On my first mold, I found a little scrap piece of alumnin to see if I could do it. I made a stinger bait,clamp 2 pieces metal together and drill 3/4 inch deep with about 3/16 bit,then use 1/16 or smaller bit for skinnie tail drill 2 inch deep. On the 3/16 bit for head can use 1/4 but I like to redip head to make 2 color bait and smoother head also.Then I went to metal shop and bought a 2 x 1/2 or 3/4 thick strip of metal. For flat tail I used a Dremel grinder with a cutting blade and only grind a little metal off of one side of mold the shape I wanted. This mold was harder to do than BGSS style which is real easy as long as you keep pulling bit out of alumnin before bit clog up. I had a drill press which which help. When I redip head I would ease bait into water than do one right after another. I hope I explain it ok.