Yet another pair that has been unfinished for a long time. This is my first experiment for using plaster casting to make soles for Monster High doll shoes.
First I made the master in two parts using balsa wood. I carved the arch before gluing the parts together. Then I carved the final shape after gluing.
As balsa is very soft, it is best to carve a close approximate first, then continue by sanding, then apply several coats of acrylic paint, and finally finish the surface by sanding. As the surface of the casting will remain hidden under leather, fabric or whatever material you're going to use to cover the soles, the surface doesn't need to be very smooth. Just make sure there are no big bumps or holes.
Here the master is covered by latex used for making the mould. At this point, the latex is already dry and there is talcum powder to make sure the surfaces won't stick together as the mould and master are separated.
I made two moulds, so I could make a pair of soles at the same time. Here the plaster has been poured into the moulds, which are supported by some pieces of cork. As you can see, the mould on the right has too much plaster in it, but that doesn't matter as long as you remove the casting as soon as the plaster is hard enough to do so and carve the extra plaster away using a sharp hobby knife.
Here are the dry castings and pieces of leather to cover them. PVA glue works best for this purpose.
When using leather, you can spread glue also on the sides of the soles as it won't seep through. If you glue the sides, there is no need to glue flaps to the bottom of the soles, but you can just cut the excess leather and the cut edges will be covered by the leather piece glued to the bottom of the sole. The leftover pieces glued to the top of the soles here ensure that the insoles will stay even when glued in place.
If you use fabric, use glue only on the ends of the piece (it is best to place the seam to the inner side of the sole, to the place where the arch ends and flat part starts, as it won't be so noticeable there) and on the flaps to be glued on top and bottom of the sole.
Here are the finished shoes. The insoles consist of two layers of cardboard and the leather insoles. When gluing the straps in place, it is very important to make sure they are loose enough, so the shoes will go to the doll's feet. Unlike cardboard and leather construction, the plaster casting soles won't give in at all and the placement and length of straps needs to be considered carefully. The bottoms of the soles are covered with pieces of leather.
I'm not very happy with this first try as I realized that black leather isn't very good material for something like this. These should be much more extravagant, something colorful or glitzy would have been better. I've got another pair of plaster casting soles waiting, so I'll need to find something better for them.