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View Full Version : Foot Rest Project and how I did nesting in Fusion 360



Washout
23-09-2016, 12:34 PM
Hi All,

Another one of those "quick" projects and maybe not the most glamorous, but it shows how I did some shape nesting in Fusion 360 i.e. at the "sketch" stage, as I don't think there's a true nesting function in the CAM section (if there is let me know):


https://www.youtube.com/watch?v=AI781ja7LHM

Boyan Silyavski
23-09-2016, 03:23 PM
NIce video! So- pattern for nesting. Not a bad idea. Unfortunately some expensive CAD CAM packages don't have good or any nesting.


So what are your typical speed feed and trochoidal step length and width for trochoidal toolpaths on wood or hardwood? I assume the width will be sth like 50% so chips could evacuate. But the step in % from tool?

Washout
24-09-2016, 11:57 AM
Hi Boyan

Feeds & Speeds should be on the video, but here they are for plywood and hardwood (same as I used on the alder Jaguar bodies):

Tool: 8mm Single Flute Carbide
Spindle Speed: 17,178rpm
Feed Rate: 2944.8 mm/min
Depth of Cut: 15mm - the feeds and speeds from GWizard were the same for 19mm, being the thickness of the plywood but the flute length was 16mm, so I had to use multiple passes.
Stepover: This is not constant through out each cutting move but has an optimum of 3.2mm or 40% of the cutter diameter. If you use 50% GWizard will throw a warning up. My understanding is that the cutting width should always be asymmetrical to the cutter diameter, or you can run into problems - I expect someone who's more experienced will know why, but I guess its so that the cutter if it is deflecting does so in a consistent direction and not on a "knife edge" where it can deflect one way or the other, like a ball bearing rolling down a knife edge perhaps.

I would say also that whilst my machine copes fine with plywood, its not as nice to cut as "normal" hardwoods as I think the glue/resin in the lamination is tougher on the cutters.

As for the nesting, its a bit of a hack the way I did it, but couldn't think of another and being a parametric modelling tool if I alter the original shape it should flow into the repeats and then into the solid bodies and the CAM, which is the main advantage I've found to Fusion 360 over other "free" CADCAM packages.