Print Vision Question

[confab]

Has anyone here ever built a frame from a set of prints? Most of it is fairly obvious, but there's some oddities when it comes to how they measure degrees..

You'll see something like: 74°-4'

I get the 74 degrees.. What's the "-4 apostrophe" business about?

[confab]

An Example of what I'm talking about..

[Guest]

An Example of what I'm talking about..

[ATTACH=CONFIG]107957[/ATTACH]

i believe you will find it stands for 'minutes of degree'.............1 minute of arc = 0.0166667 of a degree.
like in a straight measurement that says 23.4 mm +or- 0.1mm

[confab]

Okay.. Makes sense.

Do we reckon that's a tolerance or an alternative measurement or something?

[JBinNC]

Okay.. Makes sense.

Do we reckon that's a tolerance or an alternative measurement or something?

74°-4' is the measurement. If there is a tolerance, it will be called out on the print somewhere.

There are 60 minutes in a degree of arc, and 60 seconds in a minute of arc.

That is a pretty precise measurement for something as relatively crude as a frame.

Jim

[confab]

Okay.. I can see that helping when you're talking about large distances. Like, cartography shit.

I agree, it seems like overkill for a foot or a foot and a half of a motorcycle frame, though. Nobody I know has the means to even measure a span that small, that fine?

It does make more sense now. I'd say it can be disregarded?

Thank you both for your help!