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Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

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Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#21

Post by mdorazio »

virtualritz wrote: post #19
mdorazio wrote: post #6

Earlier quoted context omitted.

You've got several options here, none of them great. 1) Use a resin printer and print the meta-molds at very high resolution, then lightly sand with high-grit paper or use a gap filling primer paint. 2) Use ABS, HIPS, or another acetone smoothable plastic and vapor bathe the meta-molds (would probably slightly mess up the split lines though). 3) Use a paint-on epoxy to manually smooth out the meta-mold interiors. 4)…

Re.: 1) The latest generation of 'cheap' DLP printers can do 25 micron (e.g. the Phrozen Shuffle). After curing, dipping in resin again or priming and then coating with 2-3 layers with an airbrush results in a perfect surface finish. No sanding required.

Are you actually getting a perfect surface finish that way? My Phrozen Make printing at 20 microns leaves noticeable lines and definitely requires cleanup around support attachment points. I tried doing the second dipping method and ended up with melty details on finer parts of prints. The only thing I haven't tried is sandblasting.

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#22

Post by yetihehe »

jcims wrote: post #15
lurquer wrote: post #11

Earlier quoted context omitted.

The molds are not 3D printed. Rather, the molds for the mold are. The actual molds used in production are silicon, obtained after pouring silicon into the 3D mold-of-the-mold.

FWIW mold for a mold is usually called a pattern

Pattern is the object you want to have produced. Metamold is a mold which gives you mold which then can produce your pattern.

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#23

Post by namibj »

kragen wrote: post #16
opencl wrote: post #10

Earlier quoted context omitted.

The paper authors used FDM machines (Ultimaker 2+, a Stratasys J750, and a Stratasys Fortus 450 MC). But even the cheapest $500-ish resin printers can do 25 micron layers with 50-ish micron XY resolution and it is very very hard to see those layer lines.

FDM machines are almost invariably resin printers; ABS and PLA are the most common resins for them to print in, although others exist. In theory you could do FDM in non-resin materials such as, for example, metals, but I don't know of any examples.

Lost wax casting.

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#24

Post by wastedhours »

candiodari wrote: post #8

But 3d printing is not food safe, so using this method for chocolate molds seems unwise.

Some is, I've seen a few decent examples using an Ultimaker [0] like Dinara Kasko's work [1]

[0] https://ultimaker.com/en/stories/19498-using-3d-printed-shap...

[1] http://www.sogoodmagazine.com/pastry-blog/pastry-chef-articl...

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#25

Post by syntaxing »

It would be great to try the algorithm out if they ever release the code. I've made molds through "traditional" CAD software like Solidworks and the process takes about 30 min. It works pretty well for the typical stuff but I have not tried it with something with a lot of organics shapes like a figurine. The biggest downside about silicone casting though is that its super messy. The costs adds up too since you either need a small vacuum chamber for the silicone or you have to buy the more expensive variant with platinum in it.

Side note: If any one is looking for a lowcost (~$500) "SLA" (it's really UV DLP) printer, you can go for the Anycubic Photon[1]. It should be good enough to make a master pattern without the visible layer lines. A caveat though, the resin based prints are super messy and is a pain to use.

[1] https://all3dp.com/1/anycubic-photon-3d-printer-review/

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#26

Post by kragen »

diablerouge wrote: post #17
kragen wrote: post #16

Earlier quoted context omitted.

FDM machines are almost invariably resin printers; ABS and PLA are the most common resins for them to print in, although others exist. In theory you could do FDM in non-resin materials such as, for example, metals, but I don't know of any examples.

Your parent comment is talking about DLP/SLA printers. Though you are technically correct about FDM being a resin printer, it's not the way hobbyists talk about it.

Maybe hobbyists should say "SLA" if they mean "SLA". This is like people who say "wheat bread" as the antonym of "white bread" — what do you suppose they think white bread is made from? (And it sets them up to be ripped off, as there plenty of manufacturers out there who are happy to sell them "wheat bread" made from 75% white flour.)

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#27

Post by mcphage »

juliendorra wrote: post #5
cannedslime wrote: post #2

Where can I get this?

It’s a research paper so most probably there won’t be any software delivered. Sadly it’s not the norm for researchers to release the code or an user-fronting application when doing computing research (or any research). Open source exist but is even rarer. There’s dozens of very useful and advanced creation tools created in labs that never turned into usable application. In some domains big players pick up on the rese…

> It’s a research paper so most probably there won’t be any software delivered. Sadly it’s not the norm for researchers to release the code or an user-fronting application when doing computing research (or any research). Open source exist but is even rarer.

> There’s dozens of very useful and advanced creation tools created in labs that never turned into usable application. In some domains big players pick up on the research and include it as a feature, but many advances just stay in labs for ever.

I call papers like that "Show & Tell"—it's not science, it's just "hey look at this cool thing I did". Which, yeah, it's cool, but as a paper it's completely useless.

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#29

Post by jcims »

yetihehe wrote: post #22
jcims wrote: post #15

Earlier quoted context omitted.

FWIW mold for a mold is usually called a pattern

Pattern is the object you want to have produced. Metamold is a mold which gives you mold which then can produce your pattern.

Ah! My mistake. Thank you.

Re: Metamolds: Creating ideal 3D printed silicone molds faster and cheaper

#30

Post by virtualritz »

mdorazio wrote: post #21
virtualritz wrote: post #19

Earlier quoted context omitted.

Re.: 1) The latest generation of 'cheap' DLP printers can do 25 micron (e.g. the Phrozen Shuffle). After curing, dipping in resin again or priming and then coating with 2-3 layers with an airbrush results in a perfect surface finish. No sanding required.

Are you actually getting a perfect surface finish that way? My Phrozen Make printing at 20 microns leaves noticeable lines and definitely requires cleanup around support attachment points. I tried doing the second dipping method and ended up with melty details on finer parts of prints. The only thing I haven't tried is sandblasting.

The Make can't do 20micron. It can do about 47 max (or rather, min), I think.

Re-read my post: I was talking about the Phrozen Shuffle which has a different screen/display unit.

Check the FB group for some 27micron examples done with the Shuffle.

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