The beginner's guide to mold making and casting

More info: blog.prusaprinters.org/the-be...
In this video, we'll show you how to create molds and casts of your 3D-printed objects. This opens a whole new range of possibilities, such as small-scale production of custom-made products - like candles or bars of soap. It's not difficult at all and you need only a few basic things.
The sample model was printed on the Original Prusa SL1 from white tough resin, the tool for making a mold was printed on the Original Prusa i3 MK3S.
Original Prusa SL1: shop.prusa3d.com/cs/52-origin...
White Tough Resin 1kg: shop.prusa3d.com/resin/944-wh...
Original Prusa MK3S: shop.prusa3d.com/3d-printers/...

[@KK4CNM]

Pro tip: Use sulfur-free clay. Clay that has sulfur in it will inhibit the silicone from curing properly. Tip 2: You will want to seal the SLA print. That kind of resin does not react well with platinum cure next to silicon. Prints can be sealed using a few coats of a good clear coat. For example, Krylon crystal clear.

[@KikkawaRyu]

A big flex there, using an old printer bed for the base to do it all on aha

[@camilapascual1993]

Wow this is my current dream right here. Making molds for candle and soap making !

[@schedelworld]

Thank you so much for making a concise video with subtitles. This was just what I needed!

[@JulianMakes]

I use my mk3 for making moulds and patterns all the time, it is such an awesome machine.

[@Mr.C-Mister]

DUDE CAST METAL BLADES TO A PERFECT SIZE IN CLAY WTF! THIS IS AMAZING!!!

[@F2_CPB]

Thanks for making this video! I was planning of cold casting my 3D printed beyblades. It's really helpful for me

[@laurispeterisvejs4007]

Still loving my prusa i3 mk3

[@interficiam]

I just print my molds directly: take 3D-object, subtract it from a cube and split that in half. Then print that. The molten wax isn't hot enough to ment the mold, so it works fine to make candles.

[@Alm8hoorOW]

interficiam, what material did you use?

[@interficiam]

​@@Alm8hoorOW I used transparent PETG. I don't think it matters a lot, but with this i could see if there were unfilled areas in the mold.

[@alexalexalexmack]

You may have just changed my life. THANK YOU!

[@allaboutedm8050]

Hi I haven’t done this before so just wondering, when you say ‘take a 3d object’ is that a physical object or something digital on the design software used for the printer? I am looking to make lots of different one sided moulds

[@microfx]

Super awesome video! Thanks man!

[@updnup]

Exactly what I was looking for, thank you!!

[@vincentpernicano3277]

You are a brilliant marketer and business man Mr. Prusa! My hat is off to you for realizing the potential market for this use case of SLA printers!

[@tranhdinhda_bino3259]

Thanks a lot for your video. Now i know the difference between " mould" and " cast".

[@MauryXman]

SIETE SEMPLICEMENTE FANTASTICI, GRAZIE GRAZIE GRAZIE Yuo are too much fantastic , thanks thanks thanks

[@forward3dprinting796]

Fun vid Josef. 😎

[@keiou]

Great idea! 😁

[@grantsbirds1207]

love the video!

[@cakeller98]

Very nice instruction -

[@ivanperez8200]

Awesome!! Should do concrete pots too from a 3d printed mold

[@DwarMeji]

I've viewed many videos like this one using a 3d printed model to cast in a silicone rubber mold for use to cast epoxy, urethane, wax, pewter, etc. Though I've yet to see a video that shows 3d printing of the mold itself from flexible filament to use for casting. This could be a time saving technique.

[@admon1234]

Pretty fun video

[@mlubecke]

Very cool 😎!

[@homeautomationlab1533]

I see the cult of Josef Prusa is progressing nicely, hail to the chief. I can't wait to sit in my bathtub tonight surrounded by little Josef's candles and wash my self with Josef soap.

[@NoMoreBsPlease]

Ohh, this gives me a great idea for 3d printing a Prusa... I meant project

[@constantinosschinas4503]

prusa is a great comedian. first he designs a 35.000 hour, utterly expensive IKEA hack booth, now he is actually printing what you can make in 1 minute from carton. way to go man.

[@somedude2492]

So now there is a Prusa resin printer? Wow

[@joseamirandavelez]

Awesome! And I just need two printers!

[@Zeksait]

Thanks!

[@KaossFPV]

oooooweee someone needs to stop biting nails :p great video!!! love these quick videos

[@flemmingnielsen904]

Nice😀😀

[@cigp]

Nice

[@Aletaire]

Anyone going to comment on how similar the music is to Austin Powers?

[@BurninGems]

Ja baybeee...

