By riplash2008
HSMA speeds and feeds with plastic and O-flutes
Hello, I have a few ABS and Acrylic cutting projects coming up, and I was looking at the tool paths and speed and feeds. Most of the toolpaths are slotting toolpaths and when I enter the tool geometry and choose slotting I get a real small depth of cut. About 1/5 to 1/10 what the Manufacturer recomends. If I put in DOC equal to the Cutting Diameter, the chip size and therefore the feed rate goes way down. The chip size goes to from 1/4 to as much as 1/16 of what the manufacturers recommend. This happens in FSWizard Online and HSMAdvisor.
Has anybody else encountered this problem or know a workaround? I will post a screen shot shortly. But I modeled a Harvey 878308 1/8" O-flute .5" Length of Cut because they publish slotting data for hard and soft plastics. For Slotting Acrylic at 1 x Diameter Depth of Cut (and of course 1 x Dia axial or it wouldn't be slotting) They recommend 0.0043" IPT and HSMA is giving me 0.00099.
I got similiar but not exact results on FSWizard.
Thanks,
Ryan.
Eldar Gerfanov (Admin)
Hello,
HSMAdvisor doesn't yet have support for O-flute router bits. So the suggested DOC and feeds would be smaller than what manufacturers suggest.
One way to avoid it is to use the HP/Roughing End Mill too type and move the Productivity slider all the way to the right.
Best regards.
riplash2008
Okay, thanks for the feed back and tips. On Friday evening and over the weekend I played around with this. I played around with 2 and 3 flute end mills too. Choosing different plastics keep giving me really small chip load, and I would melt plastic to the end mill if I ran it that slow.
I ended up choosing Roughing End Mill and Moved the Production Slider to the right until the chip load matched the data for the cases that the manufacturer provided. I Then kept that setting and plugged in the geometry of other brand end mills that didn't give that exact case, but compared it to the cases that the other end mill manufacturer do publish and it was resonably close.
I didn't have all the plastic end mill data on my home computer, so I will investigate more today at work. So far Leaving S and F at 100% and moving the Performance Slider to x 1.375 gives me results very close to what the other End mill manufacturers recommend for profiling and gives me reasonable straight line slotting starting points -- which is what the other manufacturers don't give.
Thanks,
Ryan
MikeHorton
I don't have much experience with plastic machining these days. I would think you would want to leave the slider centered since you aren't trying to use the calc to balance the parameters. I could be totallu wrong here, but I tend to adjust my S&F sliders accordingly. Do you input the recommended SFM and CPT also? I have yet to get the chance to try out the new toolin available for plastics these days. Back in the day I always just grabbed the sharpest 2 flute HSS endmill I could find, max out the spindle rpm's and went from there. The machining advisor cal on harvey's site suggested 18,000 RPM, 88.0 IPM, that's 589SFM and .00488 CPT with 1xD for Ae and Ap. I came up with something close to start off with.
Any insight on how this went for you? Thanks