Vulcanizing Molds

[@jeromejohnson3623]

I had another go this weekend with another 4 little g clamps for extra pressure and it was a big success. Thanks for the advise it seems lack of pressure was the problem. I also put the mold halves in the oven at 100 deg C for 20 minutes to soften up the rubber a bit before doing the clamping. I'll try and take some pictures next time i do it and post them up somewhere for anyone whose interested.

[@breyerhorsecraxy]

Heya! Just wanted to say I found this video and the previous one very helpful. I recently got into pewter casting on the industrial scale, and we're looking at making molds of custom designs on a vulcanizer machine. The tips and tricks for how to gut the gates and vents was very useful, I'd been having a hard time trying to find the information. Thank you for sharing how you do your work! I still have yet to find resources on what kind of materials can be used for making the masters. I do sculpture out of sculpey clay, but I have doubts it will be able to withstand the pressure of the vulcanizer machine, which leads me to wonder if I should look at making some single-pour molds for single-casting to make some initial pewter metal Masters.

[@roynajecki1100]

Long out of print, the Principles of Centrifugal Rubber Mold Casting by Gonicberg and Ritch is a great resource. Over a decade ago I learned the process from one of the contributors of the book. Your master must be able to withstand 300 degrees F. to work in the vulcanizer, otherwise it will deform. J_B Weld, a common epoxy found in hardware stores and home center, works great.

[@rhyflermaerch]

I purchased it from, I think, tekcast. It broke the second time I used it. However, since I am pouring pewter into the mold it was easy to make a pewter copy of it. Used that same pewter copy to make hundreds of molds since. If pieces are larger and won't fit between the form and the side of the mold then I cut the center channels byt hand.

[@rhyflermaerch]

You need the pressure on the mold when vulcanizing. Mine insets so that I can put that pressure on it. If you can tell in the video i never quite get it all the way in, which means its exerting pressure. You just need to make sure whatever is in your mold can take it. A common practice is to carve out divots so your figures aren't squashed when you tighten it down. I use the screws to get it tight and then the c-clamps to really hold it in place.

[@rhyflermaerch]

Silicon takes longer, or can, to vulcanize, and won't last as long. However, it won't ruin the masters and can survive more undercuts. Are your masters really small or thin? It might be best for you, if so, to have an inset so you can really clamp down on the mold. If your masters are fragile you can carve out some rubber beforehand so they sit deeper and won't be smashed by the two halves. I will add this to my next video.

[@rhyflermaerch]

@minitzonthesun I get the mold blanks from Conquest Industries. I think they are $18-20 a set of halves.

[@rhyflermaerch]

Not a silly question at all, the entire process is complicated from start to finish. When heating the rubber expands and hardens. It flows around the masters and makes the cavities. I use simple talc to keep the two halves from melting together.

[@fuelban]

Very interesting video guy, I was looking for something completely different ( How to vulcanise on to stainless steel} so I can stop flux leakage on my HHo Plates... when I came across your video, very interesting stuff. Really enjoyed watching it.. thanks. Thom in Scotland.

[@Moloch1038]

Thank you very much for taking the time to create and post this videos! Very helpful and inspiring. I was wondering , and this is probably a silly question, but where do you get the "center form"?

[@rhyflermaerch]

Just this one. Its fairly straightforward. Make sure you have a metal can that can take the pressure and cook it. You need to make sure you have some type of mold release between the two halves so they don't become one piece. I use talc.

[@rhyflermaerch]

@kmorfa Um, I call it a gate former. I am not sure its actual name. You can buy them from tekcast or conquest. To be honest for the first few years i cut all of the gates by hand. I only recently bought some formers from tekcast. They broke after a few molds, but since I am pouring pewter into the mold anyway I get a copy of it each mold. I just cleaned one of those up and use it since it won't break like the originals.

[@BlackBonesRock]

cheers, great video, it made me decide to build my own spin casting machine, the biggest trouble for me is finding a cheap mold frame (even having it custom made...) and the rubber here in Italy (it seems they only have silicone around here). How thick are your rubber discs? the ones Conquest sells are 1/2 inch per side, but yours look thicker, am I right? is the Rubber you use the PR-2? I'm going to write them soon and this info would be very helpful. you rock.

