My first CAM Attempt

Lots of firsts in this post… First time using fusion 360, first using any CAM, first post on this forum.

Basically, I ordered a shapeoko yesterday and figured I should spend the next few days learning CAM so I can do something with it when it shows up.

So after watching endless YouTube’s and other tutorials (some by Winston Moy) I crafted the linked fusion model…

Requesting feedback on tool settings, rest machining, step overs, operation time, feeds/speeds, etc… Can’t imagine that I did everything right, but did I miss anything glaringly obvious? What can be improved? and finally….If I try and run this program once my Shapeoko shows up would anything blow up spectacularly in my face?

Thanks in advance and let me know if this type of question format is acceptable long as I’m providing the design rather than asking for you to do it.


Nothing like jumping in with both feet! They are relatively complex tools, and you’ve made a model that’s particularly hard to machine.

All of the things you ask about above depend a lot on the tool. From the model you’ve made, it’s actually very hard to machine and get a result you’ll be happy with with a single tool, which means multiple tools (at a minimum). Remember, the end of a square endmill is…um…square. Without very small stepovers (that will also wear out that kind of tool on this kind of cut pretty quickly) you’ll get large steps in the angled faces. They’re great for a “roughing” pass to get most of the material out of the way. Then follow that up with a ball endmill, and use that for the angled faces. You’ll still get some stepping, but less, and it will be more “wavy” than stair-stepped. You’ll still need a touch of finish sanding when you’re done. I’d start with a .25" square tool to rough out the majority of the waste stock, then follow up with a ball end mill, and maybe follow that up with a tapered andmill with a smaller stepover. That would be a 3d “pocket” path, with maybe a .125 stepdown, and .125 stepiover. Follow that with a round endmill, ⅛", and a .065 stepover (and stepdown), and see how it looks. then might try a smaller stepover and see if the result looks ok to you - expect some wanyness in the surfaces, but see how it looks to you. Follow all that up with a ⅛ outside contour. You’ll want to export all those paths as single files, and after each one, change the tool to prepare for the next, run that, and move along like that. Using carbide motion as a sender is a good place to start. Use the feed/speed from the carbide chart (find it in the documentation on the website) - it’ll be conservative, but it’s a fine place to start.

It’s all a learning experience. You’ll pretty rapidly find the adjustments that make sense, what you can speed up, and what you can’t.

There are some things that are really easy on an additive machine (like a 3d printer) that are more difficult on a subtractive machine (like a 3 axis mill) - and they both get different results… sometimes something that’s trivial with an additive machine is just plain impossible to do in one piece on a 3 axis mill (like a hollow sphere!). Faceted surfaces are one of those things. It’s not that you can’t o faceted surfaces, it just requires more thinking things through and knowing what the machine will accomplish on it’s own. That all comes with experience. 2.5d stuff is fairly easy on a 3 axis mill, it might be a better place to start, I’d hate to see you get really frustrated trying to get good results on this particular model as your first foray.

Cutrocket has a number of projects that you might want to try first, just to become familiar with all the processes. Maybe something like this: , or maybe this: . I don’t want to discourage you from trying some cool projects, but you might be taking on something a little more that you think you are.

Again, don’t let me discourage you!


Awesome, thanks for the thoughtful response, I’ve always been a reach has far exceeded my grasp kinda guy… just rarely does it have the ability to fling high speed shrapnel at me.

So to summarize instead of:

  1. 1/4" flat bottom adaptive path
  2. 1/8" flat bottom parallel path
  3. 1/32" ball nose parallel path

You’re recommending:

  1. 1/4" flat bottom adaptive path
  2. 1/4" ball nose parallel path
  3. 1/8" tappered ball nose pocket clearing path
  4. 1/8" ball nose parallel path
  5. 1/8" ball nose outside corner path

I’m going to have alot of 1.5" thick laminated plywood scraps from another project; so materials wise I don’t care too much. It’s more the 2hr machining time I had programed for my 1/32" ball nose that could potentially discourage me. Lots of “shut up and color” time there just to see if I’m going to be pleased or not. But I hear you and thx for the links; last thing I wanna do is blame the machining on the plywood and stick some 2.25" thick walnut stock in there just to see if it would make a difference and end up disappointed.

Probably be a week or two before I get up and running; but I’ll post results here on various work pieces and let you know how it goes.



Cool design you made, and its sporty of you to go with Fusion 360 from the start, I did the same and it was a steep, but fun learning curve which i dont regret from choosing. I used trial and error along with youtube to get to the point where i am now -comfortable with all operations, and can even spit out some usefull parts in aluminium.

I dont know anything about your machining experience, but I started from scratch, and Fusion 360 was the least of my problems. In general the problems were never in my designs or g-code, always something at the machine.
In the beginning I used “Boring” designs like the one posted below, to learn correct cutting parameters for the material i worked in. The dimensions and finish of a part like this will tell you the state of your machine when it comes to mechanical rigidity, tramming of router and accuracy of steps/mm settings in grbl.

Dont entirely trust the CAM parameters here, as this has been used for trial and error. Its just meant as an example of a good practice part in Fusion CAD & CAM and the most important in my opinion, machine tuning, setup & understanding along with workholding.

The part you have designed is really cool, good job with both design and CAM.
Im sure this will come out really nice once you get the hang of the machine!

I wish I could give you more feedback on your CAM question with regards to feeds and speeds, but I dont know what material you are planning to work on. As in general the parameters will work fine as a base that you can adjust to your limits once tested. Not too aggressive for a properly mechanically assembled machine IMO.

I can only speak for myself here, and I think its a great way of presenting a question.


Also, surprisingly Julien missed this, but those holes, especially the more highly angled one, will be impossible to mill completely without somehow angling the part so the endmill can come in perpendicular to the hole. Endmills can’t go around corners so you’ll end up with an ovular hole and not a circular one.

Does that make sense?


Yes it does! I was actually wondering about that myself, but can’t really interpret the blue lines on the g-code very well yet…

So if i wanted to bore out any type hole it would have to have the hole be co-planer with the stock top&bottom, correct?

Correct. Since the z-axis is in a fixed vertical position, it can only mill perpendicular to it’s direction. You would have to orient the part so the stock is perpendicular to the z-axis in order to mill that hole. This isn’t hard with a vise and angle blocks if you really want that hole angled.


to make this part you would need a 5 axis machine, or use some sort of fixture

check this out

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