Used higher pressure in the blast cabinet to to the interior of the tube, (there was some rust).
Lowered the pressure to around 40 psi to clean the exterior.

Took the tube to a local hot dip galvanizing facility and they did it while I waited. Came out way to shiny, but it got the interior coated, which was the critical part.

Filled a bucket with white vinegar and soaked the tube overnight. That dulled it nicely. Then used 0000 steel wool to polish certain areas back out.

End result was very satisfactory. I'm on the road so no pix. Will try to get you something by week's end.

Ken