Why does nobody mention that 1/2-13 is not the same as M12

I was threading a 12mm hole last week and grabbed a 1/2-13 bolt just to check depth, and it threaded in about 3 turns before it got tight. Looked it up and 1/2 inch is 12.7mm, so it's close enough to fool you at a glance but the pitch is totally different. A guy on a machinist forum told me he's seen guys cross thread M12 and 1/2 hardware on the same job and not catch it until final assembly. How do you all keep metric and imperial hardware from getting mixed up on the bench?

0 comments

Log in to join the discussion

Log In

0 Comments

No comments yet

Be the first to share your thoughts on this discussion.