Advice from seasoned mold makers


Active Hunter
I'm looking to make a silicone mold of a helmet. Wha is the best method?

SHould I make a 2-part mold, one of the front and one of the back? or should I make a one part mold? I'm just worried that if i try and take the mold off one it has cured the master will break.

Also, if I go with a 2-part, should I mount the master on an armature or should I just suspend it in a box by building up a clay bed?

Please help folks!

Thanks in advance

things to consider before going on:
what is the shape of the object (I'm assuming a Fett helmet?)
Does it have undercuts that require you to make a two part mold (i.e. it will break when you remove the casting)

As long as you can easitly clean up the mold line then you will have less headache demolding a two part but you also run the risk of it not lining up every time.

The way you suspend it can be up to you. The last thing you want is to pour rubber then your helmet moving due to the weight of the rubber. Just make it solid and you should be okay.
hope this helps - I'm sure others will piggyback on what I said.
From my limited experience a two piece mould can be tricky to line up, especially if the join runs through detailed areas which makes cleaning up time consuming and tricky. The best thing is probably a skin mould, which can be backed up by a two piece plaster or fibre glass jacket. If your're in the uk i would contact Alec Tiranti Ltd they can supply you with all the correct materials and they sell inexpensive booklets explaining all the processes ( i'm using their T 20 silicone which is very tear resistant, ideal for skin moulds) Cheers.....TF
all you need is registration holes

then your two piece mold will line up,

surround half the helmet with a divider, such as build up a soft clay/plasticene (sulfur free), etc. bed around it, and make indents in the clay so that you have divets, bumps, and little holes that the silicone will go into.

once it is cured you turn it upside down and do the other side, remove all that clay you put on it the first time and once you have cleaned all of it off the other side of the helmet you will see that the silicone you poured earlier has contours and is not flat, the next pouring of silicone will be your 2nd piece to this 2 part mold and will match up with these holes each time.

BUT REMEMBER to spray release agent first onto all parts of your master and the cured silicone from part 1 of the mold.

this stuff is self adhering, it will stick to already cured silicone if you do not use a release agent, if you ignore this step, your mold will be trapped.

also remember to lightly spray release agent everytime you want to mold something with thing layers at the edges of the 2 piece mold, in case anything were to close the seem. saves you a headache of destroyign your mold when demolding.

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