[JCharlton]

Welcome to North America, the only place where this is an issue.

I tried to move our team to metric due to the large number of M8's we had in stock for our Parker IPS extrusion. One system would reduce confusion I thought, M3, M4, M6, M8, but hasn't quite worked out that way, mostly because of COTS parts.

Instead, what I've tried to do, as much as possible, is buy black oxide fasteners for metric (mostly socket head cap screws) and stainless steel for imperial where required. Exceptions are shoulder bolts in imperial, and imperial shaft collars. That helps a little.

It is a teaching opportunity for students to learn the two systems, and that there are different standards. (NPT vs BPT anyone?) Our metric-trained Canuck kids have a hard time with fractions I'd say due to a lack of familiarity with inch measurements and all their halves and sixteenths.

There's no doubt the rest of the world is metric and due to global commerce the U.S. is seeing the advantage of adopting metric. It's ironic that the automobile industry has chiefly moved to metric fasteners given that imperial is also known as "SAE" (Society of Automobile Engineers).