Interesting thread with some valid points and opiions.
I need to gob off again init?
My appalling mis-use of an apostrophe, was not my use at all, simply repeated, read the thread.
It don't matter what material you use you will only ever achieve precision by making bushes to fit each pen as a one off.
There is so much fluctuation between the tubes from one to another of the same batch, it don't matter how precise the bushes are if the tube don't fit on em init?
You would get more precision by not using bushes and turning directly in the tube.
