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My personal guitar (a GV Rubio Torres classical) even has an extension where the heel block (Spanish cedar) meets the back. In other words, it projects onto the back about 3-1/2" apparently to provide a better fulcrum. It is one LOUD guitar and one of the sweetest sounding you'll ever hear regardless of price.

For what it's worth, Steve

I just saw a "custom" hand built guitar that did not have sufficient contact on the back of the guitar under the neck block and under string tension for a week, the neck began to pull the neck block out of the guitar from the back like a big lever.
I felt really bad for the owner 'cus this builder was bad. It looked like he had no idea what he was doing.
Anyway, full contact for me.

-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

I do what lance, and many others do. full contact on the neck block, but I
chamfer the end block to be the width of the linings, and tuck my back
reinforcement up to the block....

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John Mayes
http://www.mayesluthier.com

I'm full contact at both neck and heelblocks. I can't think of a reason not to.

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Jimmy Caldwell
http://www.caldwellguitars.com

full contact here too!

Ok, I'll bite too. Not only do I glue the whole thing down, but I add a foot to help counter the torque that the neck applies to the neck block.

I feel this transfers some of the force to the back and there is less chance of a twisting motion which would result in neck resets.
It's worked so far but I'm only 5 years out. Time will tell.

Hey Paul, what are your thoughts on grain orientation? I notice that with your block you would glueing the top and back to end grain. I turned mine on the side so that I would avoid that. Although, as mine is a cutaway, one of the sides is now glued to end grain.

Thanks

Shane

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Canada

We also want to see more of that guitar Paul. Three piece back? Quilted maple? Nice linings also.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

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Nice idea Paul! May I have it?

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http://www.presnallguitars.com

Please more pics of this build Paul!

Serge

Paul, I really like your design...it makes sense. From the little I understand, that part of the guitar is not a big sound producer anyway.

Philip

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aka konacat

If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

Paul, you went to some of Charles Fox's classes, right? He also uses (or used to use) a version of a "spanish foot" on his laminated heel block to acomplish what you are talking about; was he the inspiration for your design? I think it makes sense, but I also wonder about the grain direction...?

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Rian Gitar og Mandolin

Arnt, yes I studied with C. Fox and worked for him for a short time. It's painfully obvious that he is a major influence in my building. But he does a lot of things that I think are superior.
Here's a drawing of the neckblock that I use. It's 5 peices with the grain oriented in ways that are 1)strongest and 2) there is minimal end grain gluing. So the "feet" have grain running horizontal from neck to tail. The block runs vertical from top to back in the direction of neck to tail. The small block is there as a stop when I cut the tennon but is rotated so that it is longrain against the back of the guitar.

I add a "Spanish" foot, too. It's the anti-McKnight strategy. But I don't make
the block out of construction 2x4 like that Woolson character. {;->Howard Klepper38745.6228703704

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

    Martin never applied that taper to cut cost or time in the radius dish...which by the way, is performed by machine and not by hand so the time issue is not applicable. It was suggested when I was still employed there back in the beginning of the 90s as a means to minimize contact between the back and the block on the newly introduced plywood models with laminated backs and sides. The tone wasn't that of a solid wood guitar and the goal was to coax that little bit more out of the laminates. That was the reason for the minimal contact which ends up being about the width of the contact area of the sides and kerfing all the way around the rest of the body's perimeter. The transverse bracing system wasn;t arrived at until two or three years later as an answer to any movement that may have been made possible by the less resistent block glue surface on the back.

It was a practical idea for getting a little more out of the lower quality laminated backs for tone by freeing as much of the surface area up as possible, but a possible compromise in the integrity of the overall joint....or they would have switched to it on all of their models eventually. That's not on the horizon, I can assure you.

   Tim McKnight is obviously creating the rigidity necessary to balance the application as part of a system of support since he has enjoyed a good long run using it. It's obviously not hurt his tone at all from what I hear about his guitars.

Regards,
Kevin Gallagher/Omega GuitarsKevin Gallagher38746.0294560185

"And now, the rest of the story" Paul Harvey

Thanks Kevin for enlightening us all.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Paul, so this is an "all bolt on system" where you also bolt the fretboard to you neck block assembly, yes? The grain direction I wondered about was the in neck block itself, the part that is glued to the sides. If the sides shrink with humidity, won't the block (with opposite grain direction) push the back and top/fingerboard out? Oh, and in your axionometic veiw it look as though this part is glued up of 4 pieces, but you picture shows a solid block; that's just a CAD thing, right?

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Rian Gitar og Mandolin

I glue full contact on the neck block, but taper the top and bottom of the tail block to the width of the kerfing. reason being - when the top starts to move over time, especially on the softer wood of the top, the block will telegraph its footprint right thru the top.(and if the top moves enough, it will cause wrinkles to appear out from the corners of the block) I dont like the way that looks on a guitar , so if you taper it back, it can only look the same as the rest of the guitar, like its kerfing. Way back there you dont gain anything strength wise anyway IMO, so why bother to leave it. It also restricts the top in that area, which is the area critical to bass response - the loosness of the top at the edges. I do it to the back to be consistent.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I do the same thing, Tony. I also laminate the tail block, and the part with the grain running oposite of the sides will be the beveled one.

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Rian Gitar og Mandolin

Thanks for the real story, Kevin. My hunch was what it was, a hunch. A calculated guess, but wrong nonetheless...

Is it also safe to assume the plywood back and sides are also more ridgid than their solid wood counterparts?

So, when shall we see you start undercutting your blocks <bg>?

Not only are the laminated back and side materials more rigid than their solid wood counterparts, but the sides are actually bent during the lamination process so that the glue joints between layers dry while bent which adds to their stability and strength and the backs are laminated to their radius which locks that in somewhat, too, adding to the stability and strength in them.

   I don't plan on moving to any laminated woods so I'll not be switching to a tapered block either. I don't want to adopt any variation on Martin's hybrid cantilever design to compensate for its use either so I'll stay put for now. I am prototyping a few models including a new upper bout bracing system that will add signifigant resistence to the pull from the neck that tries to collapse the body of every guitar.

    Oh...and as far as those wages go for the workers on the floor of a guitar factory as compared to Canadian dollar earners...it's an "apples and oranges" thing when you're talking American dollars and Canadian dollars being earned and spent in their respective economies. I have a few friends in Canada making a great number of dollars per hour, but they don't go any farther than less American dollars per hour do here. It's a moot contention.

Regards,
Kevin Gallagher/Omega Guitars Kevin Gallagher38746.7995023148

It is indeed glued up of four different pieces. That's how I can manipulate the grain to go the direction I want in all the pieces.

Not only are the laminated back and side materials more rigid than their solid wood counterparts, but the sides are actually bent during the lamination process

All of which makes for a more stable neck block area, which can get by with less glue surface. As expected...

Thanks!

I didn't expect to see you switching, which is why I put the 'big grin' part(<bg>) in the line.