Step 7: Pour the plaster

Once you are ready mix up some Plaster of Paris or casting plaster (I use Crystacal-R). Dental casting plaster is also good. If your head is made of plaster, then you need to add a mould release agent before starting on the negative mould. Use Vaseline or one of the silicone release sprays.

Plaster for casting is available at most art shops, or craft shops, or off the net. I ignore the fancy mixing formulae, two parts powder to one part water (by volume) will generally give good results every time. One cup of water to two of plaster. Start by getting a quick even layer of plaster all over the mask. If you use a brush be careful not to disturb the surface of the plasticine. I like the messy aspect of it all and get stuck in with my hands and fingers.

Once you have a base of plaster down, start slowly adding to the initial coat. If it all gets a bit out of hand, leave it for 20 minutes to set and then mix up some more plaster and add to the dried stuff. Slowly, slowly catchey monkey. You can add plaster bandage or scrim net to strengthen and support the plaster as you go. Eventually you want a mould at least 3/4" or 20mm thick.

Let the plaster dry for an hour. Another cup of tea and another smoke helps here.

After an hour you can de-mould. Start by pulling away the fence. this will leave a ledge around the upper plaster mould. Grip the edge with your fingers and gently ease the upper cast off the head. It doesn't matter if some of the plasticine comes away with the cast or stays stuck to the head.

Carefully clean away and remove ALL TRACES of the plasticine from both the head and the mould. When fitted back together this will leave a void into which will go our gelatin. Congratulations, you have just made a two part mould.

