Tube Clamp Jaws

thingiverse

Here's how you get a firm grip on tubing or axle: Use pliers or pipe vise and unwanted marks appear on the surface. A simple tool helps a lot in situations like this one. I have used aluminum blocks of this type but they're hard to make. Two M3 20mm countersunk flat head screws serve as locating pins. The mating pin holes are reamed with a ø3mm drill bit if necessary. UPDATE: I made another set of jaws for 12-15-16-18-20mm tubes. A deeper increase requires M3 25mm screws as locating pins. There's dimensional drawings to help make customized versions.