[@BlackBonesRock]

yeah, I'm going to vulcanize in my kitchen as well, and my lady wouldn't like it to smell like a rubber factory... so the only difference between natural rubber and silicone would be the smell? to get this straight before I hire some dude to make me a frame, in total your rubber disks are an inch thick, is the inside of the frame the same height or a bit less to ensure a little more pressure on the disks? do you just press the minis in the rubber by hand? thanx for all the help!

[@gilliardcassolgilli9368]

you have another video explaining about the process cooking the rubber?

[@rhyflermaerch]

Spin casting resin could work the same way as this. You can also do drop pour/gravity casts as well. Those don't require machinery of the same scope!

[@ianmageking8977]

Out of curiousity, does this method of vulcanizing molds allow for plastic or resin miniatures? If not, what would you suggest for turning a plastic figure to metal, in order to use this kind of mold?

[@jeffbenefiel180]

I'm so surprised you're molding at such a low temperature. Also, tin masters? I do jewelry molding so all my masters are usually at least sterling silver so they can survive the abusive temperature (the latex or silicon I use requires much higher vulcanization temperature). I guess you learn something every day, I was under the assumption you guys used bronze masters.

[@seanmaster]

May seem like a silly question, but when you set the pieces in and put the second layer of rubber on top, are the indentations made from tightening down with the c-clamps or is it from the rubber melting in the oven to encapsulate the details? If the latter, what prevents the 2 rubber discs from melting together? Is that what the talc powder is for?

[@jeromejohnson3623]

I got a mold frame and have tried to copy your process a few times with varying failures. Although the rubber vulcanises it doesn't seem to flow into all the gaps and often leaves a rounded lip where the 2 mold halves meet. Did you have to chew through the mold blanks refining the pressure etc when you first started out and do you ever encounter these symtoms?

[@xnetshadowx]

Bro, awesome video. I started to make some casting on green stuff, for helmets and guns and different chest pieces for my customarmy, now if they are gonna be resin made, how do i go about doing ths whole process?

[@chacha2000ar]

Hi I am in the same subject as you .. trying to fabricarme the tekcast a tire type. and saw it with screws and presses can give pressure to the flask and it is not so complicated! .. I see by what you say that you needed pressure to the gums or the molds will mark vulcanizaste .. well .. where you put the flask in a kitchen oven? .. so? .. if I can pass that data I would greatly appreciate it .. if I can help .. I would gladly do from designs to electroplating

[@KoEDeath]

I'm interested in making my own molds, I'm curious where you get your original pieces do you actually carve them yourself or do you use existing pewter models you can get from stores to do it?

[@nikolanaclerio3885]

Sitruc hi i can make any piece you want in a heat resist resin made in 2.5D or 3D for more information contact me At [e-mail]

[@rhyflermaerch]

I didn't film the step where I pulled the masters out of the already cooked mold. Its a long process and I couldn't film it one-handed. Metal masters survive and can often be used again to make more production molds. Sculpted things might crumble and come apart and need to be picked out of the cavities. That's why i use softer silicon rubber for sculpted masters. They survive the process.

[@station0075]

I am wanting to do this myself. I have a few questions though. What is the dimension of your mold can? Trying to figure out how big I would need for a 12" diameter disk. Do you have a picture or video of your pulley for your machine? Thanks and loved the video.

[@keithgell8913]

Great tutorial. Question: You say cook for 320 degrees for 2 hours in the oven. 320 degrees fahrenheit? or centigrade"

[@chacha2000ar]

Hello .. I see that we are several people who are trying to understand the same .. I also am going to give heat to the mold in the oven in my kitchen! .. Tell me if you did well and I have the same question as you. . the interior has to be more tall guy that molds to give more pressure or not? .. you know that? .. I smelting and electroplating any help at your command

[@gambit1001]

Nice work! These videos are amazing! Do you create the original figures yourself that you use in the master moulds? If you do, can you make a video about the process of making the models?

[@rhyflermaerch]

I get them from conquest industries in California. You can try tekcast, tiranti, and probably ney metals!

[@thornevladd]

Awesome work I must say but I have to ask. I've looked for months to find these disks in the uk and us for these disks and I can't seam to find em could you point me in the right direction ?

[@keithgell8913]

@rhyflermaerch How did you cut the steel pipe. What was the inner and outer diameter of the pipe? What did you use to drill into the pipe to make the holes?

[@rhyflermaerch]

@easypeasy2 F! I also then let it set and cool, so it cooks for a little longer.

