Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Soft tubing is Really Really Hard to cut square. Best I can do freehand is with a straight edged razor blade while hosted on an I.D. sized piece of rigid tubing, dowel or rod acting as a mandrel, but even then, it is a challenge.

If I really need it as perfectly square as possible, I do the above with the mandrel piece chucked up in my lathe, with the razor blade held ridged against the side of the tool post and turn the chuck by hand. Sometimes, it still takes several tries, even when set-up like this!