Thinking Of Building A Neck Jig, Have A Couple Questions

[Mind Riot]

Hi all. I'm considering building a neck jig to work on guitars. I've been doing fret levels for a bit less than a year now, and thus far I've done about a dozen of them, just on my own guitars and a few friends'. They seem to be turning out pretty well, but I haven't been able to get things really super low and clean when it comes to the action.

I've done the levels a few different ways. First I used radius blocks. Then I used some flat steel stock with sandpaper, following the center line and maintaining the radius. Recently I tried leveling compound, following the string paths, using the steel. All of them have turned out at least decent, but I've noticed a few disturbing things.

For instance, on the neck I leveled compound I checked everything out with my Stew Mac straightedge in each string path. Everything read perfectly flat once I was done from the first fret to the twelfth in each string path, then it also read flat from the twelfth to the end of the board following the slope of the fallaway I put into it. Looked dandy, and I recrowned and polished and strung it up.

But then when I was setting the guitar up and setting the action, I couldn't get it quite as low as I was hoping (specifically, I can't get it below 3/64" on the high E at the twelfth fret without buzzing in the upper register). I looked at it closely, and using both my straightedge and the string itself as a straightedge it appears that when the neck is under tension it develops a slight dip in the 13th to 17th fret region, right next to the neck pocket. We're only talking about thousandths here, but it's enough to hinder my setup efforts.

From everything I've read, this sounds like just the sort of thing the neck jig was designed to overcome.

So I started thinking about how I could go about building one. I have the Guitar Player Repair Guide, and I have looked at Stew Mac at their pictures and diagrams, and I think I understand how the thing works pretty well. So I'm just going to run my idea by you folks, and I would greatly appreciate it if you would tell me if I'm missing something.

I have access to some scrap steel and bolts and such, so the first design variation is that the central spine of the jig would be a length of rectangular steel bar stock. This would have thick enough sides to keep things stiff, and all else being equal should be stronger than the wood version.

For the neck support rods, I was planning on using some long bolts or threaded rod and drilling and cutting threads into the steel spine, so that the neck support rods would be threaded into it and could be raised and lowered by turning them through the threads. The steel would have about 1/8" thick walls and the threads should be able to take well over a hundred pounds of pressure, which seems like way more than anything neck work would impose. Of course, the bolts would have either rubberized cork or plastic tops on them to protect the neck.

I have a turnbuckle that I will be modifying to become a headstock jack, and it will again have protective cork or plastic on the end that comes in contact with the guitar. I would buy a strap and cut two slots in the sides of the steel spine to run it through, and have the strap be able to be tightened to hold the headstock down.

The body platform would be plywood just like the norm, and again would have threaded inserts and bolts with cork to support the body, and I would buy a ratchet strap to hold things down.

The only thing is that I wasn't planning on installing or using the dial indicators. The original neck jig didn't seem to have them, and I'll be checking the neck for straightness against my straightedge, both when setting the truss rod straight with the strings on and when using the turnbuckle to force it back into a straight position. I can understand how the dial indicators would make things more precise, but as of now I think I can build this thing for free, using only scrap parts I have available in the shop (save the straps).

Am I correct in assuming that if I got the neck perfectly straight under string tension, then removed the strings and forced the neck back perfectly straight with the turnbuckle and strap, then supported it with the rods that this would essentially be the function of the neck jig? Am I missing something, and the dial indicators are really essential?

Basically, I just want to know if my design is sound (assuming the rods are positioned well and all that sort of thing) or if there's something fundamental I'm missing here.

I appreciate any thoughts or help you all can give me!

[soapbarstrat]

How big around is the steel rectangle ?

I used a version without the dial indicators for many years and have to say the end result was pretty much as good as I get with the more current version with the indicators. But the indicators are so damn cheap, I consider it to be more of a hassle not to use them. They make setting the pins against the back of the neck go much faster.

I wouldn't like the pins being threaded. I need to them to be able to get the hell out of my way fast, if I'm clamping frets, etc.

Don't be afraid to come up with your own variation of this type of jig. The StewMac jig was designed partly to be a profitable tool for StewMac to sell. Some guys get too hung up on trying to copy it exactly.

Also, when I use the jig, I don't add more "fall away", and I seem to get 12th fret action lower than most.

