5 Axis Milling?

[Anonymous]

Hello all,

I am hoping to get some direction here (feedback, URLs, literature, etc). I'm new to milling but quite proficient in 3D printing (having built numerous printers). 

I have a need for five axis milling for cylindrical objects having particular embedded rotary patterns.  Yet, know nothing about milling (as of yet).

I have designed this 5 axis machine which I know I can construct after I build my 3 axis machine to facilitate fabrication.

The fabrication is the easy part.  Where I am stuck is (at this time) knowing nothing about all of the driving mechanisms (from software to stepper drivers to control boards).

My understanding is that Fusion 360 can handle 5 axis milling (I also saw something by the name of "Power Mill" (I think) by Autocad too).

But, how does it all work?  Is it like 3D printing?  Does Fusion 360 "slice" the object and then create tool path movements?  Is it a g-code kind of thing?  What types of control boards can I use... Arduino?  Do I need special stepper drivers?  

Where can I learn what I need to know to complete this build-out and actually make it work?  I'm comfortable with configuration files and all of that, (actually have an IT background) but I don't know where to begin.

Thank you so very much and all the best,

Trip

[TrippyLighting]

Depending on what material you want to mill, stepper motors are not the best choice. On a 3D printer there is really no back pressure/force to speak of on the print head.

When milling, however there is significant reaction force on the milling tool as you move it forward into the material. If the force is too high a stepper motor might not step and you basically loose your position  For softer materials this might not be a concern, but you'll likely want to use use more powerful stepper motors and drivers as compared to a 3D printer.

[davebYYPCU]

Fusion's CAM section will give you proper Gcode, not sliced Stl style gcode.

I used CNCZone.com as a general forum for the machine and components, electronics and programming.

I agree with Trippy, derived 3D printer components won't do it.

[etfrench]

An Arduino is not capable of running a 5 axis CNC machine.  LinuxCNC would be my first choice as it can do 5 axis.  I'm using it on a 3 axis CNC router. Stepper motors work fine as long as they are sized appropriately.

You'll need stepper drivers for all 5 axes, more if you're using multiple steppers on a single axis, and a 5 axis breakout board.  You'll also need a low end computer with a parallel port to run LinuxCNC.  There are newer solutions that use ethernet instead of the parallel port.  Note:  There are some stepper drivers that are notoriously bad, so do your research before buying.

I'd recommend posting your design on CNCZone.  (The hard part is deciding which forum to post on ) I'll predict they will tell you the design is not rigid enough, but they will also offer a lot of good advice on how to fix it.

You'll be creating the toolpaths in the Fusion 360 CAM module.  See the CAM section on the Learning pages.

[Anonymous]

Thank you Trippy!

I have also been looking at Clear Path servos.  They are a bit more expensive but perhaps worth the investment.  I am however looking at milling aluminum as the hardest materials for now.

All the best!

Trip

[Anonymous]

Thank Dave!

I'm gonna be checking out both Fusion's CAM tools and CNCZone.  I was hoping NEMA 23 high torque motors could handle aluminum, but maybe servos would be better.  Looking at these... 

All the best,

Trip

[Anonymous]

Thank you ET!

All really good information.  I guess I'm gonna have to dust off my unix skills and build-out an new Linux box.

Thank you for the clarification on stepper size.  I'm hoping NEMA 23 high torque motors will do (for aluminum) but if not, I have my eye on Clear Path servos.

Oh, I almost forgot, can you please tell me what the breakout board would attach to?  Just a breadboard? Or a specific controller board?  If so, what do you recommend? When I hear the words "breakout board" I usually think of a "shield", "daughter board" or something similar (that plugs into another board). Perhaps in this case it's simply stand-alone.

I will most certainly join CNCZone and check out Fusion's CAM pages.

All the best and thanks again!

Trip

[etfrench]

The breakout board is just a convenient way to connect the stepper drivers and limit switches to pins on the parallel port (or ethernet).  It's just mounted in an enclosure located in a convenient spot.

My CNC router is using 425 oz-in steppers, but 280 oz-in steppers would have been strong enough. The supplier didn't have any smaller dual shaft steppers when I ordered, so ended up with the larger steppers. The rigidness of the frame will be more of a determining factor on whether or not you can mill aluminum or steel. 

I'd also recommend designing an enclosure for the machine as milling aluminum can throw the swarf a very long way from the machine.  Consider whether you want to use coolant as well.  I use compressed air to keep the bit cool and remove the aluminum chips.  I use a dust collector vacuum for wood machining.

Here's what happens when the bit gets a bit dull and there isn't enough cooling:

[Anonymous]

Eeeeee, that's not pretty!