<p>I've used this recipe without the honey and it worked out very well.</p>
<p>Is it possible to clarify &amp; color the gelatin? Like, instead of honey, could simple syrup be used to keep it colorless, and food coloring to color it?</p>
<p>I was wondering if there is any substitute for honey, since honey is very expensive. I have never made this, but I think that simple syrup should work perfectly, since all you really need is some kind of sugar. But you would have to make it a very thick syrup I think, to get the right consistency. White corn syrup would be another option. </p>
<p>hello can i use this for make figures of sugar paste??? it is safe with foods?</p>
<p>I see no one has answered this, so I will, even though it's been awhile. </p><p>This mixture would be food safe, since there is nothing in it that you can't eat. If you are making cakes professionally though, to be sold to customers, I would double check that to be safe. </p><p>I'm not sure if you mean you want to use this to make moulds to cast sugar paste figures, or for the figures themselves, but try looking up gelatine icing. It is a form of sugar paste that is made with gelatin that is super hard when it dries and lasts forever. Not good for figures you want to be edible, because it's too hard, but great if you want to create sugar art that can be saved as a keepsake. </p>
<p>I tried doing this using a lot of videos on Youtube, and I can't figure out what I'm doing wrong. My mixture won't solidify enough. My mix is pretty gritty but its as good as I could get it. I didn't use honey, but what I'm using is GreatValue flavored gelatin with Humco glycerin (skin care product? I think) its driving me crazy I really want this to work. I tried more gelatin than glycerin but that didn't solve it. I want to use this to make molds for small items like rings and coins. Any help here?</p>
<p>I haven't made this, but my guess would be that the flavoured gelatin might be the problem. Use plain gelatine. Also, make sure the glycerine you are using is just straight 100% glycerine, no other additives.....</p><p>I just realized one of the other comments contained an answer for you- don't skip the honey. </p>
<p>Hi. May i ask what function the honey and they glycerine fulfil please?</p>
<p>Hey! This isn't my instructable but I've used this recipe before (substituting the glycerin for corn syrup, though). They both help to thicken the mixture and make it waaaaay stronger. If you just use water and gelatin (4:3 ratio) you will get a good prosthetic but not great quality and it will tear and fall apart fairily easily.</p>
<p>Hey Chloe. Thanks very much for the reply. I always like to know why I am doing what I am doing! Due to honey being rather expensive, would one be able to substitute it entirely with glycerine? I would imagine that the colour comes from the honey too but that can easily be replicated.</p>
<p>I'm thinking that it would work. I haven't tried it quite yet but I will eventually. If you do, you might want to use slightly less water, from my experience honey is less runny than glycerine or my personal preference of corn syrup.</p>
Hi! I mix 300ml gelatin, 200ml glycerine and 100ml water. Haven't had any problems with it at all!
Sorry it's 300ml glycerine and 200ml gelatin
<p>Glycerine is not a replacement for honey and it's not even close. Honey is mostly a sugar mixture and getting closer to honey would be molasses and corn syrup which are also sugar mixtures.</p><p>ColtD...don't skip the honey. If you can't get honey, you still need a sugar mixture..at least get some corn syrup. You could probably make something useful with table sugar, but you'd have to experiment. Glycerine is not a replacement for sugar syrups like honey or corn syrup.</p>
<p>Next time I get the chance I am definitely going to experiment a bit. I'm not sure but I do think its might be possible to just to use glycerine (I know it's possible to just use corn syrup, water, and gelatin). I love findign out what wroks and whta doesn't!</p>
<p>Everyone here is smarter than me. You said &quot;fill one small cup&quot; and show a picture of a 2- cup vessel with some crystals in the bottom. Please tell me what size the &quot;small&quot; vessel should be. Nothing about your ratios make sense so far. What about starting with an envelope of Knox gelatine? Thanks. Bill</p>
<p>I see no one has responded to this question, and I only saw it just now. When we use a recipe stating &quot;parts&quot; instead of cups or grams, or whatever you usually use, we mean that we use ONE part of any measurement. If you have a small shot glass, you use ONE shot glass as one part, TWO shot glasses as two parts. Then if you have a huge ten cup pitcher, you use ONE pitcher as one part, TWO pitchers as two parts, this way, no matter how much you need to mix, you always have the right ratio. Does this help? I think the picture was just a random cup, and his instructions are more clear than the picture. Ta! :)</p>
<p><em><strong>You can use witch hazel to blend the edges after applying and you can add make up in your skin tone or flocking to add colors as mixing. Instead of honey you can also add sugar free syrup containing Sorbitol to thicken.</strong></em></p>
<p>Using your technique, I created a gelatin prosthetic forehead for my Adjutant Cosplay (http://www.instructables.com/id/Adjutant-Cosplay-Starcraft-2/)</p><p>. It worked really well and I got amazing reactions to my costume! Thank you</p>
<p>Can you use Vegetable Glycerine for this?</p>
<p>hey, first of all thanks to providing such a simple and cheap method! </p><p>I've got one question - is it necessary to use a microwave? or can i also heat it up in a pot on the stove? </p>
<p>My questions are:</p><p>1. I am trying to make this &quot;jelly&quot; as a jelly in a mould for the show Oliver.. how long will it last and any hints on how much to use?</p><p>2.Does it need to be refrigerated after each show?</p><p>BTW I added cochineal colouring to the mix and it looks great :)</p>
@ rmagnificent: <br> <br>Not sure if marshon will be responding. If you don't mind, I may be able to help. First off, I want to tell you that I am no expert. I've just been learning as I go. So you may want to confirm any statement I give if it doesn't sound right to you. 1. Honey. I believe he uses the honey because it gives the gelatin a translucent appearance and color that more closely resembles natural skin. 2. I've tried using liquid latex on my masks in the past and I've had problems around my mouth, eyes, and neck, where the most movement occurs. I now use Pro's-Aide or medical adhesive. It works great, but that stuff REALLY sticks to your skin. If you use it, definitely get the remover that goes along with the particular adhesive you're using. Also, these adhesives don't allow much time (if any) to adjust after you apply the prosthetic. When you stick it, it's there. I prefer Pro's-Aide cause I just apply it and pretty much forget it for the rest of the night. Hope this helps.
