Mickeyspinn
rBotM Winner
		Hmmm I'm down a rabbit hole of reading research papers and such  ...I really should be doing other things 
...nevermind a bit of learning isn't so bad! it seems that the process of extrusion and what it does to the tubes surface on a granular level is gonna be a hard thing to etch to the extent I'd like....the difference between 6k and 7k  grade  composition on a metallurgic level  doesnt help too!  Effectively in laymans terms the tube surface has a directional grain caused by the extrusion process so short of removing this  "skin" it won't give a result 
 and it's quite possibly not a good idea too I reckon for Integrity 
 shame quite taken on the galvanised gas pipe look!
Oh well back to ghetto paint I think
				
			Oh well back to ghetto paint I think