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I’m at a loss here...Top & Neck Blk? PICS http://www-.luthiersforum.com/forum/viewtopic.php?f=10102&t=6898	Page 1 of 1

Author:	Dread1916 [ Sun May 28, 2006 2:42 pm ]
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I'm in the process of fitting a top to my rim and had to trim the top most tone bar to accept the Neck Block tonge...I went back to my plans (after I started cutting...DOH) and the Neck Block on the plans is smaller and does not have a tonge so no need to trim... Has anyone seen this before??? I don't think this is an issue since the fret board and top are still supported in this area, but, I just don't want to have an issue with cracking around the finger board / Top joint. Take a look at the pics below and let me know what you think. The bracing and neck block are from Martin...Plywood Neck block (cough..first build...cough) and the bracing is a standard Dreadnought per the Martin plans...did I get the wrong Neck Block from Martin??? Thanks for ANY help on this one... JP See the above area in Red that I have now removed... See the neck block with tonge... Let me know what you think... JP

Author:	Michael Shaw [ Sun May 28, 2006 2:45 pm ]
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In Frank Finochios video he romoved the section you got outlined. He used the same type of martin style block . He worked for Martin. So I guess he knows what he's talkin about...Mike

Author:	Andy Zimmerman [ Sun May 28, 2006 3:05 pm ]
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I also use a fretboard extension piece on top of the neck block. In doing so I don't use that top flat brace. BUT I position the upper transversal brace so that it butts up against the fretboard extension on the neck block. I actually glue them together. Make sense!!!

Author:	RCoates [ Sun May 28, 2006 3:18 pm ]
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Some people pay good money to have that "popcicle" brace removed from their Martins... Don't forget to cap that X brace joint.

Author:	Michael Shaw [ Sun May 28, 2006 4:16 pm ]
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RCoates in your oppinion is it just better to leave this brace off all together...Mike

Author:	Rod True [ Sun May 28, 2006 4:24 pm ]
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What's so wrong with plywood? It's strong and light. The neck block and tail block add little if any to the acoustics of the instrument on whole. As you can see from your neck block, there are two angled grooves in it. That is for a different brace layout, the two sound hole braces usually (with this type of layout) run through the large upper transverse brace, into the head block at that angle, some call it an "A" frame upper brace pattern I think. I also believe that using the "A" frame pattern elimiates the "popsicle" brace or the first picture you have marked up. As Ronn pointed out, don't forget to cap the x brace joint (green circle) You also may want to add a small "cap" over these other two areas (blue circles) as it appears that the center seam is opening, Is it?

Author:	RCoates [ Sun May 28, 2006 6:22 pm ]
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Should you take the popsicle brace out completely or just enough to fit your neck block in place? I really don't think you'll see/hear a whole lot of difference one way or the other. There is of course a question of future top cracks. Not a big worry given your chioce of neck block IMO. Personally with the neck block you are using I might leave the popsicle stick out. As Rod said it is for a different bracing pattern than the one you are using. John Hall or some of the other more experienced builders could probably give you a better answer. My own experience is somewhat limited. Have a look here and you'll see the different Martin patterns... Martin Bracing

Author:	Dread1916 [ Mon May 29, 2006 5:23 am ]
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The good news is that the top seam is not a opening up...its just pencil marks for the Center Line...thanks for the concerns...(you did make me swallow hard and run to check the top)... I think that I will be filling the Neck block channels with stock (of course leaving the truss rod channel open) and just attach the top to that (and the kerf lining/rim) Thanks for all the help... JP

Author:	Kevin Gallagher [ Mon May 29, 2006 3:12 pm ]
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Dread, You're obviously working from a Martin kit or at least from Martin parts since your top has the locating tabs at the waist from the plant. The problem is, though, that whoever made up your kit at the North Street shop threw in a neck block for the hybrid "A" frame bracing that was designed whlie I was working at Martin back in the early 90's, but failed to give you a top bracing set to match and went with the traditional bracing system. In order for that to work, you have to remove the section you have highlighted. Keep the brace in there for support in that upper bout area even though you have the additional support offerd by the tongue on the block. With traditionally braced Martins, it is important to have that brace intact since it provides to only support for the fingerboard tongue besides the minimal amount that the top contributes. It grain runs perpendicular to the top's grain and the two provide a very stable resistence to the tendency of the fingerboard to dive in that area causing cracks that run from the corners of the board to the soundhole....a repair that I've performed amny times on Martins...many of which had the brace removed. The upper bout is very rigid and isn't nearly as big of a contributor to the guitar's tone, response or volume as the larger lower bout and that brace doesn't impede tone at all while offering critical support. In your case, with a mixture of both bracing system applications, the brace isn't nearly as critical or important, but leaving it won't affect the tone. Regards, Kevin Gallagher/Omega Guitars

Author:	Dread1916 [ Tue May 30, 2006 12:48 pm ]
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Thanks Kevin...I think that I'll be taking your advise on this one and just leave the neckblock alone (only adding some material to "plug" the "A" slots) I've already cut the recess in the top brace as shown in my doodle above. So I think that I'm going to be OK... Thanks again, JP

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