New Updated CNC Bed Vise

My low profile CNC vise gets regular use,  It's only "flaws" are the limited opening, the slow movement of the jaw using a 3/8"-16tpi threaded shaft, and the moving jaw isn't attached to the shaft when backing out.  

This new vise design has a push button release for quick action, and a 19 inch opening for larger project boards. The jaws hold on to the shaft as it pulls back with a rare earth magnet. 

I made two bases using up-cycled 12mm thick baltic birch plywood with walnut veneer on the bottom side salvaged from an old coffee table top. 

Thickness of the jaws had to make room for the push button and conical spring below it. Button travel is close to 3/16" to push down an open 3/8" hole for the shaft threaded shaft. All vertical parts are a stack of assembled  layers. End jaw is two 12mm layers atop the 12mm base. The bottom layer that the shaft runs through is actually two 6mm layers.  Top 12mm layer on all pieces.  

Push Buttons

For the button I ordered a 3/4" diameter 12" length of aluminum rod to make the buttons from. The button shape was cut on the end with the aluminum rod clamped vertically. Next I clamped it horizontally and the CNC marked where to drill the 5/16"d hole and the bottom edge. My benchtop drill press cut the 5/16" hole.  I threaded the hole with a 3/8-16 tap with the rod held vertically in my bench vise. Then back on the CNC clamped horizontal to open up the 3/8" through-hole.  I hacksawed the button off the long aluminum rod, then put it back on the CNC to mill flat that rough end. It took a little filing and finagling to make the buttons slide easily.  

Button and Spring

I cut all the jaw and button end  parts from small pieces of 12mm and 6mm thick plywood. Alignment holes for 1/4" dowels were be added to each layer. 

The center hole for the threaded shaft needed to be perfectly placed. It was more precise to cut that center layer as halves from 6mm plywood.  A 3/8"d ball end bit cut the shaft slot in each. 

Rather than a stepped slide I chose a 14 degree dovetail slide. I used Teflon as the slide.  The center slot for the slide doesn't have to cut all the way through except in one spot where the slide can slip in to be attached to the jaw.  That spot was cut from the bottom side. Two flat head screws attach the Teflon to the moving jaw. 

Teflon Dovetailed Slides

The Teflon slides I cut at my router table with a 14 degree dovetail bit.  1.5" wide sections were cut from a longer strip. First test fit of each showed the slides were too wide.  I used my small hand plane to trim material off the edges until the slides slipped in and slid easily. 

Two 1.25" long flat head drywall screws attach the slides to the moving jaws. Action is smooth up and down the slot.  

The 1/4"d x 1" long rare earth magnets work to keep the sliding jaws attached to the threaded shafts.   

Rare Earth Magnets

Lastly sandpaper was glued to the face of the jaws for a much better grip on wood parts that are held in the vises.  Handles were CNC cut from a small scrap of dense white oak. 

White Oak Handles. 

These new vises will hold larger pieces of wood that will have the top surface carved/pocketed on them.   I can easily clamp the vises to my CNC bridges.

Comments encouraged!

4D