Measuring radius

[moro]

How do you guys measure the radius of your fretboard / bridge? Stewmac has a bunch of cool metal radius gauges but they're a little expensive for someone like me who is only going to use them once.

They're not outrageous, so I'll get them if there aren't any alternatives, but I was wondering if could use something I might have lying around.

Thanks.

[ryanb]

You could always make your own. Get a grade-school compass and draw out the radius on some suitable material you have laying around, then cut it out. Not as accurate, but close enough for a quick check. If you have (or are considering buying) Dan Erlewine's book, there are plastic pop-out gauges in the back.