Shrink fit frame-valve collar
Well, my collar in the back of the frame has always been a tad loose and the grubscrew holding dimple has become elongated
So….
Im planning on making a stainless steel threaded bushing with much better tolerances and will be fully threaded so that the bottle is held by much more threads than the normal 1.5 turns of the original.
One thing though, Ideally, I would want to shrink fit the bushing in place, but I don’t want to start waving the blowtorch around the frame so I was wondering if sticking the bushing in the freezer would shrink it enough to be a slight press fit in the frame, but at normal temperatures it would return to size and be a tight fit, and then still use the grubscrew for added security.
If this is not possible, what are the tolerances for a goor press fit, I don’t fancy using a large press on the frame and would go for the “Lump of wood and a good hammer” method?
Thanks
Dave
All Replies
- You must be logged in to reply to this topic.

I once drilled several very precisely located holes in a piece… only problem was they were all precisely off by .1″ because I forgot to subtract the edge finder radius….