(03-08-2017, 07:20 AM)Mayhem Wrote: [ -> ]OK - this is going to sound like a smart arse response but it isn't - have you checked that the spindle isn't running in reverse? Yes - I accidently did this once when I first got my mill, as the switch is the dead opposite to my lathe 
Not at all Mayhem, I already thought of that but no, it's running forward.
(03-08-2017, 07:20 AM)Mayhem Wrote: [ -> ]have you checked that the spindle isn't running in reverse?
Been there, done that with my old mill. I wondered why the drill bit wasn't cutting worth crap. I had to switch two wires on the VFD to fix it.
Ed
Accidentally did that with a 24" carbide insert face mill on a Lucas boring mill. Of course it was right after I had indexed all the inserts so I'd have a new cutting edge.
Some long end mills are just prone to chatter. If you don't have another one to use, what may help is to step your way down, milling the pocket to finish size at each step. That will reduce the amount of cutter in contact with the work when it's at full depth.
Tom
I tried that, started off at about 1/4" and then worked down to almost 1/8" and it still squealed. Maybe just a cheap bit it came with the 80% jig.
(03-09-2017, 11:59 PM)Thumb Wrote: [ -> ]I tried that, started off at about 1/4" and then worked down to almost 1/8" and it still squealed. Maybe just a cheap bit it came with the 80% jig.
Is it a router bit or an end mill? Those jigs usually us a router to mill out the magazine well. But then I don't know what jig you have so I could be all wrong.
Ed
The jig and bits I bought from Ares Armor(now AWC). The ones in question are the 3/8" 4-flute center cut bits which I believe are end mills.
Those are definitely end mills.
Ed
Usually, in aluminum, it's recommended to use a 2-flute end mill.
(03-11-2017, 11:44 PM)Roadracer_Al Wrote: [ -> ]Usually, in aluminum, it's recommended to use a 2-flute end mill.
I'm going to get 2 & 3 flute and see what happens.