Re: Functional Gages give different results
Threads are very forgiving for the most part.
The design of threads allows for assembly regardless of many expected errors in the manufacturing process.
The design of the thread gages allow for torque variation between operators and calibration technicians.
IMHO: If a minor deviation on a product thread causes a great “Risk” of failure, then the product design is faulty; pushed too close to the operating limits of the thread.
Threads are not intended to be inspected by micorscope.
… Even the amount of torque the calibration tech uses versus the inspectors can create a variation in passing or failing a part. It is a very dicey measurement technique, especially for tight tolerances. For that, you may have to section the part and measure the threads - or use a tri-roll thread gage - to get variable data.
I've seen these situations arise as completely theoretical exercises, and threads (male or female) that would work perfectly well in the application get rejected because of questionable gaging.
... One would need to look at this aspect and assess the "Risk" involved in accepting defective threads vs rejecting acceptable threads.
The design of threads allows for assembly regardless of many expected errors in the manufacturing process.
The design of the thread gages allow for torque variation between operators and calibration technicians.
IMHO: If a minor deviation on a product thread causes a great “Risk” of failure, then the product design is faulty; pushed too close to the operating limits of the thread.
Threads are not intended to be inspected by micorscope.