Safe tolerances from youtube
Though it's aimed at total laypeople it's still enjoyable at the hobbyist level (at least where I currently am at )
It's also a good lesson on why tolerances count and why not to choose birth dates.
(Squelchtone if you read this: I can't post it on the open section of lp101, can I? Since it's safes and combination it would need to be posted in the advanced. I wasn't sure so if I don't get the green light I'll just post it in the closed section )
=== WARNING DANGER OF TYPOS!===
Arfspeak: calnin cladycomes: you allow her key in themodning
Equals in plain English: cleaning lady comes: you allow her key in the morning