[@BAHDK]

no

[@alexalexalexmack]

ahaahaha i totally thought this too

[@Clay20208-Gaming]

Awesome thx

[@blubbblubbblubbish]

Nice tutorial. The background music sounds like someone wanted to rip off the Austin Powers soundtrack, but made it just different enough so that it doesn't infringe copyrights of the original.

[@eliseorocchetti]

Great video! Thank you very much! I would like to know which kind of product is the separator you use

[@OscarTorresWork]

Great video, what silicone material do you use? Looks like it was already prepped and no two part mold solution just the activator really nice.

[@stancutaheart]

Tare, seful pe post de lumanare, e bun cand nu vrea sa-ti mareasca salarul. :)

[@wesbrackmanthercenthusiast4695]

Just print two pairs of inverse molds and cast in that so the print would be the mould that way things like clamps and hinges could be built into the design even cooling tubes to run water through I will be useing this technology in the future for lost wax casting of replica steam locomotive parts and old tractors

[@joshuamiller7231]

I have tried this a few time and hit a few problems. Like it will leak, sorry they just do not get tight like a silicone mold would. Also getting your item out it really helps to have the flexibility of silicone. I have been doing 3d printing to casting for a few years now, and use it for as much as I can but direct to mold has not been very good for me.

[@xmalina]

What about printing the mold with tpu?

[@joshuamiller7231]

@@xmalina layer lines like crazy and it will likely still leak. Not saying it can not be done, depends on the quality of the end product you need and time you want to put into the mold. If your item does not need to be perfectly smooth and shiny then yea. Also you can improve the seal with silicone to slow leakage. SLA and the small layer lines are great for casting but then we are limited by print size ... the joys of 3d printing.

[@MilanRys]

Burn Průša Burn :D Combination of 3D print and casting is very powerful, much faster than only 3D print and the material structure is better.)

[@hackneo64]

Just in time for valentines day...was thinking of a neat gift to make for my girlfriend

[@alextardif]

Totally! Nothing screams LOVE better that a candle in the looks of another dude!!! Offer to bathe her by rubbing Josef Prusa's soap face all over her body and you're in for date she'll never forget!

[@Gr8Success]

you could make her a custom dildo on your 3d printer in ninjaflex filament or you could make a mold to make a silicone one

[@throwawayaccountm1325]

@@Gr8Success I mean...Its possible but.... WTF

[@colinyoung3685]

@@throwawayaccountm1325 He's a romantic.

[@TheRealMisterJ]

I love my prusa, but just got my old Taz working and noticed in Cura there is a mold function that automatically slices a solid model into a castable mold.. Is something like that possible on an mk3?

[@kr15uk]

J S Just add your MK3 to Cura, highly recommend.

[@harti36126]

Hi. I am still new to 3d printing. I have MK3s and use PrusaSlicer. Is there an option in PrusaSlicer to print object in negative, so I can print out the mold immediately? This would be a great feature.

[@martinbudinsky8912]

Aha tak sem utekl ten vesnickej úchyl. :D (tři sestry)

[@arunpanchal7592]

A tutorial on metal casting please from sl1

[@paulmason5543]

Go to m.kzbin.info/door/NC9gjgYrzLfyMQmp31DnjA

[@TGWMS]

Soon

[@benthk3dprt136]

I tought about casting, but it takes longer to cast and requires more expensive materials then to acctually print it. but sure if you want to make candles or soap this is great.

[@jojoposter]

Yeah. When we tried to make 80 copies we evaluated casting as well. But it was cheaper and faster to print all of them

[@jeffdeprey6279]

Think these same steps would work fine if I used Plaster instead of Silicone so I can cast clay?

[@Mr.C-Mister]

This is so fucking awesome! I'm no longer board. MICHAELS HERE I COME!

[@siliciy_]

I made galium tin and zinc prusa figure ;-)

[@mrpancake5761]

can you also cast with melted filament? for example supports that i dont need anymore

[@AnilArya51]

Next is *ORIGINAL PRUSA SOAP* by *JOSEF PRUSA*

[@PetrHosek]

Je to uzel nebo knot a nebo knot a nebo wick ;)) ?

[@oupis1983]

aniž by to byla reklama, ale odkud jste koupili silikon a tvrdidlo? Když už jsme u toho tak i ten separátor :D good job

[@Retyus6]

stačí se pozorněji podívat a na tom kýblu je nápis. Lukopren. Mají vše, i separátor. Pro více infa stačí googlit

[@nobocks]

i know there is some flex for sla, possilble to print directly the mold ?

[@noisycarlos]

I'm guessing it depends on the melting temperature of what you're making. You don't want the hot soap to melt you're 3d-printed mold.

[@Harz77]

I want to make fine casting moulds. That’s my profession, would a 3d printer help to then create a rubber mould that I can pour consistently?