[@chrissilliker8633]

I love this. Im looking at doing it but dont know where to find the mold can thing can you point me in the right direction ? Kee up the amazing vids

[@rhyflermaerch]

Hey! I released a vid a couple weeks ago showing both of my molds cans in a little more detail. The one is this video was made by hand. A 9-inch chunk of pipe and some sheet steel. The one I use now was made by TEKCASTERs, but they don't seem to make it anymore. Any beginning metalworker can probably make the can in this video without a lot of time or money!

[@chrissilliker8633]

@@rhyflermaerch thanks so much ill check it out. Keep up the awesome vids

[@RivynPlays]

So when the mold is cooking the parts you put inside just sink into the "melted" rubber and set when you leave it to cool? I'm just trying to see if I understand it right

[@GeorgeMichaelArt]

Great video and thanks. Who is your supplier for your molds?

[@BlackBonesRock]

last thing, while the rubber vulcanizes, does the frame have to be air tight? are there risks of leakage?

[@Frykin]

what happens to the original figures you used? do you take them out before baking the molds or do you leave them in. Just as you split the mold there was no sign of them.

[@ashwynn4177]

Please please could you tell me if this can handle molten aluminum? In my country I don't have access to pewter. Thank you

[@stvalmon]

Thanks for the instructions! You can link to the store where the purchase rubber wheels for forms?

[@nobackhands]

Great show. Where did you find the vulcanize rubber for the molds? USA

[@rhyflermaerch]

Conquest Industries in California

[@kritichadha2176]

Hi, how long should we leave the rubber after the 2.5 hour cooking to cool down? should we remove it from the vulcanizer or let it cool inside it only.

[@roynajecki1100]

I remove the vulcanized rubber right away to cut the spokes, gates, vents, etc.while the rubber is hot, nearly too hot to handle. Very warm rubber makes it much easier to cut. Don't scrimp on blades: use a new or nearly new blade (I use scalpel type blades) when cutting rubber. I don't use an oven, but a vulcanizing press which heats the ring, platens, and obviously the rubber inside. The press uses a bottle jack to create pressure. The rule of thumb is one hour of heat for each inch of mold thickness. Longer time won't do any harm.

[@bosterinho]

is there anyway to use the vulcanizing molds without using the spincasting machine?

[@rhyflermaerch]

Are you using organic rubber or silicon? It does sound like not enough pressure. Can you get me pictures of your setup?

[@himbe23]

I really want to get into this type of model making. So I want to know where do I start? what all do I need to get to where you are at? What all do I need to learn to do this? thanks so much!

[@nikolanaclerio3885]

Westleigh Medlin hi all the machines you need i could build for only 50000 $ from molding making to galvanic cover also i can give a capacitation course

[@matthewbrasfield3563]

How deep is your mold can? I see the gap when you had the lid clamped on. I assume you had a 1" thick mold blank. So with your mold can on, there must be less than a 1" space in there. How much space is it?

[@matthewbrasfield3563]

I found this info in the comments on your other video. For anyone curious, here it is: "Its an inch deep when closed, but the cavity is an inch and a quarter. The top has an inset so it seals nicely if you can't get it all the way closed."

[@bobmohney5817]

​@matthewbrasfield3563 I realize this is an old post, but I was wondering if you could tell me how much of an inset there was on the top. I know the ring was 1 1/4 so to get some pressure im sure the inset was more then 1/4" . Did bottom cover have an inset also? Thanks

[@matthewbrasfield3563]

@@bobmohney5817 I have my own mold ring I use. The total depth is 1.5". I use 4 plates (2 for each top and bottom) where two are insets that are 1/4" and cover plates that I clamp down so they push in the inset plates and apply fully direct pressure to rubber. I even have a 1/8" plate that I sometime use to replace one of the 1/4 plates if the mold is a bit thick. Basically I found that you want the insets to be as recessed as possible so the rubber doesn't run out when vulcanizing. But you don't want both the cover plates flush with the ring or else you likely don't have enough pressure on the rubber.

[@bobmohney5817]

Thanks for the info. Just a couple more questions. How thick is the wall on the ring and are you still using c-clamps.

[@matthewbrasfield3563]

@@bobmohney5817 1/2" wall and 4 c-clamps

[@rhyflermaerch]

Maybe! It depends on what material you use for your masters. If I can't do it I can point you toi someone that can.

[@rhyflermaerch]

Would love to see images! What machine are you using for casting?

[@BlackBonesRock]

thanx for everything, can't wait to see your next video!!! Cheers!

