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Butt joint bolted neck
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Author:  Wes McMillian [ Fri Nov 09, 2007 3:15 pm ]
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For those of you who do a straight butt joint bolt up neck (versus M&T), how thick do you make your neck block? I still have plenty of barrel bolts for a knock-down M&T joint, but I'm considering trying this. I like this mostly for its simplicity but I can see side benefits as well (slight weight reduction, more vibrating area of the upper bout).

As part of my process is trying to free up as much of the upper bout as I can, how are y'all supporting your fingerboard extension? I know many do an integrated extension into the neck block for support. What do you think about just a couple of braces, running parallel to the fingerboard edges, and inlet into the UTB and locked into the neck block, making it an integrated unit? Does anybody do something like this?
Author:  David R White [ Sat Nov 10, 2007 1:58 am ]
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Mine are 1 3/8"...I don't think you can really go smaller without some structural risks unless you provide some other type of support.
Author:  John K [ Sat Nov 10, 2007 2:04 am ]
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Unless you plan on floating your fingerboard extension I think you might as well provide ample support for it with an L shaped block. There is not much transfer of energy across the soundhole (which helps uncouple the lower bout from the top and that fact coupled with the rigid FBE pretty well makes that area ideal for structural support. IE, I think you would loose more in stiffness and sustain than you would gain in volume and tone.

Of course other perceptions are out there

John
Author:  Mattia Valente [ Sat Nov 10, 2007 3:37 am ]
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I'm using a 7/8" thick headblock on my current guitar, but it does have a spanish foot (L shape extension for the back), and will have CF 'flying buttresses' running to the waist. Should be plenty strong enough to support a neck since I'm not planning on recessing my neck bolts.
Author:  grumpy [ Sat Nov 10, 2007 3:54 am ]
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Other perception here. I don't see the need for the supporting neck block. and some of that energy in the neck does make itself to the body, unless we stop it in its tracks with a heavy block or heavy bracing. IME.... Many ways to approach everything.

Neck block is around 1-3/8" to 1-1/2". I glue the fretboard to the top, but with only two narrow "strips" of regular white glue. With this setup, if the fretboard shrinks if dried out, there's hope that the glue will creep or let go, saving the top from cracks.
Author:  Wes McMillian [ Sat Nov 10, 2007 4:35 am ]
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So, Mario, am I to understand that you use NO bracing north of the UTB? At all?? I, too, was thinking the full FB supporting block may be overkill ("may" being the operative word here. With my limited build experience I don't want to sound like I have some supporting evidence for this, just conjecture...), but I was thinking something would be needed - hence my thoughts on the two braces locking the UTB and the neck block together.

Do you use a solid neck block or ply?
Author:  Rick Turner [ Sat Nov 10, 2007 4:56 am ]
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With flying buttress bracing of the neck block, you can take it down to 1/2" thick Baltic birch and then use very little bracing in the upper bout. The neck block and bracing don't have to support the fingerboard at all. Your bracing in the upper bout can just be there to support the top a bit and be totally designed for the tone you're after.

I cantilever the fingerboard off the top, and you can do this either with a butt joint or an adjustable angle neck arrangement.

There will be some very nice photos in an up-coming issue of Fretboard Journal on how we do all this.
Author:  grumpy [ Sat Nov 10, 2007 4:58 am ]
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No, I use a pair of smaller braces at an angle. Must be a photo somewhere in my construction/buildup pages...

I laminate my neck blocks from two pieces. I basically do a "flip" match. Just prevents a split from following a grain/or weak line. I use spruce or western red cedar for the neck blocks, BTW. used to use mahogany, but that was overkill, methinks.
Author:  KenH [ Sat Nov 10, 2007 5:03 am ]
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I do my blocks the same way as Mario, and I use the butt joint method. My block is 1 1/2" thick. As far as other support, the transverse brace and the flat upper bout brace should add plenty of support and also help keep any cracks from occuring. I use titebond for gluing down the fingerboard. so far I havent had any problems with this arrangement. I made a template for drilling the holes for the bolts and also for the hole for the brass inserts and they line up perfectly.  I try to use 2 bolts in my necks, but I have found that one bolt holds without any problems.


I have tried dovetail joints (wont do that again) and also the M&T joints. By far the butt joint is the easiest to use and also getting the neck to lay flat on the top of the guitar is easier for a tight joint.


 
Author:  Rick Turner [ Sat Nov 10, 2007 5:20 am ]
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If you're not using flying buttresses to support the top of the neck block, be very careful about under bracing the upper bout. I've repaired too many instruments where braces loosened (heat or whatever), and shear cracks appeared on either side of the fingerboard, and the guitar started to collapse in on itself.   

You might consider a couple of cross grain strips kind of like back seam reinforcements that would go between any transverse upper bout braces and span the line of the fingerboard edge.   That would tremendously reinforce the top against shear cracking and yet would not add significant weight.

