In article m, Ken
Sterling wrote:

Gang,
Got a piece of glass tubing (similar to Pyrex) which is .490 ID,
.625OD and I need to cut a piece about 11/16 long. File won't touch
it, glass cutter won't do it, have been trying to score the outside
with a thin "cutoff wheel", which scores it, but the stuff won't "snap
off" as expected... just shatters, even past the score mark. Am I
going to have to cut completely through with the cutoff wheel to do
this?
Ken.



Sounds like the tubing is old.
The older glass gets the harder it is to cut clean.

Try a small diamond cutoff wheel in a dremel tool.
Score it all the way around.