Ok, we all know that when bonding plastic together there are many methods to do so. There is bondo, epoxy, polyfiller, and then there is ABS cement. I prefer ABS cement because it completely bonds the peices of plastic together, forming one solid piece. Here is how you make it.
Supplies you need:
A case from anything made out of ABS plastic.
a glass jar with matching lid. Any glass jar will do as long as you plan to never use the jar to hold food again.
lacquer thinner or acetone. Your chioce, really. acetone is in the thinner so it doesn't really matter which you use.
Cut up your ABS case into small pieces. Make sure they are around an inch wide and long or smaller. Too big of plastic will take too long to melt. Have too much plastic pieces left over? Don't throw them out. Just get an old butter container or something and store the bits until you need them.
Fill the jar about two thirds of they way up with plastic.
Now pour in your thinner or acetone into the jar until it is halfway filled. too much will make the ABS cement runny and too little will make it extremely thick. If you are unsure of how much to add then just experiment a little.
close the jar and wait. A long time. About two days or so. After those days are up the plastic will be completely melted into thick goo. It is now ready to be used for frankencasing.