I don't bother with that because the whole issues is taken care of with the flying buttresses, but that has been my repair strategy on guitars that came in collapsing. This is one of those things that you have to see as a repairman to really understand. I've seen guitars with massive neck blocks..."L's" and "U's" and big transverse braces...and still they collapsed.
Author:  Wes McMillian [ Sat Nov 10, 2007 5:26 am ]
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Ah, I remember your angled braces, Mario. That's what led me to do something similar on my last, but with a bolted M&T. And no popscicle brace, of course.

Spruce or WRC neck block, huh? Cool! With all the little weight-saving measures you build in, I bet you have to tie those guiatrs down to keep 'em from floating off!

Rick, I'm looking forward to your article. I've followed the discussions on flying buttress bracing with great interest. Seems like a perfect all around solution. Only downside I see is the less-than-conventional look when building for traditionalists. Other than that, I love it!
Author:  Wes McMillian [ Sat Nov 10, 2007 5:33 am ]
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Yeah, Rick, your last comment about the cross-grain strips under the fingerboard edges sounds exactly like what I was describing - except I was picturing something more akin to finger braces. Marios is basically this, as I recall, but run out at an angle, splayed alongside the neck block, where I was thinking about inletting them.

Thanks!
Author:  Rick Turner [ Sat Nov 10, 2007 5:42 am ]
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Let traditionalists pay for traditional repairs...

I've not had one single potential customer complain about the looks of flying buttresses.   In fact, their eyes light up, and it's an "a-ha" moment. Customers love the idea that thought is going into solving problems that appear in guitars. Hence the inclusion of truss rods in practically everything that isn't a slavish reproduction.   Truss rods are not traditional... And depending on where you want to go historically, geared tuners aren't traditional, either.   Come to think of it, steel string guitars are not traditional...

Traditions all start somewhere in time. Why not right now?
Author:  grumpy [ Sat Nov 10, 2007 7:22 am ]
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I'm not arguing the worth of the buttresses at all, as I think they're a great idea and surely open up new directions in bracing, but there are millions of "traditional" guitars with zero issues built the old way, also. Tons of old, pretty lightly built Martins and Gibson's that were less than cared-for carefully. On my own front, I haven't seen any inclination to imploding on anything I've built in the past 11 years. And while I haven't sent any to Antarctica, I happen to live in a sub-arctic climate(our town's record cold temperature is -73°f), and have, and so have some of my clients, lugged my instruments around in sleighs, behind snowmobiles, in temperatures exceeding -40, on our way to our bush camps for weekend outings. So cold we top up the camp's  100 lb propane tanks by pouring the now liquid propane from smaller, more portable 20 lb tanks!(instead of hauling the 100 pounders back and forth). I've even tossed my own guitar and mandolin in the front seat of my truck in extreme temperatures, overnight, and took them back inside the next day for a super fast warming. Apart from the shattered finish on the nitro finished ones, not a single glue joint has ever let go on these, nor has any of them imploded, nor do they show signs of imploding whatsoever, while at the same time being very lightly built.


So, while there's nothing wrong with the new ways, but there's also a lot to be said for the old timey stuff, too, if done carefully and correctly.
Author:  Rick Turner [ Sat Nov 10, 2007 7:57 am ]
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Yeah, Mario. I also believe in job security for guitar repair techs. Don't we love those action jobs and neck resets to make the mortgage or rent payments?... Build 'em the old way for the luthiers of the future to fix.

You talk about tons of old pretty lightly built Martins and Gibsons. Most that I've seen have had some version of lowering the action done, whether it's filing and sanding down the saddle to the point where it's barely sticking up above the bridge or sanding down the whole bridge itself.   And that's before we get into resets.

I started the flying buttress thing way before I got the commission to build Ms. Antarctica, and it was in reaction to real world problems with guitars (and a couple of Gibson mandos) that had collapsed in upon themselves through "normal neglect".   That got me to thinking about the "why" behind neck resets...which according to guys like Frank Ford are practically inevitable for steel string guitars...it's not a matter of "if"; it's simply a matter of "when".

Then there's the issue that the loved vintage instruments that are around are the survivors...the ones that either were lucky and inherently stronger (Darwin approach) or the ones that were taken to decent repair techs along the way. Many of the broken ones have been discarded along the way as they went down the ladder of usefulness for anyone.   Plenty of otherwise decent guitars have been turned into land fill because they became too hard to play and the owners didn't know any better than to toss it or put it up in the attic for further deterioration.

With a bit of luck, most of the current crop of modern luthiers will be dead before their guitars need neck resets en mass, but need them they will. All you have to do is look at the need for neck resets on steel string Martins from the late '20s on forward. For that matter, look at the rather high percentage of neck resets needed on some modern Martin inspired guitars like those from SCGC. Build them light, put light to medium gauge strings one them, and they'll start to move. The backs flatten out, the neck block rotates forward, the neck angle changes, and the action goes up.   That's not talking at all about changes in the top below the waist; that's just the overall geometry of the guitar.

