I gave it a fair shake trying to look this up on my own, but no luck. I even tried some quick heat treatment following no particular directions to see what would happen.
I'm cutting off a huge number of 1.75" long parts from 6ft rods of 3/8" dia 6061 (temper unknown) using a carbide cutoff tool on my lathe. Not only does the cutoff tool cut (this metal) poorly (it's a good bit), but pretty much any other lathe tool I use to machine (facing, turning, etc) this cr@p leaves a horrible finish and poor quality parts. It's essentially too gummy and squishes instead of cuts. All I really need to go is get a clean cut off, and a decent looking face (after facing operation). Right now it just scrubs and squishes and looks terrible.
I already bought a large quantity of the 3/8" dia rods for using in manufacture of parts, so just "trying another source" won't work. I have to use what I have and I have to find the best way to cut it. The process for making these parts is pretty much set in stone so I don't have much option. It has to be done on the CNC lathe. Previous batches of the same rod from the same company did not have this issue so I imagine it's either a problem with the temper of the aluminum, or it is a "bad batch" of metal.
I do not know what the temper is (T6, O, T651, etc), just that it's 6061 aluminum. I've heard of other's doing some heat treatment to improve it's machinability but can not find any more info.
On my own, just to try it, I attempted to heat up a section of rod with a handheld torch for several minutes, then plunged it into a troph of water to quench. Seemed to make a slight improvement in machinability, so I'm assuming that attempting to harden the material is the correct course of action rather than trying to further anneal it.
I did find instructions that said to heat to 900 degrees F for two hours then quench in water. Not sure I can stand there with a torch for 2 hours :-), so just wondering if anyone else has an experience with "real world" heat treatment as a fix for gummy aluminum. Tips, tricks, something easier than standing there for 2 hours with a torch, all help appreciated! Especially feedback on positive or negative experiences with heat treating in similar circumstances.