Strings and set-ups

[Deliberate1]

I recently had my Merrill OM18 setup by a local luthier who did a great job. He fabricated a new bone saddle which, along with other tweaks, brought the intonation into line. String height is comfortable as well.
I gave him a set of D"Addario XS 12-53's, which have been my go-to strings for a year or so.
So my question is to what extent a string gauge change would throw off the geometry, and, if so, in what way. Would moving one step up (13's) or down (11's) cause an issue. I suspect string height is a factor in answering this question, especially for the 11's. I believe, but cannot recall exactly that he set the 6th string at about 3/32" at the 12th fret. I would not call it a low setup, by any means.
Thanks.
David

[davidbeinct]

I suspect that a shorter scale length guitar would deal with going one step lighter more easily and a longer scale guitar would handle a change one up or down. I have gone lighter on a fairly short scale Alvarez with no problem (12s to 11s).

[Deliberate1]

Originally Posted by davidbeinct

I suspect that a shorter scale length guitar would deal with going one step lighter more easily and a longer scale guitar would handle a change one up or down. I have gone lighter on a fairly short scale Alvarez with no problem (12s to 11s).

Dave, that was my thought as well.
Cheers
David

[birdsong]

Well for the contrary POV - I took one of my short scale instruments down a gauge and this has caused some buzzing when I go above the 9th fret.

More than gauge is the string tension. Not all 11’s yield the same tension. Same for the others. You are better served to go online and get the various tensions for the gauge and brand of interest. These have been posted here before.

In general a longer scale can better accommodate going one up or down. But this will also depend on your current setup. If you’ve already dialed in some relief going up a gauge with a given brand that really bumps up the tension may yield action too high for your style.

[rick-slo]

Originally Posted by Deliberate1

I recently had my Merrill OM18 setup by a local luthier who did a great job. He fabricated a new bone saddle which, along with other tweaks, brought the intonation into line. String height is comfortable as well.
I gave him a set of D"Addario XS 12-53's, which have been my go-to strings for a year or so.
So my question is to what extent a string gauge change would throw off the geometry, and, if so, in what way. Would moving one step up (13's) or down (11's) cause an issue. I suspect string height is a factor in answering this question, especially for the 11's. I believe, but cannot recall exactly that he set the 6th string at about 3/32" at the 12th fret. I would not call it a low setup, by any means.
Thanks.
David

Gauge up to 13's or down to 11's not likely to cause a problem (and if so nothing a small truss rod tweak could no handle). Depending on how the nut slots were made (tapered) there might be a change in string height coming off the nut but probably very minimal and not usually an issue.

The 6th string at about 3/32" at the 12th fret is on the low side IMO.

[tadol]

Gauge change should only require a miniscule adjustment of the truss rod if all else is set up properly -