<p>Sorry it's taken me a year to thank you for the advice. I fell off the face of the planet for a little while there, haha.</p><p>I tried Pro's-Aide, and holy moley! What a difference. Thank you so much for the suggestion, I'll never have to deal with Spirit Gum ever again! I see what you mean about getting the remover though, this stuff is no joke.</p><p>Thank again for the advice, I really do appreciate it, even if it takes me a year to say so. Happy creating! &lt;3</p>
<p>I cand breed lookig at dah pitchuh</p>
<p>I love that you put this up. So let me thank you for that first. I just wanted to know if it were possible to add some flesh colors to any of the mixtures instead of applying it to the prosthetic. If so, how would you go about doing it?</p>
just made a block there with this recipe. Many thanks, I'd previously tried a recipe from a prosthetic makeup artist's website and it was carp compared to this, well done. Only thing is, I think I made foamed gelatin without a blender since I started with everything in the bowl... Might follow your instructions next time and see what happens ;) Keep up the good work, and I want to see that prosthetic in use!!
I have seen this recipe before but with a food colour instead of the honey. What's the benefit of using the honey please?
When using the plasticine will the plaster pick up more details sculpts as the 'ible uses a pretty simple design?
Hello! First I'd like to say great instructable, and thank you for showing us this versatile technique. I actually have two questions for you. <br> <br>1. You mentioned using honey in the gelatin recipe? I've made gelatin before simply using glycerin, water, and raw gelatin. Is honey a super awesome ingredient I've been missing? What does it do in the formula? <br> <br>2. As far as adhering the gel (for a face prosthetic) is it possible to use liquid latex? Sometimes, for whatever reason my bod doesn't react well to spirit-gum. <br> <br>Thank you so much, and happy crafting!
This is great, children who want to play various roles can get their moms to make them various masks or body parts and then use face painting techniques to liven them up with face painting tools for Sydney from http://www.serendipi.com.au Thanks for the cool tips.
I will be looking around, but do you happen to have a link to any good instructables on making a custom cast of a face or body part? I am wanting to make MANY different prosthetics, and while I have the knowledge and experience to tweak where I need to I have not yet attempted custom casting.
Question... if I wanted to use this technique to mold a gelatin hand, could I use the gelatin cast and pour new gelatin in? Or would I have to fill it with something else first (like plaster), then cast that in plaster, then finally use the plaster cast to pour in the gelatin. That probably sounded confusing, but let me know, thanks!
I'm not completely sure what it is you are asking me. You cannot make a skin cast using hot liquid gelatin. Essentially it's toffee and would result in third degree burns. <br> <br>To make a gelatin hand, you would need to make the master mould from Alginate and plaster, then cast your gelatin in that.
NICE POST!! <br>Question: do the blending edges curl up like foam latex? does the gelatin require powdering to prevent curling?
Glue right up to and past the edges then powder the join. I've not had my gelatin (or foam) cast curl excessively.
Hi there again! <br> <br>Do you apply something special on the piece before of after colouring it? Everything I tried on gelatin prosthetics (powder, RMGP, foundation, etc.) tends to smear. <br> <br>Thanks a lot for this wonderful instructables!
I always talc my casts first. This helps to reduce tack and helps the make up 'stick' a bit better.
Hi Marshon! <br> <br>I tried both stuff and had excellent results with the basic mix, but I can't make thin edges with the foamed stuff even after having warmed the molds up, which helped a lot with the basic mixture. Have any clue for me?
<br>woooooooooooooooow !!
i have had some issues with this step. <br>at first i was using a plaster life cast, with a clay prosthetic, and cooking spray as the release agent. unfortunately the plaster (having not been sealed) absorbed the release agent and all was lost..<br><br>did another life cast and tried again, this time sealing the plaster and applying a release agent... and the plaster came off but it was cracked and un-usable. i was able to save the clay prosthetic..<br><br>so i realized that i haven't been making the clay fence or making the plaster thick enough.. and i shall try again!!!<br>
excellent work
Heeeey Marshon =)<br>Greetings from Uruguay.<br>I cannot beleave i found that page yet.<br>Your 'able is amazing, thanks for share.<br>Im excited with this, i've bought today<br>Sorbitol (5L), distilled water (5L), Pure Glycerine (5L)<br>and 500 grs of Gelatina Oro (Gelatin Gold) :\<br>But the package dont say nothing about bloom.<br>Can you tell me in what places can i buy 300 bloom Gelatin?<br>Thanks =)
...<br>Hello :)<br>Well, i can&acute;t wait ... i had bought gelatina food grade ...<br>I got the basic mix ready, but im having problems to find<br>places to buy &quot;spirit gum&quot; or similar, but i have &quot;teeth glue&quot;<br>this work fine i hope.<br>And problems to find fiberglass head :(<br>But have another question.<br>I have mustach and beard what about melt the mix and<br>put it directly on my face and other body parts?<br>Its hard to remove later?<br>Thx Marshon!<br>
...<br>Aaaaafffff sorry Marshon<br>If put the basic mix direct on my skin what type of non-toxic paint<br>can i use to try to change the colour of this to matches with my skin colour<br>(when the basic mix is liquid yet)<br>Thx !!!
You cannot put the liquid straight onto your skin, it must be cast first. Use ordinary make up, or face / body paint to colour it. This is all in the 'ible. You need to read it first.
...<br>Yep, i did it (read the 'able).<br>Just something hard to understand (for the language).<br>Thx for all =)

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Bio: Untidy, disorganised and a bit silly. I am a photographer, artist, body artist, sculptor, prosthetic maker, model engineer, and general idiot who likes making stuff ... More »
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