Today we are making a reusable mould to create latex wounds.
I need a latex wound that looks like a stitched medical incision. By making a reusable mould for it, I will be able to make several versions (such as infected/healing well/open wound/torn stitches) with the same mould.
You will need:
Plasticine (Use non-drying plasticine)
Plaster of Paris
Liquid Latex (I used Trylon Liquid Latex Rubber)
A sealable container (to permanently hold your mould)
Step 1: Mould the Plasticine
Using the lid of your pot, mould the plasticine into the shape you would like your final latex mould to take. I would recommend making the mould (and finished latex piece) wider than you expect, as you can trim the edges to size later.
Mould firmly against the lid, it will stick on well, assuming your design is relatively flat.
Step 2: Mix Your Plaster of Paris
Follow the instructions on the packet. Make sure you are making enough to fully cover your plasticine.
Mix carefully to avoid lumps, and be aware that the Plaster of Paris will start to set quickly
Step 3: Ready to Make Our Mark
Put the lid firmly onto the tub of plaster and invert. You may need to tap the sides to encourage the Plaster of Paris to fully move to cover the plasticine. Gently dropping it from a few centimetres onto a flat surface can help release any bubbles of air - but make sure that it is tightly shut first or you will get plaster on your shoes!
Step 4: Whups! Plaster Started to Set!
If you spend too long taking photos for instructables, you may find the plaster has started to set and cracks when you 'encourage' it to move down into the lid.... don't worry! Its just aesthetic damage on the bottom of our mould, and a bit of extra plaster can neaten that up.
Step 5: Leave to Set for an Hour
After an hour, gently remove the lid and peel away the plasticine. You will (probably) be able to reuse the plasticine for future mould making, so wrap it in clingfilm and store it carefully.
Leave the mould to fully harden overnight before trying to scrape out any harder to get bits of plasticine.
Step 6: Neatening Up
Use fine sandpaper to neaten up and smooth out your mould where needed. I like to use a nail file to get into those hard to reach places.
Step 7: Latexing
Tip the liquid latex over the mould, then tip the excess back into the pot. (Saving those pennies!)
Leave to dry. If you have a hairdryer with a cool setting, this can significantly speed up this step.
When dry, repeat the process until the mould is of the correct thickness. (I would use at least 4 layers to make it strong enough)
Step 8: Lots of Layers Later...
Leave to completely harden overnight (possibly longer if making a thick prosthetic)
Cover in talc to prevent it sticking to itself and remove from the mould.
Step 9: Neatening Your Latex Piece
Talc all over and trim the edges so it will blend more easily into the skin.
Step 10: Adding the Details
Paint your wound. To avoid the paint cracking or peeling away, mix acrylic paint with liquid latex 50/50 and paint your wound with that. Use dark reds in the base of the wound and work up, to create realistic depth and shading. Let it dry completely between colours/layers. Now you are ready to stitch the two flaps together. (Paint then Stitch, or you are going to have a bad time!)
Add fake blood if you are looking for a very fresh/broken wound, or pus if aiming for infected. These should be able to be gently washed off between scenarios.
Step 11: Affix to Your Manikin
Here I have simply taped my piece onto the manikin, and added a dressing, but you can also attach with PVA glue or more liquid latex too.
Step 12: Finished Piece
Added a bit more blood for a fresher look.
Best thing about using this latex piece, is none of the blood (should) get on the manikin, making clean up very quick - all ready for the next scenario.