[@jeromejohnson3623]

I've got a tiranti centricast machine with some plates I had made to fit 9" moulds

[@keithgell8913]

I have been asking the price for 11" moulding can, I have need quoted at over $1,500! Where do you get yours from?

[@sonuverma2796]

your mean 600 to900 rpm, but tell me how much fix rpm required for zinc jewelry casting. because I make machine same to same like your machine. but not properly casting in die. only runner are casting and not design of jewellery not casting. it's only light liars coming in some pcs of design, so please guide line me how much fix rpm required for zinc jewelry. my machine motor 1450rpm , and I used 6 inch pully in machine saft use and 3 inch pully use with motor. then how much size of pully required for perfect zinc jewelry casting

[@minitzonthesun]

Where do you get your organic rubber and how much is it?

[@rhyflermaerch]

320F and two and half hours. Silicon can be lower temp but cooked longer.

[@WargamingHistory]

Very nice tutorial! cheers Matt

[@rhyflermaerch]

Some I do and some I don't. It is a question asked often enough that I should do a video on it.

[@jeromejohnson3623]

Thanks, I'm using organic rubber and I'll email you some pictures. It's just a 9 inch mold frame from contenti and 4 of the biggest G clamps I could fit in the oven.

[@rytisulevicius4777]

Dude this helped me a lot

[@rogermadruguinha2230]

hi do you use any machine to cook the rubber?

[@madmoosebaits]

Where did you get the mold can?

[@gilliardcassolgilli9368]

how do I cook the rubber? whose temperature should I leave?

[@nikolanaclerio3885]

gilliard cassol Gilli one hour At 3000psi and 300 farenheit degrees

[@stvalmon]

Do not tell where available, such as a steel mold for making form?

[@clinurvet]

Excuse me, my English is very bad and you speak very fast, at what temperature in degrees Celsius or Fahrenheit and for how long to leave it in the oven, is equal to silicon?

[@rhyflermaerch]

@easypeasy2 Mine is a chunk of steel pipe!

[@nobackhands]

where do you buy you disk?

[@sonuverma2796]

How much rpm required for casting

[@rhyflermaerch]

You want 6-900rpm

[@gilliardcassolgilli9368]

qual o processo que faço para cozinhar a borracha?preciso de maquina para isso ou não?

[@wilxavier561]

Estou com a mesma duvida

[@DiMoNico1981Swe]

This would be dream to have home.. I have small collections of "Goblin wolf riders, army from 1990.. And its impossible to find any more, but this make is possible to make them agin =):.

[@rhyflermaerch]

Also, my mold frame was cheap because I have access to a machine shop.

[@johnbearross]

Nice job, sir. Best, JBR

[@rhyflermaerch]

Nope, each side is a half-inch thick! I thought I used the PR1s, now I have to check. When I order I just say hi to my guy and tell him I need 10 more mold sets. Haven't called them by part number in years. There is nothing wrong with silicon molds, if you are vulcanizing in a garage or something. They stink, at least when I do it, and I vulcanize in my kitchen!

[@rhyflermaerch]

Not really. If you weren't using the molds in a spincasting machine then you should make a mold in a different way. What are you trying to do?

[@Frykin]

cheers for the reply

[@rhyflermaerch]

I cook the rubber at 320F/160C for 2.5 hours.

[@DonatoVelleca]

So much nice video ... thanks for the lesson ... ;) ...

[@miguelogo1975]

oi henrique, tou en busca de equipamentos pra ese tipo de trabalho, pode me enviar un email asim combersamos melhor, obrigado..

[@rytisulevicius4777]

i bought them from Conquest Industries

[@gilliardcassolgilli9368]

thank you!

[@SuperNickusor]

great great!!! video thanks

[@bosterinho]

Nothing really. I dont lnow how to make molds and I take this ones I have to a guy who does have a spinmaker. But It s too expensive though

[@henriquedalfrealmeida478]

TENHO MAQUINAS BORRACHAS EM GERAL PRA VENDER E MATERIA PRIMA NO BRASIL

[@Akantorz12]

Red HAWK

[@XelaShade]

This is Basically ''Armament Haki'' of Luffy xD

[@FacetsWebs]

rhyflermaerch; Curious if you would interested in doing some work for me, until I can make enough money to build my own equipment? I am a master jeweler and can make and send all the items I would like made in metal models, are you interested? Todd Michael

[@rhyflermaerch]

@minitzonthesun I get the mold blanks from Conquest Industries. I think they are $18-20 a set of halves.