Guitar goes sharp (tuning)?

I have a strat plus from the mid/late eighties. it has locking tuners and an early floyd rose tremelo. it has be in it's case for two weeks.
yesterday i took it out. put it to the tuner and it was sharp.

never noticed before. so now there are two guitars that do that.

on the other hand. when I tune without a tuner, usuing my ear and just tuning I tend to tune sharp. after a series of tuning that way I can only imagine it gets sharper. so when I put it in the case for awhile I shouldnt be surprised it is sharp.

so there is that scenerio to consider.

When I tune by ear, I have to tune sharp (it sounds sharp to me) to be on. Guess that means I'm naturally flat. :D

Anyway, this isn't the case. I tune with a chromatic tuner (it's built into my xtl). Sequence goes something like: pick up guitar, tune, play, retune if needed, play some more, put down guitar. Yet, virtually every time I pick it up, it's sharp.

I'm not sure if this is related, but I think there's buzzing on the low E where there wasn't before...

Typically a guitar with a trem will go sharp after sitting or playing a little if the trem is not centered/flat with the body. In other words the trem base itself is not flush with the body. When it is forward a little the springs will tend to pull it back and that makes it sharp.

Now having said all that, this is only a possibility if ALL strings are going sharp.

I'm not sure if this is related, but I think there's buzzing on the low E where there wasn't before...
Possibly another sign the trem is leaning forward.

Yes, most times it is all of the strings which go sharp. The lower three tend to go sharp more often or first (depending on how long I let the guitar set).

Is this normal? How does one check for this condition (trem leaning forward). More importantly, how does one aleviate/prevent it?

I get the impression the springs are getting weak and not returning to their proper position until the guitar sets for awhile. When you tune and play for awhile the springs are held in a off floating position and don't get a chance to return completely. Then after it sets for awhile they eventually return causing the strings to go sharp. Is the bridge level with the body of the guitar?

Joe

As far as I can tell, the bridge does appear to be level. That is, the bottom plate of the bridge appears to be parallel to the strings and the face of the guitar. It is a new guitar, so I'm hoping the springs wouldn't be weak.

The buzzing was not present when I used a capo and lightly strummed the strings with my thumb. The capo was positioned on every fret from the first to the tenth. That leads me to believe that the buzzing is a result of my (poor) technique.

its probably just the weather!
As the strings get cold they contract and tighten.

Been thinking about this problem a lot. My best guess to date is the temperature of the bridge metal. I tend to tune every few minutes (after every song). I also tend to rest my hand on the bridge. The guitar warms up as I play, thus everything expands. The strings are tightened to compensate. When the guitar cools down, everything contracts. Hence, the guitar goes sharp.