You could also experiment with the 'Turner Levelers' which level frets with the strings left in place. But I think it would be a real PITA to level the fret-board wood surface that way. And that's where the real leveling should be, if you want to keep your fret top recrowning work to a minimum.

[Mind Riot]

The steel I have in the shop is 1" by 1", with about 1/8" thick sides. I was either going to stack and weld two sections of it together in the spots where the rods would be so there would be more height adjustment space, or buy some 1" by 2" stock.

I may be doing refrets in the future (perhaps sooner than I think) but at the moment I'm still just leveling the frets on mine and my friends guitars.

This already has a lot of differences from the Stew Mac jig, I'm pretty much trying to make it as simple as possible with what I have on hand.

I don't think I've heard of the Turner Levelers. I'll look them up and see what I can find, or if you have a link that would be great too.

I think the basic idea of the neck jig's function is pretty clear to me, so I'll just be working out the little things to make sure everything lines up and fits right and has enough room to adjust and all that detail stuff. Unless there's something big I'm missing.

[soapbarstrat]

The small sized steel tube sounds like you checked out this neck-jig version :

http://www.stewmac.com/tradesecrets/toolti...ts27miller.html

The "turner levelers" are mentioned in a recent thread :

http://projectguitar.ibforums.com/index.php?showtopic=31793

Turner Levelers = Aluminum angle with sandpaper stuck to it.

[Mind Riot]

I actually hadn't seen that jig before, but it seems like a neat idea. I was just thinking of using the steel because I had some scrap laying around that might work but I didn't have any acceptable piece of wood to use, so I would have to buy it if I wanted a wood version. It also seemed a little simpler to just drill and cut threads into the steel for the support rods than it would be to worry about threaded inserts and whatnot. Again, just trying to see if I can engineer it in my head in a way that might work with what I already have.

So does it sound like this would work? I can't really think of anything about it that wouldn't, unless the steel stock bent a bit under the pressure (which I doubt) but even then the support rods could just be adjusted back and forth with the headstock jack until it all read straight.

Thank you very much for the links, the Turner Levelers seem like a really good idea and I may just have some steel or aluminum angle iron laying around I could brutally force to become tools. I could even true them up against my other steel stock levelers that are already flat, using some metal cutting sandpaper and elbow grease.

I think I just may retire to the shop now and see what I can see. I'll definitely check back later, this site just rules for finding out stuff like this. Thanks!

[soapbarstrat]

Using steel for a beam sounds good to me, especially if you can bolt or weld multiple pieces together. Don't tell me you TIG weld, or I'll get jealous.

And be careful not to leave the engineering cap on too long. Sometimes engineers do nothing but ruin a perfectly good thing.

[thegarehanman]

Soapbar, if you take another pop at engineers, I swear on my favorite pair of pants that I will come down to your house and add 1000 overpriced, poorly made, easily broken components to each and every appliance in your house!

Some engineers mess things up, but that seems to be isolated to the really dumb ones and the ones who use the left side of their brain exclusively. The more artistic of us just sprinkle the world with wonderful gadgets, doodads, and turbomachinery.

I think the stewmac jig is a pretty good design, tbh. If I were making one from scratch, I might change a few things, most notably going from a wooden spine to...well, anything other than wood.

[soapbarstrat]

An Engineer being able to find somebody's house ????

[thegarehanman]

We find things just fine. Engineers design laser guided missiles, after all. Well, that's only partially true...civil engineers only build the targets.

Edited August 28, 2007 by thegarehanman

[soapbarstrat]

Always willing to help out an Engineer in need : Google maps shows my house being down the street from where it actually is.

[thegarehanman]

You should have told me sooner! I went to that house and when I saw a Geo Metro in the driveway, I figured someone had probably already gotten to your appliances too!

PS

Let's just hope they're using something a little more refined than google maps to guide missiles.

Edited August 28, 2007 by thegarehanman

[MiKro]

>snip<

PS

Let's just hope they're using something a little more refined than google maps to guide missiles.

Russ, you could've mentioned GPS with a Capital Geee! that's really close LMAO!!!!!!!!!!!!!!!!!!!!!! You know those engineers, they take there numerics to the inth degree!!!!!!

