Slacking- tightening strings

[man dough nollij]

I threw this out there in another thread, but it didn't get too many bites... I've done a little setup work on the couple of mandos I have access here, and have encountered a problem. In order to move the bridge around, change its height, etc., I've taken most of the tension out of the strings. To get the intonation right, I might have to do it a couple of times. What I've discovered is that more often that not, a string (usually an E) will break when I tension it back up. I'm wondering if experienced luthiers/tuners just count on new strings when making adjustments like this? I have one sick mando with a sinking top, which I tried to cure by careful re-humidification with the strings slack. The strings could only tolerate one or maybe two cycles of tight/loose before... PING! Also, I suspect that tight/loose cycles lead to string-deadening. I don't have a lot of spare strings, and I'd rather not blow through a bunch of them. Suggestions?

[Michael Lewis]

The manner of how the strings are attached to the string post is very important here. The string must wrap smoothly around the string post and not cross over a previous wrap. It is also very important that the strings not be tensioned more that what it takes to achieve pitch. Over tightening of the strings does deteriorate the ability to produce a good balance of overtones. In short, the strings go dead when stretched too much.

[sunburst]

I'm always surprised when I can completely set up a mandolin without breaking at least one E-string. About 3 cycles of tight/loose/tight is all I can hope for.

In fact, after all these years I'm still surprised that the E-strings can be tightened all the way up to pitch without breaking!

[Bertram Henze]

What would I do to get intonation right on a limited stock of strings?

1 - with new strings, only tune up to a moderate sub-pitch well below target. If the bridge position is correct for an E string wound up to, say, C (12th fret test), it will also do for the E string up to pitch. Re-slackening from sub-pitch has less devastating effects than from pitch.

2 - after bridge position is ok for sub-pitch intonation on E and G strings, tune everything up to pitch and leave it at that; what can be done with the bridge is done.

3 - ignore any slight intonation issues (7th fret versus next open course) from here on in; after all, this is a tempered scale system, i.e. a lot of compromises that can drive you nuts if you let them.

4 - if changing strings, do it one at a time to keep the bridge in position.

5 - probably get back to this intonation research project later, when the music store comes back in sight.

Bertram