Changing Tunings and Damaging Trems

May 8, 2012
Hey guys,

I have a guitar with a floating trem that I keep in standard tuning. I've heard that the bridge is supposed to be tilting slightly forward when setting it up properly, so that's how I've always had it. If I wanted to change to half a step down tuning (with 10's, this causes the bridge to sit pretty much parallel to the body), is this damaging to any parts of the trem? How much does this throw intonation off?

Also, what actions specifically cause damage to the knife edge?

The trem should be sitting parallel to the body, so you're actually spot on with the strings you have on it.

Having the trem sitting slightly tilted forward or back doesn't damage the trem, but it will throw the intonation off as you're very slightly increasing or decreasing the effective scale length. Visualise a string which is intonated correctly, the frets are spaced at the correct intervals, the the string is the right length. Imagine slightly lengthening or shortening that string. This will throw off (very slightly) the notes on each of those frets.

What ruins the knife edge? Adjusting the 6 trem screws (the ones that go into the body) when there is string/spring tension on the bridge. These are set at factory and don't need to be adjusted. They should only be touched if you're removing/replacing the bridge, and if you're not confident in doing this, take the guitar to a luthier that knows PRSes.

Here's some more info
I've always set floating trems to be parallel with the body.

What damages/wears the knife edge is using the bar. You have two hard surfaces rubbing together every time you move it, so they eventually wear out.