled a recess for the collars and the Teflon washer on the inside of the front bridge using a 1.25" Forstner bit on my Nova Voyager drill press. 

I made the Teflon washers for the 7/16" all thread. I clamped down a 1/16" thick sheet of Teflon on my CNC to cut the center holes that will ease the process.  I sliced off the row, then snipped them apart before sliding them onto the all thread.   I clamped them in place with a hex nut on each side, then mounted them on my hobby lathe to turn them round.  

3/16/2026: I finished up this project this day.  I chiseled out a slot for the square nut to be able to slide under the top of the bridge, then glued a board next to the nuts so they wouldn't be able to turn when tightened down. To keep the nuts in place I added magnets next to the shafts

Square Nut. Round Magnet

First test holding a 3/4" thick section of plywood proves they work.  As with the Workmate though the pressure from each side needs to be the same for flat boards.  Best strategy is to make sure the front side is parallel to the front frame rail and locked tight to the side rails. Screw the back bridge/jaw tight, then lock it tight to the side rails.  

Handles were needed.  I drew up a design and cut them out on my CNC from a thick scrap of red oak.

Red Oak Handle

Two Hex Nuts Jammed Together

Handle slips over the outer hex nut.

This idea works well for holding boards vertically to CNC joinery on their end. Dovetails and box joints and variations are now fairly easy to cut using my CNC.  The details of this project are prototype solutions.  As I use it needed improvements will like show up. I'll append them to this blog post when/if they happen. 

4D