A friend who is a good overall fabricator and often has good ideas came up with this one when I told him how much I found my my 1 inch pipe was deflecting when I made the (had to be done) mistake of putting on a dial indicator.
He suggested putting a hardwood dowel inside the pipe and epoxying it, then went further and suggested expanding foam.
I see no problem with the idea it sure is cheap enough, and have even bought the dowels and foam.
There is .030 clearance around the dowel (with my particular dowel and pipe). I think it is crazy enough it just might work, and might even reduce some resonance in the pipe (or increase it, as this is just arse talk till it is tried)
As I said, I have the stuff, but have not tried it yet. Any input here guys?
Check out the picture if you miss what I am rambling about.
Northboy