I am looking for the name of a ribbed washer. If you bolt two wood pieces together at the end to form an elbow lap joint........the joint will slip.  I want to have the ability to adjust the joint angle, but I want it to be secure after it is adjusted. The drawing is crude but I think you get the idea. Two of these with the ribbed side facing each other will hold. I've seen these things before and probably can buy them, but I don't know what they are called..................... I'll take other ideas too.

 

Thanks

https://itafasteners.com/products-washers-rib-washer.php

"Wedge lock washer" is what you are looking for.  Ebay would be your best bet to get them in small quantities.

 

Glue some 220 sand paper to the arms would do the same thing.

 

Edited July 9, 20215 yr by HandyDan

9 hours ago, lew said:

https://itafasteners.com/products-washers-rib-washer.php

Thank you, I had no idea

I did the sandpaper route that Dan suggested for a dust collection port and it worked great at almost no cost. I think I used 80 but any grit will probably work.

I finally remembered where those washers are used..............bicycle axles......to keep the bolts tight.