It sounds more like you're having an issue with either the way you're picking and the tremolo or the strings causing the guitar to go out of tune. The Squiers don't have the best hardware, but they should still stay in tune. Here are some tips:
Stringing your guitar
After restringing your guitar, you should stretch the strings some to help them settle in. If the last time the guitar was strung was by a technician, that person may or may not have stretched the strings or might have done just a quick job of it so you might want to try this first. At the 12th fret, pull up on each string individually by grasping it with your fingers and pulling it away from the fret board. After you stretch one string, tune it back up to pitch before continuing to the next. I always start with the high strings as they are easier to break and you might be a little too rough with them if you start with the low strings which are more difficult to stretch.
Assuming that the tuners on your guitar have a hole through the side where you slip the string through (vintage style Fender tuners are a little different), I like to use an
x pattern for securing the strings on the peg head. Also, you want to use loop the string around the peg head only two or three times; any more than that is not needed and can cause the string to have the opposite effect and slip and stretch.
Tremolo bridges
Tremolos bridges are basically pivoting fulcrums. With a floating setup (where you can pull up on the bar to raise the pitch as well as push down to lower it; typical setup), the center point is balanced between the tension of the strings and the springs in the back of the guitar. When you push down on the bar or the string tension is decreased and the spring tension increased, this causes the bridge to pivot forward toward the strings. The important note is about string tension: if you pick particularly heavy (as I tend to do), you can cause the string to pull the tremolo bridge forward making the strings go flat for a moment or two until the string goes back towards normal tension. There are several solutions:
- Play more lightly.
- Increase the tension on the springs by adding more of them. This will make the tremolo stiffer and more difficult to use but will provide more resistance to accomodate heavy picking. Adding more springs will cause the bridge to go back toward the body; if you want the bridge to be floating as well as it get it back closer to where it's properly intonated, you'll need to loosen the screws that fasten the
spring claw to the body of the guitar. You'll most likely also need to adjust your intonation afterwards using the screws on the string saddles.
- Set your tremolo to be non-floating where you can press only down to lower the pitch. This is what I decided to do as I don't use tremolos that much to begin with and, personally, I find floating tremolos to be a pain because of the way I pick and just for ease of tuning. Besides, I bend up using my fretting fingers. YMMV depending on your style. You tighten the spring claw screws to bring the bridge back so that it's against the top of the guitar; you'll need to find a spot where your picking and strumming isn't causing the bridge to dip forward yet the bar isn't too stiff for your taste. You'll definitely need retune all of the strings and adjust intonation afterwards. A side benefit of this method is that you'll get a little more sustain out of your guitar as there is more mass from the bridge making contact with the body; it's not a huge difference, but it is noticable.
Those last two suggestions are a bit time consuming and can be frustrating to deal with and might best be accomplished by a technician unless you're willing to do a little trial-by-fire and still take a chance on having to take the guitar in to a technician if it becomes a nightmare. Setting up guitars isn't rocket science (they're actually pretty simple contraptions) but, personally, there are some adjustments I'm willing to make and some I'd just rather pay someone else to deal with (necks on vintage style Fender guitars immediately comes to mind). It's good to learn how to maintain your instruments but, if it starts taking away from the time you have to play and your enjoyment or just becomes totally frustrating, then it's time to talk to a tech. That Dan Erlewine book is excellent but, even with good instructions, there are some things I just won't touch; you'll need to decide for yourself what you're willing to take on.
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Devil's Advocate.·´¯`·..·»
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