What it takes to design a disc?
Here is a sample of all the detailed dimensions that go into the designing of a disc.
Notice 13 or so different dimensions just for the wing shape.
This drawing is before shrink rates are added.
If you made a part from this specific drawing the discs would shrink to be undersized and not pdga legal, plus the stability would be quite different depending on the amount of shrinkage that is factored in.
A VERY important part of the process is to be able to judge the shrinkage; finished products look quite different from the tool. If you made a tool (mold) from a disc it would be a lot less stable in almost every instance).
Typically the nose will draw downward and the center of the flight plate will dome upward.
The amount will vary depending on what type of polymer or polymers are used and how the plastic is injected into the machine.
Variables for injection molding a golf disc that can all change the final shape include:
Temperature of polymer.
Temperature of mold
Speed of injection.
Pressure of injection
Clamp pressure on mold
Transfer of position for times, speeds and pressures.
Holding/cooling time in mold.
Color of disc.
Humidity or temperature in the plan affects Cooling outside of mold which can be having the discs placed right side up / upside down / individual or stacked.
Most shrinkage outside the mold takes place in the first 6 minutes, but the discs will continue to shrink for up to several hours.