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Hey Todd,
My necks were two piece Mahogany, fretboards Ebony, and all had been in my shop for at least several months. The waterbased glue ups were with LMI white while the neck was profiled but unshaped. Gluing surface level. Clamping was with the long Stew Mac Aluminum radiused cauls and left on for 24 hrs. I almost always got a small hump around the middle of the neck. Pretty minor and easy to level but it was there. When I switched to epoxy it was gone. I still have not decided if the benefit outweighs the mess that awaits if the board ever had to be removed.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Todd...good effort to track down experiences. Gathering the info is one thing...drawing an air-tight conclusion will be impossible but I'll be happy to provide my one and only experience. Here goes:

My first guitar was a B&S kit from John Hall. The neck came from Stewmac and it was a one piece mahogany. The FB was ebony and pre-fretted. I can be certain that the bonding surfaces are not as controlled and confirmed flat as they are today so there could be some accumulated process error along the way. I used HHG and applied it to warmed surfaces and clamped it to a radiused caul which I believe to have been flat. The neck was unclamped after 24 hours and there was a noticeable backbow. Compounding the problem was the fact that I used a one-way TR that prevented me from getting it straight. I solved the problem by abandoning the neck and starting over using epoxy, which was recommended by the 13th fret and MIMF experts of the day. They also recommended a 2-way TR.

I've been using Epoxy and 2-way truss rods ever since with success. My experience is certainly not scientific nor based on any statistically significant numbers...purely anecdotal based on a sample of ONE. I'm not suggesting that I will never use a WB glue here again...just saying that my early experience and 8 year results of my current method have shown no problems. One other lesson I always try to follow..."If it ain't broken, don't fix it."

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JJ
Napa, CA
http://www.DonohueGuitars.com

Another potential cause of movement is shaping the neck after gluing the fretboard on. Most wood has at least some tension in it and will move around when you take that much wood off. I rough shape the neck first and usually have to re-flatten 1 out of 4. And I'm pretty darn picky about the wood I use.

If anyone doubts that water in glue makes wood move around, try face gluing any two different species of .125" x 2.5" wood together and see how flat they stay. Then glue two similar pieces with epoxy. Do that a few times and maybe there will be less argument about it. But probably not

I fret my board, flatten it back out, do 90% of the neck shaping, re-flatten the surface, and glue the board on with epoxy using a flat caul. Probably 3 out of 4 necks, I don't have to touch the tops of the frets.

Just a guess but I'm wondering if those that use titebond with no problems are leveling the board after gluing?

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http://www.chassonguitars.com

I notice that several of the folks who have had bad experiences with aliphatics also fret before gluing. I don't do this, never have, so can't speak from experience, but it makes sense that gluing a backbowed fretboard (as it will tend to be from the interference fit of the frets) to a thin, partly-carved neck could result in a "warped" neck. Epoxy's thicker glue line and higher resistance to creep might reduce or solve the problem.

My process is very similar to Kent's and my results are similar as well. I have not had to touch my frets on the last 4 guitars.

Greg

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Gwaltney Guitars

My neck and fretboards that I glued with titebond were clamped to a 2" thick oak flat caul. I ended up with a slight backbow that was easily sanded out or adjusted out with the truss rod. Now, using Smiths Wood epoxy and same caul, I don't have any backbow whatsoever. I feel much more comfortable using the Martin one way truss rod now.

Chuck

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To respond to Rick's post, Kent stated he flattend the back bow out of the fretboard before glueing to the neck so likely not a factor. I would bet money JJ did the same......maybe he will chime in.

I hope to try my first very soon.....maybe this weekend. I will fret the board (maybe today) using fish glue and clamp the fretboard flat on a 1 1/4" thick piece of granite till the glue is set. After 24 hours, I will work the board bending it against the bow with clamps till the board will lay flat for 24 hours then glue the board to my 5 piece laminated neck (mostly mahogany). I have a couple of the longer STewMac Maple cauls with a 16ft radius that I will use for glueing. I'll set these upside down on the granite block, turn the neck/fretboard upside down so the frets sit on the maple cauls, and clamp for 24 hours. The granite should keep everything level. I'm still leaning toward epoxy for this. I'm trying to minimize the amount of fret leveling neeed.

How often is a fretboard pulled........1 out of 100?

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Formerly known as Adaboy.......

I assume you're asking because you think epoxy is harder to release than aliphatic? If so, that's incorrect unless you're using a heat resistant epoxy. If anything, it's easier to get apart.

Sorry, I know this has been beaten to death in past threads but as for backbow induced by fretting, it doesn't matter whether you fret before or after the board is glued on. Either introduces the same compressive forces. The difference with pre-fretting is that, if you want to, you can flatten the board back out before gluing to the neck.

Seems to me this is just another one of those areas where there are many different ways to do a fine job and you just have to pick a method and work out the bugs.

I will say that if I were using glue with water in it and flattening the fingerboard after glue up, I would wait as long as I could (like a month) before flattening. In my experience, it takes a long time for a neck to equilibrate after water is introduced, even if it is a tiny amount.

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http://www.chassonguitars.com

For a few years now, I've been fretting based on a technique that Mario showed us. Darryl and Kent must have been listening as well. The key really is to get all surfaces dead flat, level and as relaxed as possible. If all of that is accomplished successfully then the likelihood of getting a wonky neck is reduced. More importantly, If one installs the frets on a dead flat board then the likelihood of having to level is minimized or eliminated. After installing frets (I also use FG), I clamp the center of the FB with up to 1/4" blocks at each end to overcompensate for the natural bow of the fretted board.

Using this technique successfully was important for me to practice since I have been using SS frets...and I really want to minimize the amount of work I put into the much harder material. My last 5 fret installations (hammered frets) have been much easier as a result of following Mario's method.

