CNC Low Profile Pull Down Side Clamp

Low profile pull down clamp for fixing a workpiece from the side on a (cnc) machine/router.

This is helpful for facing operations where the toolpath covers or extends the area of the workpiece and any clamping from the top would be in the way.

It is a print-in-place, meaning the two pieces are interlocked with a gap of 0.3mm (alternatively 0.5mm) so they are still moveable. This way the parts are as stiff possible. 

For me the 0.3mm gap works fine when printing PLA. I tried printing ABS, here the 0.3mm where a little tight - I had to use a vice to free them… 

So you will find two gap options: 0.3mm and 0.5mm.

There is also the option to leave room for a washer. This is helpful when using a T-Nut table. I figured that this prevents the clamp from slipping when tightening the workpiece. When directly mounting the clamp to a spoilboard there is probably no need for the washer.

Dimensions:

• 14mm height
• 2mm travel

Printing:

• Enough wall loops to have the clamping part filled - I used 6
• Upright orientation
• Supports for clamp part, other than that: no supports - see pictures

Additional hardware needed:

• 2 x M4 x 14mm screws
• 2 x M4 nuts

Optional:

• 1 x M6 screw (and a T-Nut if mounted on a T-Nut table)
• 1 x washer (1.2mm thickness, M6 hole, up to 20mm diameter)

Assembly:

Put the M4 nuts in the predefined notch - this is a bit fiddly since they are slightly angled. You might need some pliers to squeeze them in place.
 

Options:

For certain scenarios a slightly grippier clamp surface might be helpful. I used fuzzy skin for that (point distance and thickness 0.1mm)