Seeking Advice on Silicone Glove Mold...

[ajoysisk]

Hello, All:

I am getting ready to finish the attached piece and make a silicone mold with PlatSil 71-11 (mother mold will be of Hydrocal). A reliable source suggested I just do a glove mold, and with all due respect to said source, I keep looking at the piece and feeling dubious that the silicone is going to be flexible enough to peel off over the chin and hair after leaving the area of the neck...am I just being paranoid and ignorant about this, or is a glove mold a possible recipe for disaster? Any second (or third, fourth...) opinion(s) would be greatly appreciated.

Kind regards,

AJS

[mantrid]

I can see no problem of using a glove mould for this. The slit at the back would only have to go half way up the hair bun too. I think you under estimate the flexibility of the silicon. Also you say you will use a mother mould this means the silicone can vbe thinner and even more flexible.
Beautiful work by the way

[ajoysisk]

Thank you kindly, mantrid! Your words put me at ease.

[Andrew Werby]

I agree; the glove mold should work fine. Build up the area where you're going to cut it, so it's about half an inch thick or more, and use a zig-zag cut that will key the sides together. One thing you need to deal with, though, is air getting stuck in areas that will be pointing up when the mold is being filled, like the lobes of the ears and some hair details. You don't say what you're casting in this mold, but it will take some strategic rotation of the mold as it's being filled to get a good casting without voids.

Also, test that rubber on something made of the same material with the same coating on it, to make sure whatever it is doesn't inhibit the rubber from setting - platinum cure silicone is very particular that way...

Andrew Werby

[ajoysisk]

Thank you for the solid advice, Andrew. I am casting in Hydrocal as well as cold casting bronze...I will make sure that I am able to get a good cast in the plaster before even considering moving ahead with the resin. Wish me luck with the strategic rotations!

[Mack]

I guess the advice re the glove mold is correct. I have never done one though, always gone to a two piece mold. The head is great looking by the way. If I were molding it I would run the parting line up the back of the neck over the hair, a ways down the forehead and then to the temple down the cheek and back to the chin and down the neck avoiding all the detail of the eye, nose, mouth etc. I also would use one of the quick setting plastics as the mother mold rather than the heavy hydrocal. You can thicken it and brush it over the Plat-Sil and only need to build it up to a quqrter inch to get a strong outer shell. (never used Plat-Sil so don't know if a mold release is necessary, probably is.)
Nice work...good luck.

[mantrid]

Originally Posted by Mack

If I were molding it I would run the parting line up the back of the neck over the hair, a ways down the forehead and then to the temple down the cheek and back to the chin and down the neck avoiding all the detail of the eye, nose, mouth etc.

Completely unnecessary. Just a slit from the back of the neck to half way up the hair bun thing, and it will just pull off the front, bit like a glove Avoiding any parting line on the face and most of the hair altogether.

[ajoysisk]

Mack: Thank you for the new idea for a mother mold. I will have to try that sometime. All: Success! I didn't even make a cut in the silicone...the entire thing rolls off of the portrait. Thank you, again.