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JJ
Napa, CA
http://www.DonohueGuitars.com

I was listening but he was preaching to the saved

One thing I did get from Mario that has helped was his technique for carefully checking the press fretted board with a standard short straight edge and lightly hammering down any high spots. I had always gone over the press fretted board lightly tapping a hardwood block that spanned a few frets. I was surprised to still find some high spots but I did.

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http://www.chassonguitars.com

Some great info on the thread . When I do a neck , I do a fretted board but I also use a granite plate to glue the fretboard on to the neck with. This allows total control of the gluing plane. One thing that is a big variable is clamp pressure. I use about 8 to 10 bar clamps and will move them around every few minutes . I am using Martin's 2 way truss rod for the most part. If I am using a 1 way rod I like to glue up the neck with about .020 forward relief in it. I do this with aluminum bars for cawls and a feeler gauge under the 7th fret. That way I can adjust the one way rod to pull the neck flat . This allows me forward adjustment if needed.
When out at Martin a few months ago , they redid all of the neck gluing machines and went from screw clamps to pneumatic cylinders. The engineer said that they are looking for a better control of even pressure.. So if I may add a point to the original post, what is everyone's clamping technique. Often the end result is caused by something in the process itself.

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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

I also do the clamping thing to compensate for the fret induced bow, I have a sanding block with a 15' radius that is a little longer than the fret board. I clamp the board in it for a couple days, when it comes out it is bowed the other way but after a short while it flattens out real nice. The force probably forces the tangs to bite into the slots so there is less tension on the board. It does not seem to matter if this is done when the glue is still wet or has dried the results are the same, though if clamped wet the board has some cracking sounds when straightening out and if done with the glue dry is makes the cracking sounds when clamping. I use thinned titebond in the slots when fretting.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

My students and I use TB. My fingerboard is tapered and thicknessed, but not yet finish levelled or radiused. My neck blanks are still very thick, and are still wider than the FB and rectangular. I use 6 or 7 clamps and apply a fair amount of pressure using wooden cauls. i dont really see much bow after taking the clamps off, even if there were, it all gets taken acre off down the road when i level and radius. The heel gets shaped and then teh neck is fit fairly close to final position before the inserts for the bolts get put in. Then I fret. After that is done, then I start to final shape the neck.

The whole process usually takes a few days, I am in no rush (with students, it can take a few weeks to do all this at one night a week). Cnat say I have had any amjor bowing or twisting probs doing it this way. Of course everything stays in the same environment as this happens.

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

My first was done with titebond with no problems (long LP junior neck)
Then I read how epoxy was the go and used it for subsequent instruments.
Then I was faced with repairing a flamenco guitar which needed a new fretboard and I did not want to be cleaning epoxy squeezout off finished surfaces. So I used HHG and warmed the surfaces with a heat gun, but did it for about 6 minutes so that the surface was not only warm, but dry to counteract the moisture it would absorb during glueup. This worked fine on this and 2 subsequent instruments.
All done with boards fretted before gluing and with a full length caul.

I do it the Benedetto way, which is more or less the same way as Tony using Titebond. Laminated necks, fretboard glued on to thicknessed but unshaped neck, radiused and flattened, frets installed, neck cut to width and carved. Never had any bowing problems and my first 5 had one way rods.

My necks are homemade, mahogany usually, with a center spline of hardwood -- koa, maple, walnut, rosewood, etc. -- that works visually with the rest of the guitar. Sometimes I'll add a veneer strip on either side of the spline.

I use CNC'd fingerboards, acclimated to the shop over at least a month (usually several). They're radiused and tapered. I glue to a carefully jointed neck, roughed out on the bandsaw to around 5/8" thick at the nut. Carbon rods on both sides of the 2-way truss rod for all long-scale necks, not on short scale 12-fretters. The fingerboard is placed on a 3" X 3" aluminum extrusion that was surfaced to plus or minus .001", with a radiused caul to make sure the edges have good pressure.

The gluing surface of the fingerboard is freshened with a scraper or sandpaper, just enough to get a fresh surface.

For glue, I use aliphatic, either LMI or Titebond. I've used hide glue but don't think it's worth the bother in this application. The fingerboard is located by 3/16" dowels in the same places Martin uses steel roll pins (my drilling jig was made to allow the use of Martin 'boards). Clamping is a pile of cam clamps -- at least 6.

I level and fret after the neck is finished and attached to the body. This is the way I learned and have had reinforced by luthiers I know and respect. Not to say it's the only way, just that for us traditionalists, it's the way we prefer.

To date, no twists or warps. That's a sample of close to 200 instruments over 18 years. I level with enough tension on the rod to create a slight -- very slight! -- backbow. The compression of fretting seems to be just about in sync with the string pull so I get good relief with slight tension on the rod. Leveling and creating an upper fret drop-off (0.020" approx.) takes only a minute or two with 80 grit, then up to 320. Chamfer the slots, finish with 400 and 600.

I agree that there is more than one way to do this and more than one suitable adhesive -- each will have its own advantages and disadvantages. I also agree that different procedures, clamping methods, etc. can have a big impact. But I remain unconvinced that the tiny amount of water in the glue has ANY effect whatsoever. Laminating is what I've done since making furniture in the late Sixties, through years of small boat building and repair (both wood and composite), and now 18 years of guitar making. Glue is weird stuff but not that weird.

Basically do the same as Rick. F/B's are around 5/16" thick before radius. Straighten after glueing to neck on the 6 X 89 sander and rough the radius. Finish radius and straightening after finishing and glueing on box. Rout a very slight bevel in the fret slots and tap & glue in with TB or LMI.