i have a r schon from the early 1980's.
the micarta ferrule, cracked, so we replaced it with a
g-10 light green rolled material--ferrule, I did it as a 5/16x18 inside threads, the outside of the shaft was a small diameter, the shaft had been worn or taken down to just over 11mm. So the wall thickness was minimal, but this was perfect for a material like--g10, so from there we put on a vintage champion tip and after all this,
the customer, LOVED the outcome of the installation, by the way, the tennon was threaded and capped with about a 1/6" cap. With the fiber backed tip it played very nice and the feedback was good and the customer was very happy and no mechanical failure have occurred since the repair was done, this was done in 2009, so it has been installed for over seven years without a wall cracking and no issues.
Hope this helps with info and feedback,
respectfully
mike 'acedonkeyace' kennedy
The CueMan--Kennedys Billiard ProShop and Repairs
Largo, Florida 33771
OPhone# 727-277-9853
Take Care:grin: