Many years ago I made this 12"  dia embroidery hoop. To use it, set it between your legs using your leg weight to hold it in place. It has 3 adjustable joints and three finger bolts to hold it in place. Over the years the friction hold points of the adjustments have become too smooth and it slips. If I roughen up the friction hold points, they will soon be smooth again.

 What can I do to make these adjustments hold? I've tightened them VERY tight by hand, but they still move. I've thought about very thin washers with rough surfaces, don't know where I'd find something like that.

 

Any thoughts would be appreciated.

Edited February 26, 20206 yr by Ron Altier
couldn't get pictures to download

Ron can you show a picture?

I had a lot of problems getting the pictures to download. Finally it accepted them.

How about make a washer from some self stick sand paper?  Or add some finish and throw some sand on before it dries.

How about using a compression washer?

Check Fastenal.com

 

Self stick sandpaper like Dan suggested works good. I cut them to size like a washer on both sides. Used 80 grit sandpaper.

I actually would go the other way around.  Put metal washers on the outside to keep the metal bits from sinking to deep to be tight.  With the metal washer on the outside the clamping pressure will surely hold tight.  If not then yes some self made sandpaper washer are the way to go but will be temporary.

 

Green felt paper. Green very thin felt with sticker paper on the back. Available at craft stores. Two pieces inside and two pieces outside with the green felt facing each other will give you the friction you need.