Roller Fail

So my CNC roller works really well. Except I pulled a bonehead and used a piece of cardboard for the roller. 🙂

I’ll make another one out of PVC since I have some pipe lying around.

That plus the 1/4″ shaft should work for a while.

Sheet material hold down on CNC


In ongoing issue with cutting cardboard is that it tends to be fairly floppy. You can clamp down its edges but the center often bulges away from the table.

Of course you can lord over the machine and help hold the material down.

This problem happens when cutting a larger piece of hardboard as well. The endmill sometimes tries to lift the material up as it’s pulling material away from it.

I thought of adding a small wheel to the cnc machine that can press down on the material being cut. So when the endmill plunges down, there will also be a wheel that comes down on the material.

I thought it should be spring loaded and that it should be a castor so it will follow the direction of the cut.

It may not be clear from the diagrams but I need to add some 1/4-20 threaded rod. Two pieces to form the axle for the wheel and the lever axis. Another vertical in the Square hole. A spring is running from the small holes at the lower right to the hole at the top right.

I cooked this quick design up in Sketchup and will cut it out shortly and see if it works.