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I had an accident with the bandsaw today, I wasn't hurt but the neck I was working on slipped at the end and cut right into forbidden zone, essentially wrecking all my work to that point.

Talk about frustrated, I'm so mad I had to walk out and decided to not go back in for a while, the one thing I HATE doing the most is cutting out the profile shape of the neck (the headstock and fingerboard taper), it's the one place that I've made the most mistakes. So I'm looking for a better way, CNC would work but there are some pretty big obstacles to overcome there and to be honest I don't have the time to do that right now (Plus I have the CNC doing lots of other things)...

One thing I'm seriously thinking of is using a shaper do to the profiles on the necks, I can cut out the perfect jigs on the CNC and then use those to quickly rough down a neck into the shape I need using three passes (one for the side profile, one for the fingerboard profile and one for the headstock), my goal to get a working blank so I can start carving and final shaping.

So any suggestions? I don't have much floor space left in the shop for a new tool, I do have a router station built into the tablesaw. The problem is that I would have to find a cutter that could cut a necks side profile (that's almost 4.5" of material, that's about a 4" heel at the maximum and at least a 1/2" base for the shape) WITH a bearing, the headstock is the easy part actually and I've already implemented an indexing system into my fingerboard and neck building so securing the neck is not an issue.

Shaper stations aren't cheap but they can handle really large cutters, getting back into building has been tough and I'm out of practice in some areas. It's been a year since I was this active in the shop and I'm feeling it for sure. Today's goof was a stupid one, fortunately it was a practice piece but it made me mad enough to walk out for a while...

Now to find something better...

-Paul-

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-Paul-

Patriot Guitars

Grizzley has the whole setup including the owners neck template shown in their last catalog. I think it takes an expensive and powerful shaper to drive the bit.

Al

Check out Mario's article in the latest issue of "Guitarmaker". It might answer some, if not all of your concerns about neck building.

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

You know my Guitarmaker has not showed... not sure what's up with that just yet...

Argh...

-Paul-

_________________
-Paul-

Patriot Guitars

What's the gist of the article? Doesn't he use a power chain-grinder on necks?

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http://www.presnallguitars.com

Hang tight Paul- I'll get a post together asap on this topic. I've been out of
town and up to my chin the last few weeks, but I've got something to add to
this conversation.
-C

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Freeborn Guitars
and home of BeauGuard©

One thing I should make clear is that when I discuss profile I'm not talking about the round part of the neck, I'm referring to shaping the neck on just two planes. Once I have that right doing the back of the neck and the heel is actualy easy.

I was cutting out the fingerboard taper and coming right up into the headstock when the piece slipped....

Chas I'm looking forward to what you have to say...

Cheers

-Paul-

_________________
-Paul-

Patriot Guitars

Sorry to hear about that Paul, good decision to walk out of the shop and to get back to it when the dust settles down.

Good luck friend!Serge Poirier39000.0246064815

I get a funny feeling in my stomach when someone mentions shapers.
Years ago I made raised panel doors for the cabinet makers in the area. I
had a 3 hp, 1" Powermatic spindle shaper for cutting profiles and raising
panels. It has to be the most dangerous tool I have ever used. With 4"
diameter cutters turning at 10,000 rpm, I was never comfortable using it.
If you go this route, make sure your jigs and fixtures are anchored well
and avoid any free-moving fixtures, if you can (the ones you use with rub
bearings). If you think a big table saw can kick back, you haven't seen
anything until you see what a shaper can do. Maybe just a simple fixture
for the band saw is a good intermediate step. Just MHO.
Craig S.

Craig I feel the same way actually, it's one reason I've avoided this for so long. But to be honest there are no 'Safe' tools in the shop, I had a simple accident and it could have been much worse, the bandsaw is just as dangerous as any other tool I have.

I know how and why it happened, how to prevent it is another story. Todd is correct, if your piece is not solid on the table for the bandsaw it will get slammed down. In the past I have used various hold down jigs to accomplish this one task, but none have ever worked like I really wanted so I'm looking for a better way.

I have a couple of concerns about the shapers I've seen so far, none of them seem to have dust collection which I'm a little surprised at, I'm not sure where I would put one either. The cutters alone are over $200 so that's another thing that I have to take into account, the CNC will do it but only after a good deal of trial and error, I think making shaper sleds would be much simpler.

