Hello all. I have been working with my Nomad and using Pine as test wood to get things set up correctly. I need to remove some good sized portions (like 5" x 5" x 1/2") and in general I am happy with the results since I am going to sand it anyway. Here are the settings I have been using with Fusion 360
Bit 1/4" 2 Flute Bit
Speed 8000
Feed Rate 40 in/min
Feed per tooth .0025 in
Maximum Roughing Stepover .125" (half the tool diameter)
It takes about ~20 min or so per piece
I am trying to improve my understanding of the recommended feeds and speeds and I think I must be missing something basic. In the Speed and Feed chart, when I plug in the recommendations for an 1/8" bit I end up with many hours of machining time. The RPM and Feeds make sense to me, but the DOC of .034" seems super shallow. I think I might not understand what DOC is but I was assuming its the same as the Maximum Roughing Stepover.
Depth of cut is the Z depth per pass
Stepover is the XY overlap. Like when you mow the lawn, so you don’t end up with little lines of tall grass because you were trying to save three minutes.
Thanks so much for your reply. So if I understand correctly, the recommended settings for cutting pine with a 1/8" bit (DOC .03", RPM 4500, FEED 72 IPM) would take 15 passes to cut down 1/2"?
I guess I am more used to seeing more depth (1 to 0.5 x the diameter) and a slower feed rate.
Ill have to give this a try and see how it works.
Greg
If you left .05" of material for a finishing pass then I’d say the math is right on. If you didn’t leave any stock for a finishing pass then it should be closer to 17 passes (16 passes and 1 at 2/3rd DOC).
Since you are using Fusion360, I would recommend you consider using adaptive clearing toolpaths?
I’ve been laboriously cutting pockets with regular pocketing toolpaths before, and was always frustrated by having to take shallow passes, ending up with 10+ passes to cut relatively small thicknesses. Then discovered adaptive clearing and the ability to use up to the full cutting length of the endmill, and this felt like a revolution to me. I cut a large pocket in oak recently and reduced the job time by a factor of 10 using adaptive clearing, versus what it would have taken with a standard pocketing toolpath & recommanded DOC per pass.
I have been using fusion and adaptive passes. I ran at the higher speed and 1/2 the diameter of the bit and it ran great. I might try more depth on some test pieces. Thanks!
1/2 the bit diameter is still shallow. For many materials, such as most woods, acrylic, renshape, pretty much anything short of metals, I run 1/8" (3.2mm) tools at a depth of 2.5 to 3X diameter with an engagement of 25 to 40% (0.75 to 1.4mm)
Thanks so much for the help. I will definitely try deeper cuts and see how it goes.
It is taking me some time, but well worth the effort to get my head around how powerful adaptive is.