- Joined
- Dec 7, 2015
- Messages
- 519
Good point; I didn't consider that. It also creates way different chips, leaves a near mirror finish, and doesn't "scream" like the corncob one from MariTool.
-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Aluminum Roughing End Mill: Recommendations?
- Thread starter wildo
- Start date
Good point; I didn't consider that. It also creates way different chips, leaves a near mirror finish, and doesn't "scream" like the corncob one from MariTool.
- Joined
- Jan 11, 2018
- Messages
- 308
I noticed that the Mari end mill was howling in the video too.
Whining End Mill
I have this new 1" Niagara rougher end mill I acquired. Of course I had to get an end mill holder for it. Mistake as it is unusable even at the lightest cut. Made a short vid on a piece of scrap.
www.hobby-machinist.com
- Joined
- Dec 20, 2012
- Messages
- 9,422
Looks good, Willy. I've been meaning to try that variable helix thing for some time now. Still not sure how much difference the coating makes. My uncoated cobalt roughers seem to last forever and do not gall in aluminum so ...
I agree with the length or stickout thing. I'm sure the other guys have a better way to do it but I try to order end mills with a flute length about double the diameter or less. For a 3/8" end mill, I want 3/4" flute length. This lets me maximize my ADOC and RDOC while minimizing deflection. Getting the end of the flutes up close to the collet and using an ER collet also reduces deflection and vibration, which is what is causing that howling you guys are talking about.
Roughers are awesome but remember to size them so you have about 0.010" left to finish. As nice as the finish is with that new rougher, it will still leave marks that will need cleaning up on a presentation face.
I agree with the length or stickout thing. I'm sure the other guys have a better way to do it but I try to order end mills with a flute length about double the diameter or less. For a 3/8" end mill, I want 3/4" flute length. This lets me maximize my ADOC and RDOC while minimizing deflection. Getting the end of the flutes up close to the collet and using an ER collet also reduces deflection and vibration, which is what is causing that howling you guys are talking about.
Roughers are awesome but remember to size them so you have about 0.010" left to finish. As nice as the finish is with that new rougher, it will still leave marks that will need cleaning up on a presentation face.
- Joined
- Jan 11, 2018
- Messages
- 308
That looks good. Now start feeding it as hard as your motor and mill can handle. That end mill can handle .01" IPT.
- Joined
- Nov 27, 2012
- Messages
- 7,912
So.... how do my roughing chips look like that I made yesterday? Don't ask me all the numbers cause I dunno really. Feel, sight, & what my mill yells at me is what I go by these days most of of the time. 
