mixed units

[LCHIEN]

A few years ago I bought a 3/8" forstner extension, probably from MLCS
A 5" one like the top one pictured here

Naturally I figured its in the USCS fractional inch units because the shaft is exactly 3/8" and made to extend a 3/8" shaft.
So I spend 5 minutes trying three different SAE allen wrench sets trying to find one that fits the set screws.
Well after going through three sets I finally try the metric set and lo and behold it is 3mm hex wrench that fits perfectly.

Why in the heck did they mix units? Probably foreign manufacture and they have lots of metric set screws.
But is it too much to expect that tools made for fractional inch users should use fractional inch fasteners?

I guess that's the new reality of an increasingly metric world where everything is imported.

[twistsol]

The opposing view is that it's bad enough that in a metric country you'd need a special tool to drill a non metric hole and to add insult to injury you'd need to buy another special tool to use your special tool. It's been nearly 50 years since the US Metrification act was passed. We should probably get on that sometime.

[Jim Frye]

I've run across this with things like faucets and some finish hardware. I have a small box of miscellaneous loose allen wrenches saved from different hardware installs. I just spend the time sorting through the box until I find the right wrench and then set it aside in the tool tote for the duration of the job at hand.