For the amount of time i've been playing, you'd think i could do it right by now. I just went to change a string on my gretsch g5120, the low E string, and as I was winding it up, i noticed that it was tuned way too high already, even after barely two turns. the string feels too loose, but it is tuned higher than my A string. Can anyone tell me what I did wrong?
Rockabilly rules, Okay?
you didnt leave enough of the string between the tuner and the bridge. after you feed the string through the tuner, grab it down by the pickup and pull it about to the volume knob and you should have enough slack to give you a few winds. as you get to the smaller strings you will need less slack unless you want a shitload of winds for the plain strings.

dont be embarassed man. i still cant get the exact same number of winds on each string whenever i do some restringing.

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I know how you feel. I had this happen to me too. You need to leave some extra string. Hold the string while you tighten. This should ensure that the string lowers itself down properly as you tighten.