Machining Aluminum (Aggressive!)

I feel like it was not too long ago, I was here asking “how do I cut aluminum” and now I have my CNC flying! :joy:

Just wanted to share this quick video of my Onefinity machining some aluminum box tubing.
This was after some trial and error, but the end result is fantastic!
There are still a few things I need to tweak CAM wise (primarily the finish toolpath).

If I’m doing something horribly wrong, please let me know!

This is for my high school robotics team so speed is more important than a few thousandths of an inch, in an operation like this. Mainly just for weight-reduction and aesthetics.

That being said, measurements were off by 3-5 thousandths (inches) off…within our general manufacturing standards.

Onefinity WW
X-35 + Stiffy
Makita @ 20k
Onsrud Endmill
1/4in Upcut, single flute @ 0.004in
0.1in DOC

I know, I know…the first one plunged and didn’t ramp. :stuck_out_tongue_winking_eye:

Don’t mind my friend’s commentary lol…


I would definitely say I was taken back by the first cut - the second was a lot more “tolerable” – nice work!


Thanks for posting, very interesting to me since I like cutting metal!

I am curious if you have you tried running the router rpm slower?

Any plans to upgrade to a spindle on that machine?

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Before we kicked it up to 80ipm, we ran tests running the machine at 20-40ipm and the router as low as it can go (10k).

In the initial tests, we were also taking multiple depths, rather than one single pass.

We then tried single pass at 60ipm - worked great!
Next, we bumped up the feed to 80ipm, and therefore had to increase the RPM to balance out the chip load.

Sadly, I don’t think our machine will be getting any spindle upgrades anytime soon, but we’ll see. Right now, it’s just too much money (and time) for our team to invest in, especially since school is coming to an end (won’t have access to the shop until September).


Great work but look into protection for the rails. You will see some people using curtains or something. You have to make sure metal fragments stay out of the bearings.

Definitely! We are planning on disassembling the machine and setting up from scratch sometime soon, deep clean, new spoilboard system, polycarb rail guards, a better jig for the tubing and some minor improvements around the setup.

Thanks for the advice!

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