How do you cut a thread form on a core for a mold?

[jryles]

I am working on a mold for a rubber part. We have a specified thread form at one end of the mold ID core. We initially thought threads no problem just turn them up on the cnc lathe, but once we started to it then we discovered that every thing is backwards and the tooling methods are to us non-existent. This is a rubber part so it will pull off. My problem is how to cut the thread and have the start and finish of the thread feather in and out. The only way at this point is to EDM burn as far as we can see. This was to be a quick and cheap mold. Any thoughts or ideas please let me know. Keep in mind this is a mold for silicone rubber. The material is very flexible but will fill the smallest gap with rubber and hydraulically spread the gap over time.

 

[Like2Strike]

jryles,

You need the services of a thread grinder.

I used to use the services of
B & R Grinding
Franklin Park, IL

These guys are very good!!

Live Aloha

Frank M.
Tradewind Resources

http://www.tr-usa.com