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Units, metric vs. imperial

To begin with, I have to say that I am from Germany. I know a lot of people in the US love their imperial units, like slugs and pounds, ounces and feet and yards. Now, at Pololu I find a wild mix of styles. Lots of oz-in when it comes to motor and servo torque, in many cases accompagnied by the kind-of-metric (but not really SI either) kg-cm. I like this one especially:

because the diameter and the length of the shaft are given in mm and inches!
In some cases, like a 1/4" diameter shaft, it makes sense to use inches, but for all other occasions, wouldn’t it make life a lot easier if everything was just given in correct SI units?


Thank you for your feedback, and sorry for the delayed response. Most of us would also prefer it if everything was always done in metric units.

For the 37D motor you pointed out, I am not sure why the shaft length was originally listed in inches, and we have changed it since millimeters do seem to make more sense there. As for the rest of the site, there are probably many instances where we would change the units if we redid the product page today. However, combing through the entire site now would be a huge undertaking, and our time is probably better spent adding new products or new documentation instead of changing specifications that are correct, but could be more conveniently presented.

On that front, we have put a lot of thought into details like units in our dimension diagrams, and those are the best source of mechanical information for products that have them. We are also currently working on publishing more electrical data for our motors and are likewise paying close attention there to details like which units are presented, so we will be sure to take your feedback into account.