Feed and speed for Aluminum no flood or air

Hi, could someone with experience download my fusion file and review tool paths and fix my feeds and speeds please, I need to make a bracket to hold my air/mist nozzle. My first aluminum piece so far, I would like to have it nice since it will be in clear view on the front of the Shapeoko from now on… I will study and use results for future templates. Will have to turn off models to see full tool paths, -.04 stock to leave is set.

Thank you!

Air/Misting bracket for HD 65 MM Spindle Mount

Mister

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@BubbyDog, I can’t look at your file now, but check out some of the toolpaths and conversation in this thread.

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Thank you Neil, very helpful!

I downloaded two of the fusion aluminum milling files and have studied the tool paths but none are a single flute and I am hesitant to use them, I think they are using air and lubricant also.

When I try to enter custom variables it constrains proportions between feet per second and spindle speed. I change one the other changes with it. I can not set my own parameters. Which has been confusing to me to try to adapt someone else’s f&s among other things. Most of the examples I have seen are in metric.
I was told the single flutes are best for aluminum? I got a 1/4 and 1/8 from C3D.
I was wondering should the Carbide 3d single flute tools be turned up to the speeds I am seeing recommended? Every C3D tool I get shows 10000 RPM, is that the limit? Every Amana tool shows 18000… Not sure what the difference is…

If you would not mind to download my F360 file and check it out when you have time, I do not mind to wait. I don’t want to trash any of my new tools being stupid.
Thank you for the help I really appreciate it!

Hi @BubbyDog,

Looks like you just fell in the rabbit hole down to the feeds and speeds Wonderland :slight_smile:

This is admittedly the hardest part in the CNC learning curve, and for me it was extremely confusing at first. I tried to make (some) sense of it all in this chapter of the ebook.

Since Fusion360 is a very generic CAD/CAM tool, the defaults feeds and speeds that come up in the toolpath window are also extremely generic, and steered towards very difference CNCs.

CC recommended settings will be a good starting point (especially in the latest releases, which introduced very sensible defaults), but I think it’s also worthwhile to spend a little time to get a basic understanding of how to adjust your feeds and speeds when your usecase does not quite match the available combinations of endmill/material available in Create or elsewhere.

I won’t even try to summarize this here, because…well if it took me 20 pages to scratch the surface of this topic in the ebook, I can hardly make any sense in a few sentences :slight_smile:

However here are a few pointers related to your questions:

That’s because surface speed is directly linked to spindle speed via the diameter of your endmill (that Fusion knows about). Surface speed is just the linear speed of the outside of the flute, so if you spin the tool faster, it increases. You don’t need to care about surface speed for now, what you should enter are spindle speed and cutting feedrate(s) (and then depth of cut etc in other tabs). Check the feeds and speeds chapter I linked above to see how feedrate, spindle speed, and cutter type are derived from each other.

This will get clearer after you read about that relation between RPMs, feedrate, and endmill flutes.

At least they are the easiest to use at first, and yes they rock for cutting aluminium. The main reason is that chip evacuation is easy due to that very wide (and single) flute, so the risk of jamming the cutter with chips is very low, hence the risk of melting chips in the flute is low. However, you need to adjust feeds and speeds versus e.g. the ones that would be used for a three-flute endmill.

No, that’s definitely not the limit, but this “10.000RPM” attractor in CC is (probably) to make the feeds and speed achievable both on a Nomad and a Shapeoko (the Nomad max speed is 10.000RPM, while the CCR min speed is not that far from 10.000). Again, after you read about feedrate vs RPM, you’ll be able to tweak that very quickly (basically, for a given endmill if you multiply the RPM by X, also multiply the feedrate by X). Generally speaking, for aluminium you will want to go for higher RPMs.

All of this being said, I’ll let @neilferreri comment on that Fusion360 file !

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Thank you Julien, this clears a lot up for me. Never saw the ebook before, will be reading it asap. Can I get a esigned copy? haaa… smh

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That made me lol :slight_smile:
What you can do is provide feedback/comments/ideas about what’s in the book and what should be in there, I’m more or less continously updating/improving it as a background thing, for the next release.

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