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I've always put my Neck blocks in with the end grain glued to the top and back (was told to do it this way to reduce posibility of cracking) but recently had a guitar that is out in Alberta that after only one year needs a neck reset. I had it looked at and the luthier who checked it out reported that the top and back are dimpled where the block is glued on and suggests that the Block has shrunk which is what Causes the problem. He argues, and it makes sence, that the End grain should never be glued to the top and back but rather that the end grain should be on the sides not glued. I'd love to hear other views and opinions on this.

Richard, check out this thread.

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Joe Breault
Merrimack, NH
Perpetual novice

Side grain is best for this application.
You can laminate a block with different grain directions out of small pieces or use a nice piece of Mahogany or Walnut!
The end grain should not be glued to the top ,back ,or sides !
use a slab cut piece on its side !
Mike
www.collinsguitars.com

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Mike Collins

Mike, That certainly makes sence. Does the fact that I had the end grain orientated to be glued to the Top and bottom explain the excessive shrinkage in the neck Block causing the need for a Neck reset?

Wood doesn't shrink much along its grain. It shrinks much more across its grain. In other words, it would be less likely to cause dimpling if the end grain is pointing toward the top and back. Dimpling occurs in this instance when to much of the end block is glued to the top and back. The plates move, not the end block.

To avoid this, the block should be beveled so only a section as wide as your lining is touching the top and back. No more dimples!

Ive heard arguments that glue starvation of the top or back to endblock joint can occur if glue joint is on the end grain. One well known classical maker uses a three piece laminated endblock....a vertcial grained middle section sandwhiched between horizontal grained end sections.

One solution would be to size the end grain of the endblock before glue up to reduce wicking away pof glue from the joint.

Carlton, we are talking here about Neck Blocks not tail Blocks, are you saying your neck block is only as wide as the Lineing under the fret Board? I bevel my tail blocks but not the neck block as I always thought support under the fret board was a good thing.

D'oh! I gotta start payin' more attention!

But how could the block dimple the top? It's under the fingerboard. I don't see how a vertical grain orientation could cause the need for an early neck reset, either, unless...could the block not have been made long enough to begin with? That is, was it perhaps not radiused to fit snuggly to the top and back when the box was closed? That could cause the box to start folding in on itself.

I wonder if it was too short but I have always radiused everything in the Dish. This was guitar 48 or something like that so I am glad it wasn't my first. As I said I have heard people say that The Grain should be Verticle and others say horizontal. I would love to hear the arguments that support each position.

Richard,

'Tis a puzzlement, isn't it? Yeah, with your experience I doubted it was your preparation of the block. It's the only thing I could think of, though, because wood doesn't move much along its grain.

The arguments that I've heard most for orienting the block's grain vertically are: It acts like a side brace, protecting against splitting (same for the end block); and, it presents long grain to long grain when gluing a dovetail. Of course, the latter isn't an issue if you're using a bolted joint.

That is the exact argument (side brace) that I used, yet the fellow who looked at it for me seems to take the other aproach and presented in a very convincing way (he had me convinced. I think I am going to start orientating them the other way so that end grain isn't against top back or sides. Over the next few months though my building has to slow down as Municipal elections are comming up in November and I have been convincced to Run for Mayor. Considering that are region is in the worst econmic shape it has been in in memory and everything is falling apart, what better time to get into politics

I stop the side braces short of the sides edges for that reason; if (when) the sides shrink with in the air is dry, they will not push the plates out.
One good reason for gluing the neck block with side grain against the sides and plates is so the glue joint will be good; the neck block does an important stuctural job in directing some of the loads from the string pull over to the back. This is the reason spanish guitars have a "foot".

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Rian Gitar og Mandolin

Seems you could use a high grade Baltic Birch ply to fabricate your neck block from and have it either way since each lamination is 90 opposed to the next.

[QUOTE=arvey]   I think I am going to start orientating them the other way so that end grain isn't against top back or sides.[/QUOTE]
You know, just about everything has been tried in this area, and they all seem to work, so I think you'll be okay.

[QUOTE=arvey]I have been convincced to Run for Mayor. [/QUOTE]
Wow! Well, good luck! And if you win...good luck!!!

So again, could someone present the arguements in favor of each orrientation.

[QUOTE=arvey]I have been convincced to Run for Mayor. [/QUOTE]
Wow! Well, good luck! And if you win...good luck!!! [/QUOTE]

Well I am now waiting to see if anyone is running against me. After I put my name in two others withdrew from the race (not sure why) but nominations are closed now and I am waiting to find out if anyone else entered.

IMHO
Im in favor of the traditional method. And that is
the blocks are in the same direction as the sides.
I also feel it is important to use a quartersawn block
with the qs face glued to qs sides. The concept is when the wood expands and contracts. There will be less stress on the glue joint. Yes you can put blocks in
many differant ways, but I feel the test of time is working against some of these non-traditional methods.
Best not to forget, Wood Moves!

Tom

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http://www.moriciguitar.com

Hey Arvey,OT but I like your web site, well done and some nice looking guitars.

Hey Keith, OT but congrats on your 300th post!

And Richard, go get them bud!

Thanks for the coments and the encouragement regarding politics. The funny thing that nded up happening is that the other two candidates who were running against me and take a very different approach (they want to maintain things the way they are verses developement)both Pulled out after I put my name in, and then at the last minute our Economic Developement Officer, who holds to the same positions as Myself put her name in despite saying she wasn't going to. So we have two candidates running who have very similar platforms. Almost makes me wonder if it is worth the effort.