Well Captain Fred here is a quick and dirty how I make a mold for a TJET. First find a diecats body that has the wheelbase you want or an existing TJET body you want to reproduce.
There are two ways for the 1st step. Some people grind out and mount the diecast to a tJET first and make the inside mold ( also called male mold) and some people make the outside mold (also called female mold) first. I make the outside mold first as I want to make the resin body as thin as I can.
So you have the trusty diecast car in your hand. Look at it close if the bumpers are molded to the body great if they are sepaerate pieces great but if they are molded into the bottom of the car you have to do the 1st step a little different. If the bumbeers are molded to the body or seperate pieces then drill the two rivets out on the bottom of the car and remove everything except the glass and if sepaerate the bumpers. If the bumpers are molded into the bottom of the car take your trusty dremel tool and cutting disk and cut through the bottom of the diecast just behind the fron rivet and infront of the rear rivet. Then remove everything except the glass.
Now fill all of the inside of the diecast with Kleen Klay, it should be squishing out the side windows, and wheel wells and at least 1/4 inch below the bottom of the body. Now clean up the side windows making sure they are indented (clay is pushed in from the side of car), indent the wheel wells and clean up the edges where the clas meets the front and rear bumpers and side of car.
Now polish up the car and remove all fingerprints etc.
I then place the car on a flat piece of plastic. I use old CD cases, Ziplock top that I have cut etc, just a thin piece of plastic. I then take a small mold box with the bottom cut out of it over the car and tape the edges of the box where they meet the flat plastic.
I ten mix up enough silicone to fill the box which is normally one bathroom cup filled 3/4 with part A and one bathroom cup filled 3/4 with Part B and mix. I use Smooth-on's OOMA 25.
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