Pete.
I think i see now what you mean.
The plastic square part inside the handle is wearing away.
This must be because the handle isn't going back over the square part of the bolt properly.So probably need new ones.
I think you can buy better quality ones to suit.
Not been funny here Pete,but you do pull the handle out so you can change the position of it to suit your tightening requirements,and make sure that it as sprung back over the square part of the bolt,as this is the idea of the spring.
You should be able to pull the handle out to readjust the position of the handle for tightening and then it should spring back onto the square part of the bolt.
You have to adjust the spring bolt so you can turn the handle.
Either that or the handle is a poor fit to start with.
As you know Pete i have the Perform lathe and my handles do seem a little loose so i just make sure that it is fitted correctly when in use.
Same problem is with the big nut underneath the banjo,it does work loose so i just check it when i use it.
Hope this is clear :shock:
Paul.J.