Machining thin-walled aluminum tube

Hi everyone,

We have some extruded 6061-T6 aluminum tube (3.25" OD, 0.125" wall, 30" length) that we're trying to finish to cosmetic standards. The tubes came from the supplier in normal rough metal shape and after tumbling, bead blasting, and anodizing, there are obvious scratches and nicks that are too deep to remove via finishing methods.

I'm wondering if it's possible to mount the tube on a lathe between centers (self centering chuck on one side, super large live center on the other side) and peel off 0.010" or so from the surface to expose a fresh surface that only contains light machining marks. Although the tube is extruded, some casual measurements indicates that concentricity and distortion in the tube shouldn't be a major issue.

My concern is with flex in the aluminum and getting a chatter free cut throughout the length of the tube. Does anyone have any tips or feedback on how I might approach this project? Thanks!

???cosmetic standards??=== ?? matte finish? mirror finish???
??any thing definable??


Spin roll it between 2 sets of double rolls, polish with 3M fibertex pads using angle grinder,
hides/removes the NORMAL handling dings, etc. that comes with mill stock.

You should get tube in better condition to start with.

If you have extruded tube that doesn't clean up after tumbling AND bead blasting (that must be a large tumbler), they must have done something really heinous to it.

ideally, It should not have been accepted in this condition. not normal! I hope you aren't stuck with much of this.

If you have to clean some of it up, I'd try the abrasive route before the machining. Scotchbrite? angle grinder.

(.125, not that thin..)

It's going to be tough... your going to find OD is not very round nor concentric to the ID. Check with some of the plating houses and see if they have any methods the etch then chem polish them. Otherwise you may have to replace the material...

scadvice said:

It's going to be tough... your going to find OD is not very round nor concentric to the ID. Check with some of the plating houses and see if they have any methods the etch then chem polish them.

Click to expand...

how is etch and chem polish going to get out scratches that tumbling AND bead blasting didn't?

agree on ID-OD disparity potential for extruded, thus my first recommendation..

cyanidekid said:

how is etch and chem polish going to get out scratches that tumbling AND bead blasting didn't?

agree on ID-OD disparity potential for extruded, thus my first recommendation..

Click to expand...

Damn if I know... it was just a thought that maybe would lead to a solution. I've see more than a few thousands etched taken off.