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Product specialty
Externally threaded parts
Our name is not decorative. MTI's roots are in developing and molding threads, and it remains the thing we are asked to do that other shops turn down.
Why molded threads go wrong
When it comes to externally threaded parts, it is crucial to achieve size and tolerance - and plastic does not cooperate. Every resin shrinks as it cools, and it does not shrink uniformly along a helix. A thread cut to nominal in the steel comes out of the press undersized, out of round, or pitched slightly wrong, and it will not mate with the fitting it was designed for.
Getting it right means knowing, before the steel is cut, exactly how much a given resin will move and in which direction. That is a knowledge problem, not an equipment problem, which is why it is the specialty most often subcontracted away.
Threaded mold cavities
Our experience also extends to the specialized technique of cutting threads into molds for threaded mold cavities. Internal threads in a cavity have to be produced cleanly and then released without stripping the part, which is a combination of cavity work and ejection design most shops are not set up for.
We do both halves of the problem in-house on our CNC milling and EDM equipment, to a tooling tolerance of .0001 inch.
What we need from you
Send the thread specification and the mating part or standard it has to meet, along with the resin if it is already chosen. If the resin is still open, tell us the performance requirement instead - resin selection and thread accuracy are the same conversation, and choosing the material first sometimes makes the thread harder than it needed to be.
At a glance
- Tooling tolerance.0001 in
- External threadsYes
- Threaded cavitiesCut in-house
- Shrink compensationPer resin
- EquipmentCNC milling, EDM