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For those that shape the neck after the fingerboard is glued on, you can just glue (a drop of CA) some small wood locating blocks (binding scraps or smaller) to the neck blank, since there's usually 1/8" or so of excess neck showing.
I used to use pins through the fret slots (works well) but the wood blocks are less trouble and I don't have to work the caul around them or worry about removing them (if you forget to pull them once things are stabilized with the clamps) .

Lots of ways work for this. The 'dowels under the fingerboard' seems to be the way Martin is doing it, since some Martin fingerboards I've got have the divots drilled in the underside of the board. Something to keep in mind if you are taking off a fingerboard and the palette knife comes to a sudden stop!

Cheers

John

Having participated in the making...well actually I did all the rough shaping...of about 1,250 Alembic necks where we put the fingerboard on and then shaped, I can tell you that you'll have a much more stable neck if you rough carve first, allow the neck to relax and stabilize, and then do one last check on the straightness of the fingerboard gluing plane, correct if needed, and then glue on the fingerboard with a non water-bearing glue.   When I stopped shaping blanks with the fingerboard in place my neck problems dropped by an order of magnitude.   

Whenever you plane or shape a piece of wood and remove more material from one side than the other, you get stress release and wood movement. This applies whether you are resawing blocks into tops, backs, and sides or you're making necks. If you rough shape your neck parts, let the wood sit a while, and then correct and glue and final shape, you'll have a lot fewer problems down the line and you'll have happier customers...If you care about such folks...

Rick makes some good points. I'm not sure I have the skill to shape a neck without having the fingerboard in place. Experience counts.

I should have added that I also flatten the fingerboard and install frets after the neck is shaped, sanded, finished, and attached to the guitar. I also use laminated necks, though they may well show as many stress-related problems as traditional necks.

BTW, the polyurethane glues need moisture to cure, so they may be pulling enough moisture out of the neck to cause problems as well. Epoxy (as suggested by Rick T and others) is the way to avoid any moisture problems.

John

Taylor puts blanks through the rotoshaper (rough shapes them), then glues on the fretboards, then machines them to final profile under tension (truss rod active). Not sure how this fits into the mix, but I figure it was worth bringing up since they put out over 1200 guitars a week.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Unless Taylor has changed the neck machining process drastically in the past year, they do not use any of the rotary shaping methods used traditionally by gunstock makers. They shape blanks on Fadal CNC machining centers. But yes, they preshape and then glue. I have some unsanded Baby Taylor necks here that Bob gave me to check out, and that's how they were done.

Yep, that's a great way to do it. We have the same thing only in PlexiGlas and because we use it on different width necks, we work off of a centerline for the fingerboard rather than the rails that need the same fingerboard taper every time. We use a brad point bit.

[QUOTE=Hesh1956]Chris I have a ton of System III too that I have loved to use for pore filling. On the last guitar I was concerned that the stuff was 1.5 years old, at least in my shop......, so I checked the FAQs section of System III's web site looking for the manufactures indication of shelf life. I was less than pleased in as much as they provide a cryptic answer saying that the enemy of epoxy is UV light. They go on to say that if the epoxy is kept in a cool, dark place it should be OK for a year....... Any way knowing as I do from the many examples that have been posted of System III being very sensitive to mix ratio, Mike Doolin's published tutorial, and the need for a gram scale when mixing SIII I just went out and bought some fresh Z-poxy...... I don't know if SIII was trying to scare customers into buying more, fresh product or what but they do specifically indicate that they do not recommend using it much beyond a year. That scared me off. [/QUOTE]

Hesh, I agree that they may be trying to sell more product, or, when putting it in writing would like to be very careful about their claims. I spoke with someone at the factory when I got the advice on use and life. The sysIII epoxy I purchased from the retiring woodworker was already several years old... that was four years ago and I am still using it. I do find that I have to pay special attention to the mix and have purchased a scale to help in this endeavor. If the zpoxy is easier to mix, I may try it out if I ever run out of the sysIII on hand!
chris

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

It's not that big a deal to use a triple beam balance scale for metering out epoxy ratios even though people visiting you will think you've joined the drug trade. Just remember to compensate for the weight of your mixing cup. We use yogurt containers for that. The Smith stuff is a 5:6 ratio by weight, and you have to get that right as one part is a bit denser than the other so going by volume doesn't work.

