mold making
I have copied lures in heat vulcanized silicone, and plaster of paris and am about to try an alum one. I can see how machining an aluminum do-it mold would be difficult because you have to design your program for each half based on your measurments of hinge location. It would be much easier to make your own mold without a hing. Im doing 2 half located with dowel pins. I also had a mold making machinist make me a 16 cavity mold out of alum he alon charged me $60:D but broke a bit and stated any other mold would be much more expensive.
The best way would be to cad a program for a mold. I would really recomend taking a CNC milling class at a local community college and making it yourself. It has probably cost me close to $100 just in mill & drill bits just for all shapes, on a cnc your would probably only need maybe 3 bits at most. 6/1000 is really bad. When you make a dowel pin mold your slop runs 2/1000 and your machining should not me out by more than 1/1000. They will help you and you will learn alot you could probably start desiging and making a mold after about 3-4 classes. I am doing mine on a manual mill, and do see some difficulties arising. I also recall someone making silicone mold for people in ny and only charging $30. Molds take alot of time and hours go by fast, a good price would be $150 for any simple design. Once you make a cnc program you could turn out a mold in probably 5 minutes at most. Im making mine all in one piece then cutting in half and everything sould line up, at worst the inside will all line up and the outside will not be flush and then you just mill it flush. Good luck
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