Mine won't do that. I believe I've solved the problem, and if someone wants to raise or lower the action, it takes two Allen wrenches and about 15 seconds to do.

I've repaired, built, and worked on literally thousands of guitars now, and I've learned something from every one, and one of the things that I've learned is that there are better ways to build for the present and the future. I don't discount the knowledge of the past one bit, but I'm not bound by it either. My heroes are the guys like C. F. Martin, de Torres, and Lloyd Loar, all of whom learned from the past and then moved forward into the future.

I cannot stress enough how important I think it is for modern guitar makers to gain experience repairing guitars.   Broken guitars really make you think about how to make better instruments.
Author:  Brad Goodman [ Sat Nov 10, 2007 10:37 am ]
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I think that Jeff Babicz's guitars have really worked out most of these problems.
You can adjust the neck height(action) relative to the body without the guitar going out of tune- in seconds.
By the use of his patented "lateral compression soundboard",the stress of deforming the top is virtually eliminated.
Author:  grumpy [ Sat Nov 10, 2007 10:45 am ]
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I hear you, and that's why I bolt my necks on. Dovetails actually were faster and easier to build.

we have to strike a balance. You found your balance by engineering a upper bout system that you hope solves the problem. As long as the CF doesn't creep(compression is where its at its weakest) or the rod's end don't compress int the block(s), and as long as the backs don't flatten, all should hold. You've found your comfort zone in your system.

I simply found my comfort zone in building an instrument that will be easy to reset when the time comes, and it will. 15 minutes of adjusting once or twice in its lifetime isn't terrible, especially at the numbers I'm putting out. I do do a few things to stiffen the upper bout, things like my doubling of the ribs from waist to waist(don't go looking at my build pages, as I wasn't doing it then <g>) and solid linings, and my use of hide glue. That's my comfort zone, and I'm comfortable with it. It is serving me rather well....

 The examples of the surviving old Martins and Gibsons is a bad one; up until 10-15 years ago, a neck reset was still a mystery. Today, it's common knowledge. Today, we don't hack up guitars with all sorts of 'fixes' like they did then. Ad we also know from te past 5-6 decades that they don't require resets at regular intervals; once the body has taken its 'set', they hold that set very well.

While we must keep warranty work in mind, we also mustn't let it dictate all of our design goals.

Author:  Rick Turner [ Sat Nov 10, 2007 11:29 am ]
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Jeff's approach on the neck is great. As for the splayed strings behind the bridge...well, I'll just let the market place and guitarists of the future decide that one. I'm not going there; it's not my cup of tea.   Ned Steinberger did that before Jeff, and Steve Grimes made some instruments that way.   It didn't convince Steve to change his guitars to that bridge system.   I think it may be a solution for a problem that isn't there. Also, for flat top guitars to sound like flat top guitars, they may just need that torque and pull on the bridge.   Flattops with tailpieces (Stella 12s and Macaferris excepted) have never done much for me or most guitar players.
Author:  Heath Blair [ Sat Nov 10, 2007 12:51 pm ]
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wes, im not sure if this is what you were referring to in your original post or not. either way, heres a view of what martin does on their lower end "1" series guitars. scroll down towards the bottom.


http://frets.com/FRETSPages/History/Martin/MartinBraces/mart inbraces.html
Author:  Wes McMillian [ Sat Nov 10, 2007 2:40 pm ]
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Actually, that does look similar, Heath. I have seen that but forgot about it.

Here's a pic of the Martin hybrid bracing, same as the D-1 in the upper bout. Tall soundhole bracing extends through the UTB and is inlet into the neck block.

Author:  KenH [ Sat Nov 10, 2007 3:36 pm ]
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I dont know if this is necessarily on topic, but believe it or not I have a comission coming up that is going to prudo bay (not sure on the spelling) Alaska. From sunny Florida to Deep freeze Alaska. It is a long story on how I got this comission...


I have been wondering if there is anything in particular that I should do to this guitar that I dont normally do?

Author:  Rick Turner [ Sat Nov 10, 2007 3:49 pm ]
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"Exxon" inlays...
Author:  Steve Saville [ Sun Nov 11, 2007 10:45 am ]
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[QUOTE=Rick Turner] ......I think it may be a solution for a problem that isn't there........[/QUOTE] That's my take on it also.
Your flying buttresses are on the other end of that spectrum. You've been talking about that article for some time now. I can't wait to see it.
Author:  dberkowitz [ Tue Nov 13, 2007 12:34 am ]
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Is courtesy of George Lowden who was doing that A frame around the
soundhole long before Martin introduced the D1 in which it was introduced.
George doesn't use the flat braces in place of fingerbraces but runs a single
brace that follows the lower arms of the X brace.
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