Problem Bought pulley stock, but the machinists can't guarantee the concentricity of the bore

Hi guys,

I've bought a pulley stock 200mm long, it's made out of aluminum 6061 T6.

I need to cut 14mm wide pulleys with a bore of 10mm, the problem is that two different machinists(manual lathes) told me they can't do it because they wouldn't be able to get the bore concentric with the pulley's profile(teeth) the most honest of the two told me it'd be 0.1mm out of concentricity at best.

I saw another guy who had a CNC lathe and several manual lathes, he acted like no problem he wanted to do it on a manual lathe, but when I told him about the concentricity issue saying I want it be done on the CNC lathe, we zero the stock with a micrometer we cut one pulley and we check it if it's fine then, we cut the rest, it was like he was caught and he tried to escape by saying the CNC lathe operator ain't here if you want to wait for him...I never saw him.


Can anyone explain how this is usually done by a pro ? (making pulleys out of pulley stock)

What kind of machine/tooling should be used to do it properly ?

Any tricks are welcome, thanks !
cnc2.