Here I will show to you how to make a fast, simple and cheap hot glue mold to reproduce small things.
Step 2: Preparing the thing
The small thing that you want to make a mold must support a temperature about 100 degree Celsius, that is the hot glue temperature.
I choose a half-dollar coin, but you could choose anything else.
First put the object above a smooth surface. Then spray a little oil on it and spread it evenly with a piece of cotton. Spread a bit around too.
Step 3: Making the mold
Wait for the hot glue heats well and slowly apply it above and around the object. Use your hand to push the glue rod inside the gun, to help the flux exit evenly. Try to avoid make bubbles (sometimes is difficult).
Step 4: Separating the object
Wait until the glue cools well and carefully peel the mold out of the object.
Now you have a fine plastic mold with all the details of the object.
Step 5: Reproducing the object
Spread a little oil inside the mold.
Now fill the mold with the material of your choice. I choose epoxy, but you could use another material, like clay or acrylic resin.