[@juan2617]

I am reading through the comments and my question is only could I do a silicone mold instead of using S LA or resin. Should I use the actual negative as a traditional 3-D print with FDM Printing then put it in creating a mold box and then pouring the resin or would that be too hot it and it might melt the actual PLA o ETG

[@TGWMS]

Nope because you must stretch a mold for correct remove the cast from it and when you have mold without stretching you are not able to put out the cast. And of cause the temperatures of casting material. With those temperatures you melt down the plastic.

[@TGWMS]

Nope because you must stretch a mold for correct remove the cast from it and when you have mold without stretching you are not able to put out the cast. And of cause the temperatures of casting material. With those temperatures you melt down the plastic.

[@1FishinAddict]

All that work and you could’ve printed the Mold itself lol.

[@necromanteion1976]

Wouldn´t it be easier to print the mold ?

[@Marcresus]

Hello Joseph, why don’t you use solid mold directly printed with the model in negative ?

[@dr.orphanic1375]

Super. Akorát já potřebuji odlévat hliník při 800 °C :-D

[@TGWMS]

Forma to vydrží ;-) bude o tom příští video

[@doc.chocholousek3378]

@@TGWMS Tak příští asi ne xD

[@Harz77]

What 3d printer do you recommend? And silicone?

[@bigwurm8314]

Isn't there a reverse model option on prusa slicer to make a mold of it like cura?

[@Prusa3D]

Unless the shape is super friendly for casting, you can't just print the mold. It needs to be very flexible, otherwise you won't get the cast out. - Mikolas

[@carlandre3892]

No one: Josef Prusa: ORIGINAL PRUSA SOAP BAR By Josef Prusa

[@erispe]

If you are printing a mold shell, make it shaped more like the model you are casting, following the contour by a centimeter or two. Will save you allot of silicone!

[@yeetusdeletus650]

or use molding mode on cura

[@cr6925]

Can the SL1 print in different types of resin? Or is it limited to just one type of resin?

[@ImaginationToForm]

Yes. There are ABS-like,flexible,fast curing resins.Long as it's marked as 405nm it's OK

[@TGWMS]

SLA or MSLA technology have over 40types

[@MCRuCr]

Why not print the mold directly? You could also integrate cooling channels to watercool the form and go mass production!

[@TGWMS]

You must stretch a mold little bit to put the cast out I it so that printed one is enough for really simple objects but not for objects with some detail. And of cause you have all print lines on cast itself from mold

[@DougHanchard]

Anyone know of a reputable Canadian supplier of all the chemicals required?

[@timon1463]

Any plans to try something like this with metall?

[@Tommy-pv1vh]

same basic proses but for metle you want to use someintng like sand insted to silicone

[@robertbennett883]

You can do pot metal (low melting point metal like zinc) in a silicone mold . But brass, copper, aluminum, or other metals with melting points higher than about 300⁰ C will need to be done in either an investment (lost pla) or sand cast.

[@TGWMS]

Yep

[@Mike-pz2ov]

When is Prusa XL going to be announced? :)

[@bobabooey8367]

did anyone get that Austin Powers vibe at the beginning?? Yea Baby Yeeeaaahhhh

[@shreygupta1641]

Why not go for mayku formbox instead?

[@MrMoka15]

When I tried to mold a SLA print with silicone the silicone didn't cure. Anyone an idea why this happened? I used Anycubic Resin and Smooth-On Ecoflex Silicone. Do I have to use different silicone or is there a special resin for casting/molding silicone?

[@TGWMS]

You must have 2part resin not that you cause with UV light

[@Dombi3D]

Hi Alex, I had the same problem but than I have found out that Resin prints are problematic with Platinum-cure silicone. I bought than one Tin-Cure silicone and it worked. I am planing to make a video about it in the next weeks because I could not find any video before regarding this issue!

[@TGWMS]

Do you have right set of both parts of silicone?

[@MrMoka15]

​@@Dombi3DI did used platinum cure silicone, maybe this was the problem. Next time I will try another silicone. Thank you for this tip.

[@mikebuckler]

Any idea on the release of the XL?

[@throwawayaccountm1325]

I mean, they said it will be an XY core one with a 40x40x50 cm build Volumen..... soooooo maybe this year ?

[@throwawayaccountm1325]

Never mind.... Next year maybe ?

[@medyk3D]

There is Prusa on fire at 5:23

[@marccretten]

How UV stable are the SLI 3Dprints?

[@josuebetancourt9527]

from my understanding it all depends on the resin, but I think compared to FDM they do decompose faster under use and UV exposure.

[@noahno]

No need to print a mold shell, foam core and a hot glue gun work fine and save time/materials

[@BAHDK]

silicone doesnt need a seperater

[@grogyan]

Lost wax/PLA casting?

