Most tuning problems are with a vintage trem are at the nut. Make sure your nut sluts are as close to perfect as possible (I use a bone nut. Use virtually no string wraps. This is controversial and doesn't work with some guitars. Go read about properly installing your bridge so that the back plate doesn't bind (screw it down to the body then back a turn--there is more to it than this but this is the 'proper method' I speak of). The better your bridge is, the better off you will be. It needs to be a nice gliding and frictionless system where the strings don't bind up anywhere, and the bridge pivots on the body screws ok. I think the most important factor is how you put on your strings. Stretch them and add tension while you are winding them, stuff like that (we all have our own systems, their are many ways to change your strings that will work). I also use graphite powder on the nut and the string trees (the string trees are almost as bad as the nut for binding up your strings).
I do all this stuff more or less and my vintage bridge is pretty stable. It stays in tune quite well and I have it set to float so I can pull up at least a whole step. It stays in tune great, for a vintage setup. IT is still unpredictable at times. Sometimes I am amazed at its stability, sometimes it slowly goes out of tune but only when I get aggressive with it (but thats what I want it for sometimes).
If you use locking tuners and a graphite nut or a roller nut your stability will be greater. These innovations move you away from the vintage strat sound though so if that is what you are after using this hardware may not be your thing.
I am always looking for better ways to improve upon keeping a vintage bridge stable and in tune. It will never be perfect but you can get it close.
Putting dowels underneath the block in the string holes binds the strings in place. So when you slacken the strings they do not move up and down and reseat themselves in a new position, thus changing your tuning. I never thought of that or seen it done; but hey its not a bad idea. I believe that you say it works for you. It makes perfect since when you think about it. All that string tension someone mentioned above goes to nil when you press down on the bar and the string (ball ends) may slide out of position. THe better your bridge, the more likely the strings will seat themselves the same way (or not move at all) but I can easily see where your strings moving around in your block (the ball ends) could cause tuning problems. If so, then using the dowels would work great. Thanks for posting that tip.....
jms
www.peerlesstone.com
