It's funny, I go to CISCO (hydraulic shop) on a Saturday, and the guy behind the counter won't touch them unless I want them to turn out ugly.
He says to come back Monday for the guy with 30 years experience, as if it's some sort of an art
I believe it though, since I only ended up there after botching a few attempts and getting scared that I'd run out of line!
I was using the grinder method.