Peace my friend,

Mike

[GregP]

Off Topic:

I took an Engineering theory elective... nothing hands on, just an overview of the profession, it's relevance in the modern world, and relevant topics such as ethics and economy. What the professor helped me understand is that engineers ideally look for the simplest and most efficient solution to a problem, NOT the most technological. There was a good example, that I don't remember too well, but I'll give it a shot-->

Relief was being provided to a village in a desert area somewhere in Africa; I don't recall which country. The main part of the relief were bags of grain, which were presumed to have a good shelf life. However, as it turns out, something (dunno what...memory's off) was making the food go bad by the time it was consumed, and the whole effort was too wasteful. The solution: refrigeration!

Team 1 comes in, creates what amounts to a giant refrigerator for grain and other perishables to be stored. Success! Well, no. Power was spotty and could be out for weeks at a time. In the meantime, the metal "fridge" structure exacerbated the problem as it heated up with the sun, and the grain was worse off than ever. The designers had "P.Eng" in their titles, but engineers they were not.

Team 2 comes in, and finds out what the locals do and what the local resources are. As it turns out, they have this technique of more or less "burying" certain perishables, but it wasn't typically used on the scale of these grain deliveries. Team 2 creates a much larger version of this... cellar... (for lack of a better word) which kept everything cool enough, and was completely passive... no electricity needed. Also, it cost less to build and maintain. That's engineering.

--

Point being, to me, if it's not the simplest (or at least most effective) solution to a problem, it's not engineering... it's technology. Made by technologists, not engineers.

Mind you... not being an engineer, I'm sure a P.Eng would beat me senseless with that ring of his for suggesting that he's not an Engineer. LOL!

Greg

[thegarehanman]

Right on, greg. The best design engineers out there realize that the best design is also the simplest, if for no other reasons than it's likely cheaper to make, less likely to break, and easier to operate (with aesthetics, simplicity goes out the window, because otherwise my recent gotm submission would indicate that i'm an awful engineer ). Of course, there are tons of other considerations depending on the project, but that's not the point. The ones who can't design well either check gauges at plants or just get a phd and study materials or tribology or something "fun" like that.

So yeah, neck jigs.

Edited August 28, 2007 by thegarehanman

[Mind Riot]

Using steel for a beam sounds good to me, especially if you can bolt or weld multiple pieces together. Don't tell me you TIG weld, or I'll get jealous.

I actually don't weld at all, my father offered to help me out with that. He's quite the knowledgeable and handy old gentleman. Every time I come up with some crazy scheme for building something instead of buying it I'll usually ask him for a consult on the design, to see if he notices anything that could be done better. He sometimes sees a simpler way of doing things that I might have overthought.

Between my DIY electronic drum set, my acoustic panels, and a bunch of other guitar or music related projects I'm always annoying the wife with something.

[SwedishLuthier]

About the idea for threaded support pins: Its pretty much the same way my jig is made. Works fine and I find it much more straight forward compared to the way Dan does it in the SM video. And I don't fret in the jig, so thats not an issue for me, thou I see your point soapbar. If I was doing that (fretting in the jig) the threaded support pins might have to be re-thought.

And as Soapbar says: use the dials. It really speed up the setup time.

Now I consider to try the Turner method (leveling with strings on) as I think it is much simpler and of cause is much closer to what we try to emulate with the neck jig (string tension). Simple, as in less engineering time. I spent a lot of time perfecting my jig. Too much time. I used to be an engineer...

[brewu22]

Using steel for a beam sounds good to me, especially if you can bolt or weld multiple pieces together. Don't tell me you TIG weld, or I'll get jealous.

And be careful not to leave the engineering cap on too long. Sometimes engineers do nothing but ruin a perfectly good thing.

hehe I can TIG, MIG, and stick, but now have no access to those tools. +1 to engineers, gotta watch em. Screw up a one cow cattle drive.

[Mind Riot]

Well, I went and made some of the Turner Levelers, as well as a surrogate nut to give the strings a bit more clearance since the angle steel I was using is pretty thick. I took pictures and wrote up my experiences and posted the thread over on the HC Electric Guitar forum, so rather than typing the whole thing up again here I thought I'd just post a link so everybody can see it.

http://acapella.harmony-central.com/forums...d.php?t=1730105

It worked pretty darn well actually. Mr. Turner's on to something, methinks.

