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I am playing with a odd x brace idea. My thoughts are to glue cloth reinforcing at the rounded notches and glue in . History tells us that curved shapes are stronger than square cut outs . IE Bridges . So I have thought about trying this as an option . Most failure I have seen on the x stems from the notch . I am thinking about eliminating that squared corner situation . My braces are two piece glued braces as you might be able to tell with the one picture . Thoughts ?

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The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

If you're concerned about the x joint splitting, just cap it.

It would eliminate stress risers at the cost of all joint integrity. A glue soaked cloth will not help much.

My layman's interpretation says that whatever strength derived from the butt-glued sides of the x in contact with each other is lost. Whether the rounded shape if the complementary cutouts reduces a stress riser well enough to overcomes that loss, a structures engineer could enlighten us. But capping the top of the 'x' sure mitigates a whole bunch of weakness all by itself. Tapered splice, nice long gluing area?

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Peter Havriluk

An interesting experiment, and I honestly don’t know what the result might be. But I’d be prepared for some looseness just south of the soundhole.

So I’d stick a brace just below the soundhole, connecting the 2 parts of the x-brace.

I’d also expand the footprint of the bridge plate, to minimize the inclination to pull up.

That is the fundamental joint in the guitar. I’d be vary careful about weakening it without building in some compensation.

On the other hand, to quote Stephen King, “god hates a coward”.

Steve

I'd put a decent cap on that.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I’ve been capping mine lately with scrap pieces of BRW. Ideally I’d like to go taller to minimize the effect of the notch being the one of the weaker point of the brace.


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I don't really see a problem with traditional joint.
With the open part of the notches, a cap on one brace and the soundboard glued to the other gives quite a bit of reinforcement to the crossing point.
Can't remember seeing a failure reported on the OLF, or anywhere else for that matter.
Heavens, how many guitars have been made with just a cloth patch glued over a very sloppy or butt joint?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Always Cap my Joints , will on this one as well . That's not really the issue . I am experimenting with different idea . Thanks for the comment

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Thank you . I have a brace marked and planned for the point you referenced . Bridge plate , Good thought . I have some experience in engineering and design , so i'm not totally convinced its a weaker joint . In buildings / bridges etc: the curve or arch actually transfers the load more evenly outward toward the points of contact better than a square corner . I am actually wondering if I will get a bit "more" flexibility over the stiffer glued joint ? It is an experiment for sure .

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

I am not disagreeing on a traditional joint , I am curious to see how an alternative idea will work . Thousands if not millions I am sure . I have repaired several that split at the joint . I wish i had a way to deflection test this ..... May have to try to come up with an idea . Thanks for the comment

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Not Convinced that I am giving up joint integrity . I use standard joints as well , have on several guitars . Experimentation is the direction here . Thanks for the Comment

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

That's the crux -o- the matter . Arches tend to be stronger and deflect load outward better than square corners ... Capped .. Yes it will be Thanx for your comment

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

It will make for excellent marketing

You could try Howard's brick. http://howardguitars.blogspot.co.uk/2016/01/deflection-testing-of-acoustic-guitar.html

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

actually a glue soaked cloths does more than you may think don't take my word do an merriment and see what happens.

as a repair shop I have seen more failures from caps that cloth. Martin has been doing this since 1833 and there are few failures. Most of them can be traced to failure from outside stress.

Your curve will reduce a stress riser on one area and place it at another. The exposed brace is square on the top , that can be a point of a stress riser though your braces is wide enough it may or may not be a concern.

One of the most creative ideas was a slot that was cut into the X braces and a small 1/8 in insert that was 1/2 lapped opposite the X brace glued in. It looked pretty neat and was a different approach .

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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

From a structural engineering standpoint the issue is that you have cut a round notch halfway through the brace which reduces its strength significantly (about 75%). There is still a stress riser in the notch. In other words, if someone sits on the guitar the notch is where it will break.

The square notch in a traditional x-brace gets another brace tightly fitted and glued, completely filling the notch. As long as the joint remains sound there is little strength removed from the brace.

Jim, your design is a solution in search of a problem.

You could try Howard's brick. http://howardguitars.blogspot.co.uk/201 ... uitar.html


Thank you for the input . If someone sits on the guitar , square or arched somethin gonna give lolol I will do a deflection test on the braces . You may well be right. However curiosity is strong in this one . lolololol

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

John, I am surprised that you have seen several failures from Capped braces; it seemed pretty bullet-proof to me. Can you tell us more about the nature of these failures? If there is a hidden problem with that approach, I'd sure like to know. It may be that I am misreading your post and you mean that most of the failures (Including capped braces) can be traces back to outside stress. If not, how/where are you seeing the failures? Is the cap failing? The top notched brace? The bottom notched brace. . .

Of course, I'm not directing this only to John, let's hear from anyone who has seen a capped joint fail.

EDIT: Sorry Wud, I don't mean to hijack your thread/ it seamed pretty closely related. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Most of the ones I have seen either way Capped or Cloth the break tends to be at / close to the square corner of the notch . Thus the Idea to eliminate that stress point . Is this the answer ? Probably not. Figure its worth a test though. However John has probably much more experience in that area.

No prob Bryan .... All input welcome

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

I would suspect that many of the cap failures John sees would be due to inadequate glue surface area each side of the joint. Many caps I see are cut back dramatically with the shaping of the braces. A cloth patch may not appear to fail, but that may be because it has the flexibility to move with the joint, rather than actually stiffening it to the same degree as a properly detailed cap.

When I think of the strength of an arch, I think of the load being placed at the apex of the arch.

Another approach to strengthening the X might be to add fillets of wood - as the corners of some boxes are reinforced. So far I have been happy enough capping the X and still consider this to be a bit of "icing on the cake".

I have two others I will be using standard Bracing ( may do all three and use this bracing to do testing ) and use on next build if it pans out . Playing with ideas at this point .

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

"Patented Tone Enhancing X Brace Joint"! "Engineered to blah blah..... "I think you're on to something Wud!

On to the next beer for for sure !

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/