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OCC Ceramics: Making a Plaster Mold



well here yeah this is the same piece I just took those pieces off and I want to put that face out there okay so we got the plaster we have our trash right here what we one thing you want to remember do not throw any plaster into the city it will clog we're going to right now is I want to add the plaster until it creates island there's you know you can do measurements one part just two urns that it's much easier just to kind of eyeball it and create an island on 2/3 of an island one-third water so we're going to do right here is here just take this yeah yeah same thing this is just a different kind of this is a for a design that's inside with a clay wall he's going to just look and I can let this sit for about five minutes I couldn't do anything see how the air is just kind of floating onto there right now shake it up in there we're just gonna let that sit for a bit and see how that like 2/3 of violin let's see how much that will go down now the less pleasure used the more coarse the mold becomes okay the more pleasure you've more harder plasterers and less coarse it becomes buddy it's helped them a lot better so we're just going to leave let that sit there for about five minutes the meantime I'm going to show you what you do with a small I got these wooden pieces like run by 5 4 whatever this is and you cut them down to different strips with these hyper middle-class okay and you can just put them down like this over a laughing like this we take some wet clay and we're going to just run along the sides just like this to keep it from leaking because if I go ahead and pour the plaster in right now guess what it's going to leak everywhere it's going to be one big mess so your child what's that it's what because it will be easier to pull out of the mold if it's if this was let's say my child was totally bone-dry right now then I would have to after it would come after the plaster was hard I would put the plaster in a bucket of water and let the play dissolve itself okay we get a little bit more fun and it's so easy to make a mess with this stuff okay so you got to make sure well plug it up and then on this side usually we will like it what I like to do is try it instead of getting the outside corners I just take my fingers and go on the inner part just like that okay come back around here the safety like this exactly but but I'd like to have this part down here because it keeps the thankfully expanding out like that because I got the brackets on the top part I don't have to worry about this okay so now what I'm going to do is see the plaster still it's a chemical reaction that's going to take place with the plasters and what's going to happen is I'm gonna stir it up now and I'm going to get all the chunks out of here let me go to brick stir this all up get all the chunks out of here and normally if I you know like letting it sit for two to three minutes helps the water absorb into the chunks and that way I don't have to stir it up as much just stir that's pretty good what's going to happen is that by starting it you're creating chemical reaction to take place it's going to start it's going to start firming up and as and it's going to clammy and then it's going to get warm and then it's going to get hot and it's going to get real hot and then it's going to start cooling down when it starts cooling down that's what we can start breaking it from it's all my news right now take my glove fill it off okay take my plaster grab it keep on money go up go up that's plenty ok so now what we're going to do is bring that trash back over here drop it right down in here now if you get plaster in these buckets take some wet paper clean it out before it gets hard okay so now what we want to do is is we can use two things we can bang the table like this or we can lightly vibrations like this this will cause a lot of those air pockets in the eyes and different cracker is the air bubbles to come up to the surface and fill in the plasma fills in the cracks but we want to do this a few times no it levels it up now see there's a low leakage they ain't going to really make a difference because it's not pouring out that much and by the time it's going to seal itself off anyhow cause it's going to start curving up pretty soon so what's going to happen where I left this stay here for maybe about 48 minutes and I will just break the pieces of wood from the sides and move it from the this masonite 4 and then start killing out by clear that's pretty much it you know next week I want you guys to have your you know drawings your pieces all done so we can go ahead and make again keep them ramped up here because they're a lot easier to clean up and well then we still have to clean up the molds once it comes out because they'll be undercuts enough to take a knife to a carve away some of those plastic so your pieces from them when we put the clay in there your clay will release a lot easier out okay any question and basically this is good for life I mean you can make tons of pieces from one mold over and over to do eventually little wear out but it takes a long time we want to do is kind of break this from seal here comes right out like that Holton cousin I'm Micah pathing it breaks right off really easy and here this is just going to break off like this so all we're going to do is take a night and cleanup forever and this is a good kind of do it for me a plasters still pretty soft in a week from Al this plaster will be a lot harder it'll be a lot harder to do [Applause] come across here and then here again this play is soft so I can just basically take a wooden tool I don't wanna take a metal tool because I'll dig into the class here which would not be a good idea sometimes you can just grab it will fill right out see just like that and we don't want to dig too hard down into it because we will we can't scratch the image because the plaster is song you see that just pull that right out okay and then with our knife we cut these some undercuts that are going on here what I like to do is just take my time and work out all the undercuts that might form under here so when I apply the clay later they're going to be nothing here that's going to obstruct the pulling on them so this is all undercuts here so we want to kind of go through here and just take it away until till you get a nice line right through here so like here this is undercut here there's an undercut like in here you can see that hot ice itself in there so again you want to come in here and work that all out of it just like that and then next week we can actually come welcome playoff push it down and through here and we'll be able to pull it out within the okay so so I'll go ahead and point it out so how do we do that without destroying the clay piece pull my clay out oh yeah destroying the clay piece we just made oh carefully but I don't wear anything don't worry about the first piece because you'll have plenty more to make after your motor

48 Comments

  1. Xuli Bone Shino

    Very nice tutorial on a one part plaster mold! There is one thing I realized towards the end that could be added!

    Adding a release agent (like murphy soap) before pouring the plaster would make the terracotta piece dislodge almost completely after hardening! Then, you wouldn't have to risk chipping or cutting into the plaster while digging out the clay piece! ^^

    Reply
  2. sam111880

    Great video most important thing i like about this and learned from it. Is layer you buckets with plastic so you don't have to clean them out quickly/right after alot less mess/saves the buckets. Also i like the metal brackets if they are as good as using wood working clamps that would save the need for them and make the resizing of the mold boxes much quicker in setup time.

    Reply
  3. Santino Dipiazza

    I wished there was an undo what I just watched option, Poor souls have probably paid to have this man teach them all wrong… A new generation of the studio potter is on its way…

    Reply
  4. erick sal

    Hi. I need help with a question. I live in mexico and cant seem to find gypsium.powder to make molds. I would like to make slip molds, i understand that plaster is ideal with a gypsium mold being that the gypsium retains the water from the plaster hence creating the slip effect. Unfortunatly down here i cant find gypsium, my question, can i use stone lime powder to make the outer mold? I do have acces to plaster. Or could i make the outer mold from.plaster and the slip cast from.plaster also? I would appreciate a response ty.

    Reply
  5. Fed up With Lies

    What's with the two african women? I don't think they are in that class , to learn, but to make mischief. They have a passive aggressive attitude that is obvious.

    Reply
  6. flavio xavier

    Boa tarde
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    Eu coloco quanto % de dióxido de silío no Quartzo?

    Mim ajudar na resposta dessas 3 perguntas por favor.
    Meu zap 081-9-9143-0380

    Reply

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