I'm in need of a small amount of telescopic square or rectangular steel
tubing (24" long outer piece and 24" long inner piece). The dimensional size
of the outer tubing is not critical, but I'm looking for something roughly
2" x 2" square. The inner piece must be able to fit entirely within the
outer piece, must slide freely, yet must not be a sloppy fit.

If I were to buy A500 series structural square steel tube:

- 2" x 2" x 11 GA (0.120" wall) x 24" long (for the outer piece)
- 1.75" x 1.75" x 24" long (for the inner piece)

would that work? Or will I have problems with interference from the welding
seam and surface finish inside the outer tubing?

I know there are manufacturers of hitch receiver tubing and other industrial
telescopic tubing, but I don't know of any supplier of small (and reasonably
priced) quantities of the stuff.

Thanks,
Michael