[@TGWMS]

Soon

[@canercelikq]

cant we just use ninjaflex to create mould?

[@Anatol.Junior]

Why you didn't just print the casting negative?

[@TGWMS]

Nope because you must stretch a mold for correct remove the cast from it and when you have mold without stretching you are not able to put out the cast. And of cause the temperatures of casting material. With those temperatures you melt down the plastic.

[@thedangerouskid9955]

Or just go to cura and press "make mold"

[@tetsuoswrath]

And when I get that feeling , I want sensual printing. Sensual printing, oh baby , Makes me feel so fine. :{J

[@spawn666reaper]

Why not just print the negative and use that as the mold???

[@MichaelReitsma]

I was wondering that too. Is it not possible to print two halves that you can use to cast candles in? And how to do that? Getting my mini soon ..

[@maxtheswamp]

i dont get it etheir. we print directly molds with channels to release air and pins to estabilish mold parts in accurate position.

[@SenorRu]

Hot wax/soap would warp the plastic, I guess. Alternatively what if you printed positives of the mold and pour the silicone on that?

[@TGWMS]

You can't put out the cast without stretch the form a bit . So when you have mold printed that cast stay stuck inside and you can't remove it from inside

[@privateprivate31337]

How come you can't just 3d print your mold?

[@gioromeo]

Hi, how did you melt the soap in the microwave? Normal soap bars do not melt with microwaves but in the video it looks like you just put soap slices in the oven 🤔

[@TGWMS]

Yep if you have soap for casting then you can melt it in microwave

[@gioromeo]

@@TGWMS Is is a special type of soap? Thanks

[@TGWMS]

Nope it's standard soap that you can use for casting. This soap is little bit different than that you buy in standart store those you can buy from farms, hobby store or some creative stores. It's for casting or making your own soap. Normal soap you must melt on fire with bit of water then you can cast it also ;-)

[@poodlescone9700]

Why would you not just make a negative of your print and print the molds directly?

[@TGWMS]

Nope because you must stretch a mold for correct remove the cast from it and when you have mold without stretching you are not able to put out the cast. And of cause the temperatures of casting material. With those temperatures you melt down the plastic.

[@CalamityLime]

the music sounds weirdly Austin Powers

[@mehrdadhaghighi5140]

Why not just print the mold with the Resin printer for a perfect result and less manual work?

[@pokszymon]

5:07 what's up with those thumbs?

[@oh5148]

I thought resin prints didn’t need supports lol

[@colinschabel]

I don't know how to use a mick-row-wave

[@colinschabel]

Ever make a table candle? You pour the wax on the table, and set it on fire

[@damenevans]

... couldn't you simply print the mold?

[@TGWMS]

You must stretch a mold little bit to put the cast out I it so that printed one is enough for really simple objects but not for objects with some detail. And of cause you have all print lines on cast itself from mold

[@sebamop]

If you print it in two halves, you avoid the modeling clay part

[@julianreverse]

Nope, you won't get a perfect result out of it.

[@TGWMS]

Exactly. You are not able to do perfect half of mold.

[@throwawayaccountm1325]

@@TGWMS you are the reason why i didnt had to write ,,because it would melt'' or ,,because it has to be slightly elastic'' under every comment with ,,why not just print boath negatives??'' . Thank you

[@TGWMS]

@@throwawayaccountm1325 because that's the reason for the same question again and again that question have still the same answer and you already answered it ;-)

[@lukassaiz105]

je smutne ze ceska firma nema video v cestine. to je hanba. a titulky to nezachrani..

[@doc.chocholousek3378]

kolik čechů ty tiskárny koupilo taky bych byl rád za český videa ale časově se to dost nevyplatí nemluvě tom že cz umí jen češi, aj vsechni včetně čechů, takže to je i korektnější k zahraničním zákazníkům

[@bebebe3000]

really?

[@ergosum9416]

Why not just print the inverse of the model? Seems a bit overkill

[@avongil]

Because of undercuts. If your object has undercuts, it cannot be de-molded. A silicone mold offers flexibility.

[@ergosum9416]

@@avongil why not print the mold in two halves with internal supports, and then clear the supports in the same way he cleared the supports off the model

[@julianreverse]

because this is the right way how it's done.

[@TGWMS]

Nope because you must stretch a mold for correct remove the cast from it and when you have mold without stretching you are not able to put out the cast. And of cause the temperatures of casting material. With those temperatures you melt down the plastic.

[@tbone1943]

No need for music here

[@Elektromanyetix]

this figure so ugly please dont make this again!

[@JohnJones-oy3md]

Imagine being this narcissistic.