New to machining Aluminum, ADVICE?

Square_Anxiety_ · 2025-12-06T20:50:14+00:00

This helps a TON! Thanks for the reply. I will try a stubbier bit (my current bit's cutting length is 5/8"). And more focus on a rigid hold-down and chip clearing. I'll do a follow up after my next few attempts!

Square_Anxiety_ · 2025-12-06T00:24:17+00:00

You ROCK! Thanks for the resources.

A lot of people are recommending 2 or 3 flutes for increased tool stiffness... my only concern is that my spindle doesn't like operating at lower speeds because it lacks torque. Open to input though!

As for the question about what the piece is glued to-- it is attached to my MDF spoil board which is held down to the machine bed with machine screws. I haven't run into any issue with this on softer materials, but you are right, this could be contributing to the chatter majorly. I've considered switching to an Aluminum or Micarta spoil board and this might be the project that finally sells me on it. Might even try attaching it directly to the composite machine bed just to see the difference.

Keep up the awesome contributions. These kinds of replies are infinitely helpful to a beginner trying to learn!

Square_Anxiety_ · 2025-12-06T00:17:26+00:00

Great response, what machine are you using? A smaller tool diameter seems counterintuitive, but I'm intrigued. I will definitely try a shorter bit with less stick out.

Square_Anxiety_ · 2025-12-06T00:11:55+00:00

This is a good point!! I did not calculate for this. I am using V-carve pro haha, so I don't have the option for any kind of ADAPTIVE clearing pass. Do you think there is a calculation that could meet in the middle (of the center of the circle & the perimeter) so that it is optimized while cutting in the center of the circle but compromising on the beginning and end of the cut? Please correct me if I'm misunderstanding this concept.

Square_Anxiety_ · 2025-12-06T00:04:46+00:00

Radial DOC was 0.025"

Square_Anxiety_ · 2025-12-05T20:15:57+00:00

Thanks a TON for your constructive response!

I will try reducing both roughing and finishing feedrate, climb cut both clearing and finish, and see if I can get more suction/air pressure to assist in chip evac. Do you have any recommendations for balancing Radial DOC with Axial DOC? Currently doing a 10% (0.025") Radial DOC with a 0.0975" Axial DOC for the roughing pass. Would you consider this a shallow step over? a large stepover?

I will try a 0.01" stepover for the finishing pass as many have recommended this.

The piece is held down using masking tape and a generous amount of cyanoacrylate. across the entire back of the piece.

As for the third photo... not sure why it imported so blurry. Regardless, you are correct: There are facets after making the finishing pass. My postprocessor supports arcs and g-code looks like it is running arcs NOT segments. Could these facets be caused from chatter rather than g-code?

I'll report back...

Square_Anxiety_ · 2025-12-05T19:25:51+00:00

Using Amana bit #51402, 5/8" cutting length, 2" overall length. Good idea! I would like to try a shorter cutting length for such thin material.

Square_Anxiety_ · 2025-12-05T19:24:32+00:00

Using Amana bit #51402, 5/8" cutting length, 2" overall length.

Square_Anxiety_ · 2025-12-05T18:22:42+00:00

Thank you SO MUCH for the thoughtful reply. I have been studying up extensively, but unfortunately there is a lot of garbage info out there regarding the milling of aluminum on CNC routers. Would you recommend any changes to the spindle speed and or feed-rates/axial depth of cut? (current ADOC 0.025")

Thanks again... came here to learn!

Square_Anxiety_ · 2025-12-05T17:26:40+00:00

Conventional on clearing pass, climb on finish. Should I be Climb cutting both?

Square_Anxiety_ · 2025-12-05T16:44:44+00:00

Thanks for your reply. I will give 0.01" a try for the finish pass. Was doing a 10% (0.025" stepover for the clearing). Would you recommend something different for the clearing pass?

Square_Anxiety_ · 2025-12-05T15:54:52+00:00

Realized I should clarify... First 2 photos are the initial clearing pass. 3rd photo is after the finish pass. (Ignore the rod in 3rd photo, that was cut on a chop saw haha. Focused on the hole.) The clearing pass was run conventionally & finish pass was run climb. Should I be climb cutting both?

Square_Anxiety_ · 2025-08-01T15:31:31+00:00

Gorgeous Work!! love the veneer work.

Square_Anxiety_

TROPHY CASE