Measurement Data

image link-topic-sf0.jpg

Here are various tables of possibly useful workshop information that I've gathered together.


Obviously, I don't know where the errors are; if I did I'd fix them. But I'm sure they're still there. I'd appreciate learning of any mistakes in these tables via an e-mail to "".

This is all public domain data, and the tables as I've worked them up here are public domain as well. It seems best, then, simply to place this present web page in the public domain (the linking and decorative images on it are also in the public domain). It is all free. Please do not abuse this; keep it free.

The canonical URL for these tables should be that of this present page:

This first chart is a survival guide to the mixed inch/metric shop. Basically, it starts with a listing of every inch system numbered, lettered, and fractional drill (with metric conversions). Given this, it expands out the fractions (as I can never remember the relative order of 64ths, 32nds, and the like). To this it adds the standard numbered and fractional inch threads (their numbering system is different from the drill numbering system) and metric threads. Finally, it adds those "preferred" inch sizes not already present, and "preferred" metric sizes as per US and UK standards. All of this takes nine pages. The "Explanations and Rationalizations" of this take an entire page, and are certainly not without controversy.

The second table gives all that is necessary to do the same using both US and UK preferred metric sizes and threads. All of the bazillion drill sizes become just decimal numbers, which don't need to be listed as such. It takes two pages.

The third table gives all that is necessary to do the same using only the US preferred metric sizes and only "coarse" metric threads. It takes a single page.

About the images

Select Resolution: 0 [other resolutions temporarily disabled due to lack of disk space]