I'm still planning on building a neck jig and getting into refrets and such, and bought a five foot length of thick walled 1 1/2" by 2 1/2" rectangular steel stock to use for the spine. But this fret leveling method really seems to work pretty well, and all it cost me was a dollar in smaller steel for the surrogate nut (I didn't have any of the smaller angle steel) and a little time in the shop cutting the scrap steel and cleaning it up and making sure it was flat for the levelers.

Edited August 30, 2007 by Mind Riot

[soapbarstrat]

...and bought a five foot length of thick walled 1 1/2" by 2 1/2" rectangular steel stock to use for the spine.

That's big enough around that you can make a solid "jig block" out of wood, aluminum, MDF, etc, and bolt it inside the hollow steel tube.

[Mind Riot]

I might be being thick, but why would I want to do that?

Oh, and what did you all think of the fret job?

[SwedishLuthier]

Nice tutorial Mind Riot. Any chance of putting it up here for future reference?

Inspired by this thread (and the one at the OLF, and Mattia nagging about how good the method is, and…) I decided to try it. I had the perfect candidate for this test. I got a typical entry level classical in. It had (of cause) no truss rod and a bump in the neck in the heal neck area (a problem as classical as the guitar). It was a too cheap instrument to do a “proper” job (jig it up in the neck jig, pull the frets, level the fretboard under tension, refret and level the frets. So to save the customer some money and get a playable instrument I decided to try the Turner method. It took me about an hour to cut up some different lengths of L-shaped aluminium beam, grind off all sharp edges, true them up with 400 grit wet’n’dry on the band saw cast iron table and polish them really nice.

I didn’t even mask off the fretboard or raised the strings. Rick Turner mentioned in his comments on OLF that he leaves the string in the nut. I just carefully marked the tops with a pen and sanded away. When the frets were level I remover the strings, masked the fretboard and crowned the frets. It took me maybe a full hour to do the complete job, and I did it this way for the first time and it had a serious bump in the neck. I’d say that with a little routine (and an adjustable trussrod) I would be able to do it in maybe 30-40 minutes. If the next couple of fret jobs come out as clean and nice as this one this method will be a real timesaver (and moneymaker).

One more proof on how good this forum is. Cheers to ya all.

[soapbarstrat]

I might be being thick, but why would I want to do that?

I meant if you wanted to use sliding rods along with thumbscrews, bushings, etc, you could make a small solid beam for just the rods. Could even be made of a few sections of scrap wood.

That's pretty much how I've already planned to make my next one, since I have a 4x4 hollow metal tube.

[Mind Riot]

Ah, okay, that makes sense.

Well, I don't know when I'll get around to building this thing, but I'm not very good at waiting when I've got the parts and I'm excited about the project so it probably won't be very long.

I spent a little more time with the guitar I leveled using the Turner levelers last night doing some more setup work, and it's now setup with the lowest, smoothest action I have thus far been able to achieve on any of the guitars I've leveled. High E can be set at about 2.5/64" without buzzing, but you can't quite get a whole step bend out of it on the high frets without it choking (it's a 9.5" radius, and with the conical leveling, it flattens out to about a 12" at the body end). I set it up at 3/64" on the high E, with the B and G the same and all the wound strings at 4/64". I can get most of them lower, but this feels comfortable when I dig in and spank it hard. I'm very pleased, and I think I'll definitely be leveling frets this way again.

Edited August 30, 2007 by Mind Riot

[soapbarstrat]

I pretty much now have it thought out in my mind, how to pull some frets where there's a hump in the board, "simulate the fret tangs", tune to pitch, level out the hump with Turner leveler, replace frets, then level frets with Turner Levelers. All the while the guitar is in the playing position, mounted in my set-up jig.

[Woodenspoke]

I pretty much now have it thought out in my mind, how to pull some frets where there's a hump in the board, "simulate the fret tangs", tune to pitch, level out the hump with Turner leveler, replace frets, then level frets with Turner Levelers. All the while the guitar is in the playing position, mounted in my set-up jig.

Dont believe him he uses mind control to make his customers believe the necks perfect when he is finished. Actually he is a fanatical neck crazed repair man and wont even sleep until its right, I still say it's mind control, since no one can do such good work. LOL