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It seems that their are potential issues with top stress cracking from neck on each side of the neck towards the soundhole...at least with the older OM models. Is there an xtra brace option to help beef this area up or compensate to help minimize this direct...but seemingly age related stress cracking to the top? I Currently have the Payne plans and working on all my bracing right now....and have a bolt on neck to attach. The Payne OM plans show a 2 1/8 width neck block and mine current block is 2 3/4. Should I leave this extra width to help support each side of the fingerboard beneath the top? ....or do I need to do something else between the block and the Soundhole other than what's on the plans. Maybe this potential stress issue is already factored in with the Payne drawings....I have nothing to compare it too.

Kent Bailey

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Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

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Kent it is IMHO. The Popsicle brace next in line below the neck block is a traditional method to deal with the stress riser created by gluing the fretboard extension to the top. The brace is shown on Michael's excellent plans.

Another thing that you can do that is yet another great idea from the House of Mario is to only glue the fretboard extension down with a small puddle of Elmers white glue, you know the old school glue that kids can eat and make, well you know.... The idea is that if the fretboard extension is not glued at the edges the stress riser is less of a stress riser.

Others use A frame bracing and there are a number of other methods that I am aware of as well. Some folks make their living removing the Popsickle brace to "hot rod" the guitar and open up the top more.

As a guy who at times works in a busy college town repair shop we see plenty of guitars with the cracks beside the fretboard that you are describing. The Popsickle brace is no guarantee that it won't happen if the guitar is permitted to dry out or other stress occurs. But IMHO and that of other folks that I know it helps avoid the cracks.

On my current plans I have a flanged neck block that extends 2 7/8" into the body. If you do not use a flanged neck block the you may want to use a Upper transverse graft brace between the upper transverse brace and the neck block. Commonly called the popsicle brace because of its low an wide shape typically ¾” to 1” wide and ¼’ or less thick. Also “A” braces like used around the sound hole from the upper transverse brace to the neck block will help eliminate this issue.

No brace can stop a crack.
A crack is caused by wood shrinkage & not much else!

Abuse is the only other reason .

Make sure your woods are dry & that you assemble your guitars in a low 40% or so enviroment.
Use epoxy on the f.board joint so to not add moisture to the top ,f.b, & neck.

I've never had this problem with over 300 guitars .
Mike

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Mike Collins

The reason for these cracks is the difference of shrinkage rates between the sound board and the fingerboard. Mike is correct that no brace will stop a crack but the popcicle brace will help to prevent the neck block from caving into the sound hole,that makes a mess. Hesh has pointed out the correct way to deal with it,light soft glue on the fingerboard extension,but I would install a popcicle brace as insurance.
Tom

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A person who has never made a mistake has never made anything!!!

The Popsicle brace will help control the cracking from shear stress of the fretboard extension . If your cracks are issues from Humidity , there isn't much that you can do brace ways to stop that . In A frames there is a shear controllers that ties this area up and helps to control the shear stresses .
There are some options out there. I use a smaller version of a Popsicle similar to what martin uses but not as long. Mine are about 4 1/2 inches long . This should help control the shear along the fret board.

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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

My popcicle brace is about the same size as John's. When I first started building I built without this brace,please don't ask me why I added the brace in all subsequent builds.

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A person who has never made a mistake has never made anything!!!

Does someone have a visual of a proposed neck supporting/top Popsicle brace of some kind for this?
I'm a visual kind of guy.
Thanks for all the replies.
Kent

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Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

http://www.kabart.com