Relevant technique at timestamp. Basically, you mark out at least two different reference angles plus a scrap block/protractor and eyeball it. You'll get withing a handful of degrees, which is close enough.
Thanks! I'll give this a watch, but the description sounds right.
I had one before, for about 2 years. I think I used it 4 times for something my cordless could have done. But I wasn't really "making" stuff back then, so we'll see how many times I find myself wanting one nowadays. So far, this is #1You only think that because you don't have one.