Getting a cleaner edge with HDPE?

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tra
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Joined: Tue Nov 05, 2013 1:27 am

Getting a cleaner edge with HDPE?

Post by tra » Sun Jul 13, 2014 2:46 pm

So I'm cutting 1/16" HDPE with a 1/8" two flute end mill and this is the edge I get. I've played with the spindle speed without much luck. Would cutting direction help? Faster or slower feed rate? This was at 20IPM.

http://i.imgur.com/9kwEQLd.jpg

WillAdams
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Re: Getting a cleaner edge with HDPE?

Post by WillAdams » Sun Jul 13, 2014 2:54 pm

Here's what the wiki has: http://www.shapeoko.com/wiki/index.php/Materials#HDPE
A further note: "With HDPE you want to use conventional milling. It does leave a fuzzy, stringy edge when you use climb milling."
http://www.shapeoko.com/forum/viewtopic ... 17&p=15414

Slower spindle speed, faster feed and single flute bit should help.

I rub the pieces w/ a clean towel and take a swipe w/ a plane to clean up any edges which warrant it.
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
Nomad 883 Pro #596 (bamboo)

ZachKaplan
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Re: Getting a cleaner edge with HDPE?

Post by ZachKaplan » Sun Jul 13, 2014 6:01 pm

We did some tests at Inventables and these settings worked successfully:

DIA = 0.0625
Step over% = 60
Step down = 0.045
Spindle Speed = 12,000
Feed Rate = 60
Plunge Rate = 30

DIA = 0.125
Step over% = 60
Step down = 0.062
Spindle Speed = 12,000
Feed Rate = 60
Plunge Rate = 30

Woodworker
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Location: 5 miles north of Benson, NC

Re: Getting a cleaner edge with HDPE?

Post by Woodworker » Sun Jul 13, 2014 6:05 pm

You will have to secure the material differently but a down spiral bit should reduce the fuzzies. Since this is very thin, clearing the chips should not be an issue.
BRuce - SO2 #4798 - IC's Z axis upgrade, customized Z rail and Z motor mount, spindle Dewalt 611

KevinB
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Joined: Sun Mar 09, 2014 2:01 am

Re: Getting a cleaner edge with HDPE?

Post by KevinB » Sat Jul 19, 2014 7:31 pm

are you using a spiral or straight 2 flute endmill?

I just recently cut some new spindle mounts out of HDPE and with straight 2 flute endmills.

My spiral mills left fuzzies.

Good luck

Kevin
"The Amount of equipment destroyed is directly proportional to the amount of information learned."
Shapeoko 2

tra
Posts: 63
Joined: Tue Nov 05, 2013 1:27 am

Re: Getting a cleaner edge with HDPE?

Post by tra » Sat Jul 19, 2014 8:43 pm

Thanks everyone. Cutting at 50+ ipm has left me with silky smooth edges.

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