Acetal plastic

So, a while back I’d asked if there was any Delrin or acetal plastic available to play with. I finally got a chance to play with some. From experience on other lasers I know that I usually have to cut it a bit slower than I do acrylic so I took a calculated guess to start at and it actually worked the first try. I was using some 1/8 inch white acetal that I’ve used on other machines. It cuts like melting candle wax really and though you don’t get really crisp edges like you do with acrylic, it’s much more forgiving to stress and flexing. It’s an interesting material, similar in feel to Teflon. Like Teflon, you can’t really paint it or anything and I’ve only found sheets in either black or white. I’ve not had any luck dying it colors. Being so smooth it would probably be really good for gears or similar mechanical pieces. My favorite thing to use it for these days though is belt buckles :slight_smile:

I knew what my first project should be with it so I had a design all lined up for it. the detail came out as I’d hoped and there was only a small candle like flame trailing the cut as it went along. The sides where the material was being cut very thin curled up under the heat, but didn’t stick to or damage the piece I was making.


the piece I cut out though about the same thickness didn’t have the same issue.

I’d hoped to find some 1 1/2" webbing in this color, but haven’t yet.

But luckily it doesn’t look bad in blue either :slight_smile:

I’ll be doing some more tests with black as well as thicker to see how they work, but I’m pretty darn happy with how this worked out.

For those interested, the design is simple and comfortable and I borrowed it from the excellent folks over at www.grip6.com. They have some beautiful anodized aluminum buckles that are blank canvas’ waiting to be etched.

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Interesting. Sounds like a cool material! And the buckle looks great. Thanks for the link too! :smile: :glowforge:

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Fantastic!
Nice work on the belt buckle!
I am very happy to see this, since it is a great material to make molds for casting resin, and letterpress printing plates, and (as you mention) mechanical parts.

I have a whole box of acetal I have been dying to play with.
Maybe it is time to bug @dan about materials again.
Of course I will need a Glowforge first (hint, hint). :wink:

I wonder how well it engraves?

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Well that’s pretty sweet! :relaxed:

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Ah. I thought that looked like a belt buckle I have (mine is a grip6 carbon fiber). :smiling_face: They were a Kickstarter or Indiegogo I backed last year. Nice in Delrin. I thought about doing it in walnut or cherry but haven’t sourced webbing I like yet.

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So happy seeing some branching out of materials! Wood and acrylic are great but are not really what I expect to use the most, so new materials are always welcome. And the buckle looks great!

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Really want to get my hands on some acetal, expensive stuff, to make the, or a, planetary gear mechanism. I’d make acetal ring gears to sit on on wooden hubs, should work.

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This is great–thanks for sharing! I’ve been eager to work with delrin for all the reasons @jkopel listed, plus a lot more. Great to see that it cuts so well on the Forge.

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I like how the edges of the cut are more rounded and softer looking.

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sweet! cutting boards are also made of delrin and come in a lot of colors. you can find em dirt cheap all over the place. well done!

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As far as I know, most cutting boards are ultra high molecular weight (UHMW) plastics but are not acetal (Delrin is a brand name for a specific formulation). Acetal is much harder and tougher then UHMW, and might even turn the edge of a sharp knife.

Acetal is expensive but worth it for some applications.

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Good to know! I just looked up how to determine what plastic cutting boards are made of and everyone suggests burning a piece and making a decision based on the odor! Even though some of them are pretty toxic when burned haha. Someone said if you file off a little bit of a delrin board it smells like spoiled milk. What a fun compositional test that’ll be!

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For anyone curious, I find eBay to be a good resource for raw materials (which is nice because it sucks for almost everything else). For instance, I buy almost all my aluminum from there (“Stoner Metals”, I think) and there are also plenty of people selling delrin (and acetal). I got a white 2’ x 1’, sheet, ~1/8" thick for around $14, IIRC (which is roughly 3 times the price of acrylic).

I haven’t cut it yet though. A little slower than acrylic, you say? I’ll keep that in mind, TY!

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:heart_eyes:

the webbing I like the best so far is from Country Brook, heavy nylon like this The only hard part is most webbing supplies don’t have a lot in 1.5" for selection. About half as many colors is what I’ve seen.

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especially in the middle of the aisle at target

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A 4’ × 8’ 1/8(3mm) cast acrylic should be around 60$ if you can get it directly from a producer.

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Very nice! Great post.
I just have one question, how does the buckle secure the belt tension? (some of us need it now :wink:)

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You slip the free end over the left (or right) edge and into the slot. Suck in the gut and reach behind the buckle and pull it across. It stays due to the friction and pressure :slightly_smiling_face:

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