Official Luthiers Forum!

Is it better to have the x brace extend through the rim or to leave it short of the kerfing?

There's no "better" when it comes to that issue. It's a builder's preference, depending on what impact they feel inletting/not inletting has on tone.

In addition to the tone question, and both methods make fine sounding guitars, past conversations on this issue also mentioned that tucking the X-brace gives some security if the instrument is bumped and helps to prevent the brace end from popping loose from the soundboard. Conversely, if you feather the brace end to nothing before the lining, there is little mass at the end to encourage the brace from being loosened and the brace has some flexibility, which also helps keep it from coming loose. My last one had feathered braces (none tucked below the soundhole) and I like the result.

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

Given that the torque on the bridge is pushing the braces above it downward, and trying to peel them loose from the top, I would strongly advocate inletting the braces above the bridge at least.

I inlet all back braces . I never go through the sides just into the kerfing. On the top I will inlet the main X's and the truss rod braces. All others I fade to the top just short of the kerfing.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it