u/Cubivs_Official

Finally got a brass cut that I’m actually really happy with.

This is probably the smoothest metal surface I’ve managed to get so far.

But I’m wondering — what are your tricks for getting really smooth, clean flat surfaces when machining metals? I’d love to hear what settings or toolpath strategies have worked well for you.

Here’s the setup I used:

Material: Brass
Machine: Cubifab 3-Axis Desktop CNC
Spindle: 8,200 RPM
Tool: 4 mm flat end mill for aluminum
Feed rate: F1200 mm/min
Depth of cut: 0.2 mm
Stepover: 70% of tool diameter
Toolpath: Pocket Milling

Hey everyone, sharing a quick look at our desktop CNC machining a 6061 aluminum part.

This is still a work in progress — we’re waiting for our vise and matching aluminum jaws to arrive, then we’ll finish the remaining operations and clean it up.

Would love to hear your thoughts on the machining process, especially if you have any suggestions for improving our settings or surface finish.

Here are the current parameters:
Material: 6061 Aluminum
Spindle Speed: 6800 RPM (roughing) / 8000 RPM (finishing)
Tool: 6mm flat end mill for aluminum
Feed Rate: 1500 mm/min (roughing) / 450 mm/min (finishing)
Depth of Cut: 0.4mm (roughing) / 0.08mm (finishing)
Step Over: 75%
Toolpath: Follow contour of the part

Hi everyone, I finally finished my first aluminum part on this machine!
Really appreciate all the advice and suggestions from this community on my previous questions. This time I managed to finish it without any crashes or broken tools, and I’m honestly pretty happy with how it turned out.
I’d love to see some of your favorite aluminum projects in the comments! Also, if you have any fun ideas for what I should try making next, I’d love to hear them.
Thanks again for all the help!

Machine settings:
Material: Aluminum block
Machine: 5-axis CNC prototype
Spindle speed: 6400 RPM (roughing) / 15000 RPM (finishing)
Tools: M4 flat end mill, R0.5 ball end mill (smaller cutters are on the way!)
Feed rate: 2000 mm/min (roughing) / 1000 mm/min (finishing)
Depth of cut: 0.2 mm
Stepover: 0.2 mm

Hey guys, we made this little moon with our 5-axis prototype using POM.

We messed up the tool setting during the first roughing pass, so there are some imperfections on the surface. Given this was also our last piece of POM, we decided to just keep going and see how it turns out.

Overall we’re pretty happy with the result, but there are still some fine lines on the surface. We limited the spindle speed on this prototype, so we think a higher RPM might help get a cleaner finish next time.

Would love to hear your thoughts:
Is there anything we could improve with the tool setup?
Would a different cutter or material work better for this kind of detailed 3D carving?

Material: POM
Spindle power: 2100W
RPM: 10,000
Tools: M4 flat end mill, R2 / R1 / R0.5 ball nose cutters
Feed rate: 2000 mm/min
Depth of cut: 0.2 mm
Stepover: 0.2 mm
Toolpaths: Parallel finishing + contour cutting

Thanks for any advice! Curious to see how we can make the next one better.

Been working on a little fan project — a CNC’d version of Haaland reimagined as Vermeer‘s Girl with a Pearl Earring. Thought it’d be a fun one to share with this community. 😉

We‘ve uploaded the STP, STL, and NC files to Google Drive — link below. Feel free to grab them and give it a go!

https://drive.google.com/drive/folders/1rVuusOL53ArFGQ3jL12krEPgxUhp-EnD

After a few false starts, I finally got a run that felt like real progress – almost to the finish line. Here’s the setup that got me there:

• Material: POM (Delrin)
• Spindle: 10,000 RPM
• Feed rate: 2500 mm/min
• Tools: M4M1 flat endmill for roughing, R2R11 ballnose for finishing
• DOC: 0.3 mm per pass

However, the ballnose snapped clean off during the final finishing contour. Why did it break at the very last moment? And what can I do to avoid this?

Looks like POM just isn't gonna work for this project. （Sorry, Ronaldo – we love you, that was a beautiful goal, but we're gonna have to make a good one out of something else.）

Hi everyone, I'm getting visible tool marks/scratches around the edges and corners of my workpiece, and I'm trying to understand what might be causing it.

I'd really appreciate any advice on what parameters or process steps I should check first.
Current setup:
Material:Black POM
Spindle speed:5000 RPM
Tools: M4 flat end mill for roughing, RO.5 ball end mill for finishing
Feed rate: Not fixed / varies depending on the toolpath
Depth of cut: Around 1-1.5 mm
Cut direction: Climb cutting
Toolpath strategy: Roughing + finishing, with around 1-2 mm stock left for finishing
Chip evacuation: Not sure yet - possible chip buildup or recutting still needs to be checked