How to make a mold from a human leg?

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#1

Hello:

Well, since the success of my shin guards, I which I want to thank all of your help, now I want to take one step further.

I want to do a custom size sin guard, there are some places that offers this through the web, but not here in my country yet. my Schedule in order to build the mold is:

1 apply body oil on the skin of the leg
2 apply plaster bandage on the skin of the leg
3 wait to dry
4 take the mold from the leg
5 apply a thin coat of tooling gelcoat
6 polish

I think is just a basic mold process, it is not rocket science, but I dont want to skip something.

Any sugestion for this is greatly welcome!

Thanks.

Antonio

#2

I don’t know much about taking moulds of actual body parts, but I’ve seen how a face mould is taken.
Apply a silicone mix, let it cure and reinforce it with plaster bandages. Reason for this is that its safe on the skin takes only 10 minutes and the silicone will allow for muscle movements in the leg. Remove the mould and take a casting off it. Now use the casting as a plug to make a normal GRP mould.

#3

Agreed, nearly every time I’ve seen someone take a mold of a body part it’s with silicone.

BUT the plaster method should work, because when I interned at a orthotics and prosthetics place a few summers ago they did use straight plaster to take a mold of amputated stumps (and just for the record, stump is a medically acceptable term :slight_smile: ) this might have been because they wanted more precision, and eventually also made a silicone insert from that plaster casting so it might have been because they couldn’t make a silicone positive out of a silicone mold.

#4

Yeah you can use plaster no problem. In college we did plaster moulds of our faces. I think we just put vaseline on our face first, then people put on the plaster bandages.

Probably the only thing I would add with the plaster is to add some fibreglass reinforcement if possible (once the plaster is dry… if the glass & resin is compatible). Reason being that I would just prefer some extra reinforcement. Unless you make a very thick plaster mould… I’m just thinking of all the pulling and prying forces when you are demoulding a part from it.

If you have a look around YouTube I’m sure you’ll get some ideas. There’s some really cool products out there in the special effects/body casting industry.

#5

Another option is to use alginate. This is a sort of tooling rubber, made from algae. It is a powder, and is mixed with water. The resulting paste can be put on skin. After 3 minutes or so it is cured enough to remove. I remember we had 3 and 10 minute versions.

#6

How to make a mold from a human leg?

Okay, first you’ve got to hollow out the leg and then… :smiley:

You could check out http://sculpture.net/community/ . They seem to have a lot of pro artists and advanced amateurs on that board. I’m sure someone there could give you good advice.

#7

Maybe whe you figure it out you can get a job like this

#8

Is that CSM stuck directly on the ladies torso? Itchy! :laugh:

#9

You can do plaster and Alginate, but they shrink slightly. Alginate shrinks slowly, so as long as you pull a plaster/resin/silicone master off the mold quickly, you might run into problems.
Do not use silicone!!! Not good for the human body, and takes a long time to set up.

Also, look at pregnant belly molding kits. They are plaster covered gauze strips. You wet, and apply to a jelly covered skin. Did that for a body mold of my wife to make a dress form. You can seal with primer and paint, and release. You can also make it thick, or back it up with more plaster/fabric to make it thick and strong.

#10

You can get skin safe silicone with a 5 minute cure. Smooth-On make one, I think it’s called body double.

#11

I am concerned about silicone & alignate, they look soft, then maybe it would not get an accurate copy from there. At this moment I am thinking about give a try with plaster.