Neck Jig (stewm) need or nonsense?

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Mario Kessels
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Neck Jig (stewm) need or nonsense?

Post by Mario Kessels »

Dear friends,

I have been leveling and setting up hundreds of guitars over the years and have been thinking about the validity of arguments for the use of the famous neck jig ( dan erlewine) for some years now. I don't use one myself. A friend of mine uses one and once i levelled a fretboard and was not satisfied and let him do it afterwards with no improvement. Of course this does not mean anything but thats my experience with it.
With my engineering background i have issues with the arguments used for the jig.
In short: i dont think it has enough benefits and when i have a problem neck i prefer to work with the strings on so its not a simulation of forces but the forces really at play.
Here are some of my thoughts and i wonder what you guys think, knowing there is quite some users here that really like it. Maybe if your arguments are good i will have to start using one :)
1) a guitar strung up has some relief most of the time. During the setup in the jig the trussrod is tightened to level the fretboard and forces are intoduced. Here is my first problem, the forces now are not the same as during correct string tension and relief.
2) to simulate the straight fretboard under string tension the neck is manipulated. The vectors intoduced here are different than the vectors resulting from string tension.
3) in the end the correct string tension is introduced during setup (1st time during process) and some relief will likely be introduced by releasing the trussrod. Again new forces are introduced here.

So for me it would seem that the simulation is not very realistic and work is still done in a situation where forces and vectors are incorrect.

Therefore i think that In the rare occasion that the tension is needed during leveling frets is better to use a l/u/t profile with strings on.
Very curious about your opinions and really wonder if there is someone with much experience that really has seen significant improvement in setup results using this or simular jig.

Grz Mario
Mark Wybierala
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Re: Neck Jig (stewm) need or nonsense?

Post by Mark Wybierala »

Hey Mario, Many years ago, I looked at the stewmac jig and basically came up with the same conclusions that you have. Its a neat idea but you are correct in that the vectors do not duplicate string tension in an accurate manner. I've read everything that Mr. Erlewine has written. Generally speaking, I can't fault him on any of his processes but the missing book that he has not written is "Guitar Repair for Profit". I have dedicated most of my study over the years on fretwork and continue to do so. There still remains some mystery to the perfect fretboard but I do okay with very satisfied clients. I think that you can take the concept of the neck jig and apply it in a much simpler form. The term "level" is just a relative thing. You can pick up a random guitar that plays rewarding and impressively only to find that there are an abundance of leveling errors that do not matter. On the other hand, you can be given a problem guitar that really doesn't want to be a guitar at all. Its not always a scientific process. I don't think that the neck jig is essential and there are a number of ways to perform a similar process in a more realistic and time efficient manner. Just looking at the neck jig and reading the instructions is enough to inspire useful and practical ideas. I've built my own copy but I never use it.
Michael Lewis
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Re: Neck Jig (stewm) need or nonsense?

Post by Michael Lewis »

As with most of the tools Dan has developed, they work. My feeling is the neck jig is best suited for dealing with flexible necks as often found on electric guitars that use very light strings.
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Barry Daniels
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Re: Neck Jig (stewm) need or nonsense?

Post by Barry Daniels »

Mario, the direction of the vectors is not as important as you may think. Pretty much any vector ends up making the neck bow forward.
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Mario Kessels
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Re: Neck Jig (stewm) need or nonsense?

Post by Mario Kessels »

Does that mean that you think you get results you dont get without the jig? I dont hear any motivation to use it except for maybe the one very problematic guitar that rarely passes by?
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Barry Daniels
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Re: Neck Jig (stewm) need or nonsense?

Post by Barry Daniels »

I made my jig for a problematic neck 30 years ago and have been using it every since just cause I have it. I think it helps me do a slightly better job. Is it necessary? Not really on a normal neck.
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Mark Wybierala
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Re: Neck Jig (stewm) need or nonsense?

Post by Mark Wybierala »

I think that I'll go along with the current mood of this subject. The jig isn't a bad idea. But there are other ways to simulate tension on a neck. If you have one, or something like it, you could easily incorporate it into a practiced, and streamlined developed routine. At any time, you could employ the full capability of it in the manner that it's operation is described. Everyone has their own routine and there would be nothing I would criticize about someone who employed the jig daily. I just went in a different direction. I have had many guitars for which a simulated tension leveling was indicated as the correct process to investigate. But I also have a number of processes available to do this without the jig. If you add this jig to your routine servicing method, I suppose it could also add a level of safety to the guitars you service due to the instrument being fairly well secured avoiding accidents that can occur otherwise. On my bench, the jig is probably necessary for set neck guitars and acoustic guitars if I have a need to thoroughly scrutinize the geometry under tension. In my case however, the majority of my set neck and acoustic guitars from my customer base do not fall into the value range to make this indepth level of scrutiny economically appropriate as a routine. Additionally, the higher value instruments typically do not have as much of a need because of the quality of construction and superior wood employed. This is not to say that I don't work on valuable set neck and acoustic guitars. It is just rare that one would stand out as needing the jig. I draw the line about needing the jig mounted in a rotational vise for the purpose of setting the intonation in a vertical playing position. I believe that when I saw pictures of the vise being used in this manner, I lost interest in the jig -- under the heading of "overkill and gimmick".

I would say, if the jig inspires your intuitive sense of being the right thing to do, get one or build something like it. Guitar servicing that results in mojo should be intuitive with an equal amount of accurate science.
Mario Kessels
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Re: Neck Jig (stewm) need or nonsense?

Post by Mario Kessels »

I completely agree Mark. I do intonate the guitar in playing position btw. but i just hold it...
my conclusion is that using a gig like this for my leveling proces does not bring a lot on a normal guitar but costs a lot ( time thus money).
Thx for the inputs
Gordon Bellerose
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Re: Neck Jig (stewm) need or nonsense?

Post by Gordon Bellerose »

I've only been in the repair business for about 7 yrs now, so obviously some of you guys have more experience.
My experience has been that using a notched straightedge to get the finger board straight, leveling frets while in this position, and setting intonation and action while holding the guitar in the playing position, works for me.

I have never worked on a guitar that does not have a truss rod, and that may be another thing altogether.

Another consideration for a lot of us, is room. How many of us can afford a shop large enough to store all these tools that may only be used periodically?
My thought on the neck jig is that it is VERY expensive for little to no benefit; at least to me.
I need your help. I can't possibly make all the mistakes myself!
David King
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Re: Neck Jig (stewm) need or nonsense?

Post by David King »

I had a very problematic bass neck the other day and I had every confidence that with a few minutes on my home-built neck gig (I've had it for 25 years now) would help but it not so. Every time I put string tension on and tightened up the truss rod the neck had a new hump in a different spot seemingly. Pulling the frets out and sanding these humps down repeatedly made no difference. The fingerboard was simply not hard enough to counteract the truss rod tension.
What helped was tearing off the walnut fingerboard and replacing it with a thicker, acrylic infused macassar ebony board. While I had the board off I went ahead and installed a pair of 1/8" x 1/2" CF spars which I embedded 1/8" up into the new board. For simplicity I decided to fret the board before gluing it back on and then I used a 3/4" x 3" solid aluminum caul to glue the board back on registering off the fret tops. That fixed it. The neck was so stiff that it needed no truss rod tension and the tone and sustain of the instrument was completely transformed for the better. I've since knocked that jig down and put the pieces back in the corner where it had been for the last 10 years. What I've learned is that there is usually an underlying cause for a poorly behaved neck and I would do much better addressing that directly than wasting time trying to fix these types of instruments with short term inadequate solutions.
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