[QUOTE=Rick Turner] Unless Taylor has changed the neck machining process drastically in the past year, they do not use any of the rotary shaping methods used traditionally by gunstock makers.[/QUOTE]

I'm not familiar with the methods you speak of. The rotoshaper is a machine they built on site there. It runs necks constantly through a series of shapers on templates to put a chamfer on the back of the neck and clean up the back of the joint after glueing. There's a video of it on the Taylor website. Hard to explain past that, but it all makes sense once you see the thing. Amazing how many neck blanks they can process with the thing in a day.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

The resin and hardener of West System are close enough in density that
5:1 ratio works equally well by weight or volume. I use a few graduated
syringes for small quantities (a few cc's) or a triple beam balance for
larger ones.

As to the preshaping before glueing, a good example is when you cut any
hardwood board on a table saw. When the board is split it the two lengths
will almost inevitably curve inward or away when released from internal
stresses in the board. Though removal of a smaller amount of wood from
the back of a roughed out neck blank will certainly be less, it is still there.

Another good analogy is in the first Machinist's Bedside Reader, where a
machinist demonstrates the catastrophe of trying to true a straight edge
by machining only one side of a rolled steel bar. It of course springs in to
a nice smooth curve immediately upon being released from the vise. If
you don't have any of these books, they are a collection I believe every
machinist or woodworker should have.

_________________
Eschew obfuscation, espouse elucidation.

Hesh buddy, I'm having a hard time figuring out what the slot to the side does!

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

I checked out the roto-shaper, and it's really not shaping the necks, it's pre-shaping them. Fairly standard high production woodworking stuff, and it's a great way to hog off a lot of material very quickly with large diameter spiral cutter heads that get the blanks close enough so the CNC machining centers have much less work to do. Still the final shape and contour is done with ball end bits on a CNC machine which can run at much higher feed rates with the pre-shaped blanks from the roto-shaper.

Do a Google search for "automatic wood shaper" or check e-Bay for them. You'll see some major pieces of gear used in the furniture industry that are similar to what Taylor is using. They have a similar machine down at Fender for hogging out Strat body blanks.

Here's one for you...

http://cgi.ebay.com/RYE-AUTOMATIC-ROTARY-SHAPER-R60E-USED_W0 QQitemZ2558069487QQihZ010QQcategoryZ11810QQrdZ1QQssPageNameZ WD1VQQcmdZViewItem

[QUOTE=Billy T] Hesh buddy, I'm having a hard time figuring out what the slot to the side does![/QUOTE]

Don't know for sure Billy but I suspect that the rebate is to allow clearance for the head of an indexing pin you may choose to put through the 14th fret slot.

cheers

Kim

Well there ya go, just re read Hesh's initial post and he explains that the slots are to allow for locating pins at the 1st and 13th fret slot. Amazing what you can see when you review something. always seems to be something revealed that you should have picked up first time round.

Cheers

Kim

[QUOTE=Rick Turner] I checked out the roto-shaper, and it's really not shaping the necks, it's pre-shaping them...
Still the final shape and contour is done with ball end bits on a CNC machine which can run at much higher feed rates with the pre-shaped blanks from the roto-shaper. [/QUOTE]

I guess I should have implied a bit more knowledge. I cut necks on my Fadal more or less the same way they do. As a general rule, the best way to do efficient production of guitar parts is usually The Taylor Way (TM). I use a rougher neck blank than they do, so there is one extra step in my process. I'm good friends with the guy that put the roto-shaper together.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services