HDPE Milling Gears

I spent the last few weeks working on these parts for a client and enjoyed working in HDPE. It’s a breeze to mill and single flutes devour it. I would recommend you give it a try if you haven’t and enjoy making some parts in it.

I used a 6mm single flute for facing, a 1/8" single flute for the bulk of the milling, and a 2.5mm single flute for getting into the small crevices the 1/8" couldn’t get into. My setup is a Shapeoko 3 w/ HDZ w/ steel-core belts.

Milling Parameters
6mm single flute
DOC = 1.27mm (from stock to desired thickness)
WOC = 3mm (pretty standard as I find a 50% stepover ideal for most soft materials.)
Chipload = 0.175mm (not a problem, could have gone faster)

1/8" single flute
DOC = 4mm
WOC = 1.7mm
Chipload = 0.075mm

2.5mm single flute
DOC = 2.5mm
WOC = 1mm
Chipload = 0.065mm

Photo of my setup (Gator clamps work great)

Video of the milling

Photo of the final parts and endmills used



Bucket of HDPE snow

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Those have to be the weirdest gears I’ve ever seen. :smiley:
Look really fine.

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Will you be melting down the HDPE and recasting it?

OK now that you showed us the gears, what type of usage requires such deep narrow groove? I can’t see two of those trying to drive one another without interfering. Great looking gears BTW.

Yes, @luc.onthego and @CrookedWoodTex, you’ve pointed out the problem with these. They aren’t actually gears, I just don’t know what else to call them. The teeth are not involute and wouldn’t intermesh well at all. My client just hasn’t shared what they’re for and I haven’t asked, although he said he’ll show me what they’re for once he gets them set up.

@WillAdams - No, I will not. Even though I have equipment at work that would let me do that, I can’t do it well enough to my desired tolerances and it’s not expensive enough to be worth my time.

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I wonder if this could be some kind of giant encoder wheels, to be used with a light emitter & light sensor positioned across the edges of the “gears”.

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[quote=“Julien, post:6, topic:19358”]
some kind of giant encoder wheels
[/quote] @The_real_janderson

I’ll go out on the limb and say they are crimpers for the edges of empanada pockets. :smiley:
PS. Its lunchtime here!

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What about a wheel that spins and hits a stationary card to make noise like many of us have done on the wheels of our bike when we were kids so our chopper/banana/Mustang bikes would sound like a motorcycle.

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Nice HDPE work @The_real_janderson!

But… How did you NOT ask? My Sunday is ruined because I need to know. :wink:

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@The_real_janderson - quick question why is you DOC much higheer for smaller MM endmills would you mind explaining, i.e. your 6mm DOC was 1.27 and your 2.5mm is 2.5mm i would have thought that it would be the other way, have yet to mess with HDPE, might be a silly Q so sorry for asking

Jon

@Sherpa
His 6mm was just used to face the stock to desired thickness. That DOC was the amount he needed to remove.

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I know, I know. You’ll just have to be patient and wait with me to figure out what these are for. :slight_smile:

@Sherpa - Yep, like Neil said. I was just using the 6mm to face the stock so I only needed it to go down that far and no further.

1 Like