On Wednesday, June 6, 2018 at 4:53:22 PM UTC+1, Andrew Mawson wrote:
"misterroy" wrote in message
...

Hi, I am after a die holder, one that will stand up to use by school pupils
who have a tendancy to over tighten the grub screws stripping the threads,
and making the holder useless. We have re-tapped the holes, but they get
stripped again.
Only the holder, any recommendations?


Helicoil the tapped holes - the material helicoils are made from is
extremely tough - alternatively re-introduce the concept of discipline into
the school - tell them not to then enforce the instruction.

Andrew

I like the sacrificial screw and the helicoil suggestion.
The enforcing the instruction does not work. They lack the experience to know how much force is too much. I was once busy keeping things safe at the forge and I could see a pupil working with a hacksaw. It was 8mm annealed silver steel he was cutting. I saw him hard at it between the pupils I was supervising at the forge. After about 25 minutes of him sawing, there was no-one to supervise at the forge, so I went to see him. He had made a 2mm deep cut, in 25 minutes of work. I had a go. I added very little to the cut, but I knew something was wrong. The only teeth on the hacksaw were in the last inch at the ends. In the middle there was not even a sign of teeth it was rubbed smooth.