Wednesday, 29 December 2010

Molding -casting process step by step.

Ok, here's how i go about molding one of my busts in silicone in order to get a resin cast of it.
                                                                    
                                                                        MOLDING.

1: the finished WED sculpt covered with clear acrylic spray for easyer and cleaner release from the silicone.
 2: The first layer of silicone(100ml) ( RTV silicone rubber for molds). I used a soft brush to apply it and blowed air to it with the airbrush to eliminate any airbubbles. Also added a small piece of elastic cloth mesh to the forehead so that the silicone wouldn't tear while trying to get the cast out.
 3: Second layer 100ml and another piece of mesh. I colored the second layer so that i have control of the thickness of the silicone.
 3: Third and fourth layer(200ml each).Just to give the mold more thickness and durability. i used thixotropic agent to make the silicone paste like and applyed it with a spatoula.
 4:Front half piece of plaster for support (mother mold). I then added vaseline to the edge and applyed the back half. When it was dry i separated the 2 plaster pieces  started cutting the silicone to remove the clay sculpt from inside.


5: Here you can see how and where the silicone was cut. (The sculpt was removed here).

6: Another view of the closed mold.

CASTING.
1:Filling the bucket with 850ml of translucent poyester resin.It's called MPAL and that's it's original color before i add white oil color and catalyst to it.
2: I add that amount of white oil color in the resin. The oppacity or translucency of the cast depends on the ammount of color in the mix. I found out that this is a good ratio.
3:Mixing the color good  first and then adding the catalyst. (10-12g per kg).
4: After the catalyst is mixed very well i hold the mold in that position and start pouring very small ammounts on the face area while guiding the resin with the back of a small brush so that i'm sure that there aren't any major airbubbles traped inside. Especially the ears and facial features.
 5:Then i close the mold carefully and start pouring larger ammounts while rotating the mold with my other hand. I ususally see the bubbles coming up to the surface when i'm doing that and it feels good! :)
 The filed mold waiting to set.
 I also fill these molds with the same batch of resin for the bases.
 Here's the resin's color after about 2 hours from casting. It's now ready to come out of the mold.
And this is the raw cast right out of the mold and mounted on it's base. First i pull the ears off carefully and the rest of it comes out with no effort.I needed both my hands for that so there are no pics:) 
Next time i'll post the process of the painting on a piece like that.

13 comments:

  1. Hey Aris!

    thanks a lot for sharing your mold making Technique, really cool to see how you work.
    I had a question tho....i tried to search for the MPAL translucent polyester resin. Is that a certain Brand? where can i get it
    the creatures you are making are amazing man!! Very very inspiring!!!!!!!

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  2. Aris, this is great! Ill definitely be trying some of these tricks on my next cast.
    Would you use the epoxy spray on Chavant as well? Ive yet to test it out.
    Thanks mate, indeed, very inspiring!
    PS have you considered making a 'Store' page?

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  3. Thank you guys!!
    L7, I asked for a translucent polyester resin and they gave me this one. It prooved to be good for what i wanted it for so i stuck with it. Although i'm sure you can get the same results with any kind of translucent or clear resin.
    Ed, I don't use the spray on chavant as it comes very clean of the silicone. Plus it would stick on the clay and probably make a mess.
    About the "store" page, It's on my future plans .

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  4. Thank you so much for deciding to do these tuts, Aris! Super great stuff. Painfully so, even. :)

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  5. very cool, i love your tutorials. When i work with silicone i do matrix molds to save silicone compared to box molds. I never tried the brush up method, i should give it a shot.

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  6. Thank you guys! I'm glad you found it interesting! :)

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  7. so glad I got to see how you cast this. Thank you very much for taking the time to put this together, I know what a hassel tutorials can be.keep up the great work dude.

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  8. Thanks so much for sharing ,Gnomon must to create a full new series of Creature sculpting works with you Aris:)

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  9. "I usually see the bubbles coming up to the surface when i'm doing that and it feels good! :)"
    This is wonderful!

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  10. great piece,

    Im really new to molding so i have a few questions :)

    First normally do you get the original sculpture out in one piece?

    Another, what would this method be called ive researched into glove molds but they seem expensive and confusing? This method seems easier, also is it really necessary to have a 2 piece mother mold it doesnt seem that you used one here?
    any tips would be greatly appreciated

    love your work ill try to put up a pic of a sculpture im doing right now i have some more questions on whether it can even be molded because of some aspects.

    lol sorry about all the questions.

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  11. I greatly appreciate you tutorials.

    Big Question:: How do your remove the original WED clay sculpture if you only have that little slit in the silicone jacket?

    Thnaks again.

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  12. Hey Aris,

    how do you join the base you molded to your sculpture?

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  13. Nice blog. If you are looking for steel fibre for precast then contact only at Precision Drawell.

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