-Paul-

_________________
-Paul-

Patriot Guitars

there is also the duplicarver option. of course it necessitates having pattern necks available to dublicate. i am in the process of going that route. the need to eliminate as much stress on my hands as possible dictates i go some form of technology to perform repetitive grunt tasks like hogging out neck blanks. i considered cnc but as i have no experience in it whatsoever found the learning curve to daunting, and the buiding of the duplicarver a more practicable solution.

In his article, Mario shows a very simple hold-down sled fixture for his headstock cuts using a table saw. He also shows a simple method of thicknessing the neck using a Wagner safety planer. On the other hand, I'm scared to death about using that "circular chain saw blade" on an angle cutter method to rough profile the neck radius...for me it's still the slower method of rasps and files for that task. On his heel carving, he again uses a very simple jig using the TR slot as a locater and just carves the profile to his jig.

I always seem to like Mario's methods...they are simple and repeatable. I also hate it when he yells at me for over-thinking an operation that he can do in his sleep.

Paul, I'd hold off buying anything until you get your hands on this article.

Neck building has become my favorite and most relaxing process so far...but that just may be me. Wherever you decide to go, I'm sure you'll make it work for you.

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

I thought I would mention this safety tip. I tend to think the router and
shaper are the most dangerous tool in the shop. A table saw is also
dangerous but not if you get a SawStop - it is absolutely foolish to have
any other table saw because the SawStop can save your finger/arm/etc...
- please check it out if you haven't already.

When working with routers or shapers, it is important to only be hogging
off a small amount of material - I believe it is like 1/4 of the diameter of
the router bit. But regardless, I try to make it so the router is only taking
of just a little bit of wood. Also, I tend to think the stronger the motor,
the less chance for the bit to slow down and cause kickback.

Another hugely important tip for shapers and router tables is to use jigs
that are very heavy. If you have a jig that has a fair amount of mass to it,
you will find that it takes away a lot of the danger involved with working
with these two tools.

Just thought I would share some things I have learned over the years

--
Simon

Michael, where can I find out more info on a duplicarver? Any pics or etc would be great!

[QUOTE=csullivan] With 4"
diameter cutters turning at 10,000 rpm...[/QUOTE]
That's just at the spindle, Craig. The cutting edges of that bit are spinning at about a third of the speed of light (or might as well be...).

Good Stuff Terry...

I can do headstock angle and the basic cutout with no problem, your third picture is where I hosed it up ..

I got my guitarmaker today (talk about perfect timing) and will read through Mario's article again tonight, but on the first pass it gives me some new ideas. I have a jig to cut the headstock angle on the tablesaw, but I *always* go back over it with a good sharp handplane to mkae sure it's %100 square and flat.

I'm switching to inserts for my bolt on neck so Marios jig to cut the cheeks using those holes is spot on with what I want to do. I'm going to start laying out stuff tomorrow to get this rolling, I have a whole bunch of new ideas now, I'll use the CNC to make the precision parts. I've also been looking at the Micro-Plane shaper as an alternative tool to a shaper or the router table.

I'll post a full set of pictures once I get it all worked out, I have some spare neck blanks that I'll use to test it on...

Thanks

-Paul-

_________________
-Paul-

Patriot Guitars

These look like a relatively safer and less expensive way of doing this Paul. I bet you'd have to stop and clear it out quite often though.

Howbout a jig the references the truss rod slot, and use the micro-plane shaper to shape the side profile? Something like Terry's but with the neck flipped onto the face.Rod True39001.056724537

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Okay, here's my 2 cents, if a bit tardy....
First a bit of background on shapers.
A true pattern shaper used for making (usually curved) parts from
patterns has two spindles. One rotates CW and the other CCW. Since you
can stack the cutters on the spindle facing either way the cutters are
interchangable. You use whichever rotation is going "downhill" to the
grain. Another advantage to a shaper is you can stack any combinations
of profiles you wish making multiple profile cuts in a single pass. Twin
spindle shapers are generally massive machines and have largely been
rendered obsolete by NC routers. Mass is a plus when making shaper and
router jigs. The heavier they are the less they tend to bounce around.

