#1
I got a mim stratocaster a month ago, and I never changed the tunings and kept it standard. Well i decided to tune to open g, and when I detuned the 1st and 5th and 6th strings, the 4th,3rd and 2nd string went too sharp. then when I was in tune to open g and I tune those 3 strings to standard, the other 3 string went too flat. This doesnt happen with my other guitar, which is a yamaha strat copy, well not at least to the degree that my strat is doing.
#2
When you don't tune all the strings uniformly, sometimes the ones you don't tune/tune differently can be affected, and so their pitch can change even though you haven't detuned them. It's probably because there are very slight variations in the wood due to changing string tensions in certain places, cause slight variations in the wood in other areas, thus affecting the tension of other strings. Maybe.
#3
You should tighten the springs in the trem cavity to increase tuning stability. Also, lube the nut slots with graphite. And lastly, strings kind of get "used" to what ever tuning you use so you'll have to retune a couple times in order for the strings to settle in to the new tuning.


Don't forget to set your intonation for new tunings either.
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#4
I saw the thread title and lol'd. It probably has to do witht the strings being "used to" being a in a different tuning, and trying to return to their "correct pitch"
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