I bought this eagle kit from CIC Workshop, which is made out of ColorCore HDPE Plastic. I’ve had mixed results. If you’ll notice, the close-up photo has a lot of “fuzzies.” The bit was new. I’ve tried cleaning up with a toothbrush and wire brush, but this is about as good as I can get it. Does anyone have any tips or tricks when working with HDPE?
Thanks,
Roy
The most obvious solution would be to use a downcut bit.
I definitely recommend these bits from Cadence Manufacturing & Design.
Further to that, I would pick an “O-flute” type bit and work on your speeds and feeds; wood and plastic are really different.
When I cut polypropylene I always used slow feeds and speed. In my case the router was on the lowest speed and feed was set to 20 and while I was cutting I watched for any signs of melting and or fuzziness and reduces the feed by 10% until it was a smooth cut. You can also do a final pass and remove .005 and really slow this final cut down and have the option to increase the feeds if it is cutting smooth. I used a 1/8 down cut bit and have had good results.
I haven’t tried this yet, but try using a small hobby hand held torch on a spare or waste cut and see if the heat will do anything to the fuzzies it may embed the color fuzzies in the white sections and do no good but it is an idea to try.
Anthony
I found this website on HDPE and cutting
this is from the page above
Key Features & Benefits:
Engravable Cap Layer: Cap thickness typically .050" (check depth before cutting). CNC users often cut 0.075" to reveal the core color with clarity.
CNC Optimized: Engraves cleanly with 30° or 60° v-bits for a crisp carved effect. Use sharp solid carbide bits (double o-flute or down-spiral) for best results.
Anthony
Speed Recommendations:
V-bits: 20,000 RPM at 150 IPM, 0.1" depth/pass
1/8" bits: 16,000 RPM at 80 IPM
1/16" bits: 15,000 RPM at 60 IPM
Always test settings with your CNC machine for optimal performance.
Scraping with a fingernail edge of an xacto blade may help.
I typically use 8000 RPM on my 1/8” bit.
I have not tried V Bits on it but will try on some scrap.
When the central color is darker than the outer layers getting a nice surface on a pocket requires testing. I use the 1/8” upcut at 8000rpm.
I did not like the pocket surface with the O Flute bits so those are reserved for cutting.
Maybe using the O Flute to cut the majority of the pocket and then another pass with the upcut bit at a super shallow depth and inset slightly would work but increase the runtime.
If the central color is white or some other light color that is less of an issue.
Usually, just wiping off vigorously w/ a micro-fiber cloth removes all those.
I use a cheap deburring tool to clean a lot of my hdpe edges.
You can also use a torch in really small passes. Too much heat will bend the plastic and you’ll change the shine on the plastic. Quick passes can melt the fuzz great but I’d recommend practicing on a scrap first.
Thank you for the reply! I actually was using an 1/8" downcut end mill. Additionally, the bit was new.
What can possibly go wrong … Roy + Fire = 911! LOL
All kidding aside, thanks for the suggestion. I may get to that point!
Interesting … I was running at 18,000 with a feed rate of 100 for the 1/8" end mill.
Will, apparently, I’m not “vigorous” enough! Trust me - I’ve tried to the point my tennis elbow is kicking in1 haha!
Thanks, Mark! I haven’t used a deburring tool before. Will it work ok on plastics I assume?
There’s minor differences between the ones made for plastic and otherwise. I kinda just found my favorites when I bought a pack. All of them work.
I just bought a deburring set and didn’t pay enough attention. All the blades are the same. They seem kinda large, I will give it a though.
So far, I have exclusively been cutting signs out of ColorCore material and am not getting edges like that. I am using a 1/8" spiral up-cut bit from Amana Tool, part #51411-K. It makes tons of little chips, but the edges are reasonably clean. I picked up the sign making at my job from a volunteer and have just been using the settings he had been using, so I am not sure what kind of trial and error woes he had.
What speeds and feeds do you use and does it make an acceptable pocket surface. In my experience any central color other than white ended up with a chalky appearance with the O-Flute bits and if the speed was too high. It would look great when wet but when dry it looked chalky.
I could not find any way to actually clean those surfaces up.
I use the #102 at 8000 RPM and am happy with the surface but it does leave the fuzzies.
Roy,
Okay I give up. How did you stick the layers together? HDPE doesn’t like glue. I’m kinda baffled.
Kevin