The typical single spindle shaper is generally intended for running
straight profiles against a fence (moulding,etc.) or doing pattern work
where you can flip the part over to get the "downhill" grain orientation
(not a guitar neck). Cutting "uphill" to the grain runs the risk of the cutter
catching the end grain and splitting off pieces in a usually unintended
way. I suppose one could do half the part with it set CCW, then flip the
cutters and do the other half in CW mode, but that seems way too tedious
for me.

This is a pre-CNC Martin D-18 kit neck from the late '70"s. I never got
around to putting the kit together, but have used it as an example to
follow on my first few guitars. By studying it carefully you can tell by the
tool marks what types of cutters and the sequence they used to make it.
A local luthier and friend visited the Martin factory in those days and saw
how they did them. Apparently it was a jig that had 3 reference faces. 1
for the face of the neck (where the fb goes on) then it tipped up to profile
the headstock and then it stood up on it's end to shape the heel. I'm not
sure if the dovetail was done before or after the shaper work.



Here's my old gal: bought her new back in the early-mid 80"s (in the
Rockwell years) It is 2 speed (7 & 10k) and is reversable.

This is a 2-1/2" cutting height carbide spiral cutter with a flush trim type
bottom bearing on it. You can see the power feed in the background I
use for running mouldings, etc This cutter happens to be CW rotation
(opposite of a router) so the feed direction is left to right Because it's a
spiral it can't really be turned over or it won't be in a down shear
orientation:

Here is an assortment of cutters including straight cutters, round over
(usable for profiling neck shapes, etc. There is also an empty spindle
there too This shaper has removable spindles that come in both 1/2" and
3/4" diameters. You can pretty much assemble any series of profiles that
will fit on the spindle.

Here is a jig for cutting a rear leg of a chair that is pretty much identical
to the "robosand" set up Terken uses. The major difference is that the
dimeter of the cutter does not change the way the sanding sleeve will as
it wears. Granted it's only a few thousands, but accurate is accurate.




Here is my router table set up showing a very similar spiral cutter on a
shaper type spindle that fits into a 1/2" router. The spiral cutter is also a
2-1/2" cut height unit. This one was made by Paso Robles Carbide
( http://bitsnblades.com/prc/prc06.htm ) I use the big PC variable speed
unit in a incra type lift. With the router slowed down I can use many if not
all of my shaper cutters on this type of spindle. Since the big shaper runs
in the reverse rotation I can use both the shaper and the router in the
same way one would use a twin spindle shaper.


For the part time luthier, a 2+ hp router table is plenty of machine. The
only drawback is the non-reversable rotation issue. You can work around
this with slow feed rates, and careful handling.
As for the bandsaw issues, there's no getting around them except for
using the right type of sharp blade and paying attention. Even using a big
shaper or router I bandsaw the blank to within 1/8" of it's finished shape
before running it on the shaper or router table.
Hope this helps.
-CChas Freeborn39007.0255439815

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Freeborn Guitars
and home of BeauGuard©

   Thanks guys for the insight. I am attempting to carve a neck on my second guitar here and am pretty lost. I have a Delta shop master planer/shaper and am not sure what horsepower it is off hand. Looks like I might be able to use it but will definitely have to research what jigs to make or bits to buy. I appreciate the picures too. Right now my neck looks like something I chopped out with a meat cleaver. One thing I'm curious about is how exactly do you hold a shaper jig as you run it through.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

Nick,
The jig or pattern usually cuts one profile or shape at a time and extends
out far enough to hold onto. Terken's photos show this well.
I usually use destaco toggle clamps on mine and hang onto them when I'm
running it through the machine.
I'm not familiar with the Delta shopmaster, so I can't say if it's appropriate
for neck making.
-C

_________________
Freeborn Guitars
and home of BeauGuard©

I have used microplane shapers free hand to shape a neck
I used it to get close to the shape I wanted and finished up with a boggs spoke shave and files it was very fast and easy to control.I did not have any problems with them clogging up.I ajusted the sprrd to were it was comfortable,not too fast.

Paul, I'm not sure I understand the question, but your reference to Terry's third photo helps. Do you glue the board on before you cut the taper on the neck? I do, and it gives me the reference I need to cut the neck with a spokeshave and a rasp. A spokeshave takes off so much wood so quickly, that I can't see any advantage to using a power tool for this. Actually, I've had to learn the hard way to go to the rasp sooner, before I cut into the side of the fretboard with the spokeshave. Power tools don't always have an advantage.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks.

_________________
"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.