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Howdy. I have the resources to pay a good luthier to do my setups, but it's about time I buckle down and start to figure this out. I own a collection of about 15 guitars, and growing, so necessity is also the mother of invention.

Here's the situation. I own an Epiphone Masterbilt AJ-500M (an acoustic slope dread) that I love. I bought a second one cheap on CL to practice setups on. Part of the reason it was cheap was because it come w/o the original nut, saddle or bridge pins.

I ordered replacement parts in TUSQ that seem to match up pretty well. The nut was already preslotted (not that it doesn't need work, but it didn't come as a blank).

After I put the new parts in, I strung up the guitar with light gauge D'Addarios. Starting at about the 3rd fret all the way to about the 17th, every string bottomed out. I adjusted the truss rod counter-clockwise (loosened it) little by little to a total of about a half-turn, which helped somewhat. At this point, though, the truss rod nut froze and would loosen no more. I wisely stopped trying and did not force it to turn any further.

Sighting down the neck, there is a considerable bow (valley) between the first fret down to about the 12th, at which point the strings once again bottom out. There is a noticeable "hump" in the neck right around the area where the neck joins the body.

Any thoughts?

BTW, I am not going into battle unarmed. I just received the newest edition of Dan Erlewine's Guitar Player Repair Guide and also have purchased his three vids covering setups, truss rods, etc. I'm willing to make the investment as I go forward.

I confess that I'm learning as I go, but that's why I bought this guitar: to make mistakes on it and learn from the experience.

Thank you in advance for your insights.

To start I would readjust the truss rod to get the fingerboard flat as you can, with the strings up to pitch. What is the height of the saddle over the bridge? How much room do you have over the first fret and what is the height of the strings at the 12th fret? Bottoming out? Once you check that you will have an idea of what the geometry of the guitar is. You can go from there. Most likely you will find you need a neck reset to get it back in the ball park. If that is the case it might not be the best guitar to practice setup on. But then if you were to learn how to do a neck reset it would be a big plus tending to those 15 guitars!!!

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Joe Beaver
Maker of Sawdust

Joe, thanks. Yes, I think the neck might be a lost cause, but not sure yet. However, I think I may have sanded the down the height of the new saddle too much. At it's highest point it is only about 1/8" high (in the center) and even less on the two ends. Should I go ahead and order a couple more saddle blanks? I had modeled it on the identical saddle from the identical model guitar I own.

And what do you think is causing the trussrod nut to freeze up? Is this just perhaps lubrication, or stripped threads? I'm afraid to force it before I get more information.

I should mention that I have above-average mechanical aptitude, and that's why I walked away from the truss rod when it froze. To quote John Prine, for more than 40 years I've "busted my knuckles on a monkey wrench" by working on many cars. I still do brake jobs and routine maintenance, although I leave timing belts and head gaskets and such for my mechanic.

I'ts getting late, but I'll try to check back one more time before hitting the sack.

Thanks, Joe. What do you think the deal is with the truss rod?

I wouldn't worry about the truss rod ... you say the neck has an excessive up-bow (concave) so the fact that the nut jams when loosening is neither here nor there ... you are going to want to tighten it, not loosen it any further.

Now, if it jams when tightening, (before you have the fretboard straight) then you do have a problem ... but by no means an insoluble one.

Hey Scott

Set-up can be done lots of ways but here's what works for me and works very, very well too. Before today is over I will likely do this five or more times....

I was always looking for a proper sequence of events or a method in a sequential order and indeed there is a method that has a sequential order where we eliminate variables as we work making it all come together in the end with a very good if not perfect within the limitations of the specific instrument set-up.

1) Take the nut out of play by doing the nut slots first. That is after adjusting the truss rod. What you want to see is a little bit of relief (forward bow) on the treble side and hopefully more relief on the bass side. This is determined by sighting down the two respective edges of the fret board and adjusting the truss rod with strings on, the strings you plan on using, and tuned to pitch. More on relief later...

2) Once the rod is adjusted for minimal relief on the treble side and more relief on the bass side the nut slots are cut. You can use nut files, needle files, a chain saw, or a tactical nuclear weapon, makes no difference to me...

But first....... a word about necks and truss rods. Ideally we want to have a neck that when under tension has more relief on the bass side and less on the treble side. What we often have though is the reverse or the same amount of relief on both sides. This is a function of how well..... or not.... the instrument was built/crafted. If a fret dress or refret is not going to be done which can correct relief as we wish we have to work with what we have. Such is life eh....

3) With the nut slots cut, and I can tell you how to cut them if you want to know just ask, and the rod adjusted for the best relief that this ax will bear with the guitar in the playing position in your lap measure the action at the 12th fret measured in 64th of an inch so that we both are speaking the same language.

For a dr*ad sized guitar with 12's on it you ideally want to see 4/64th" for the high e at the 12th and 6/64th" for the low e at the 12th.

What ever you do see write it down and proceed to step 4.

4) After recording the current action, having adjusted the rod, cut the nut slots, etc. this is where we adjust the action with the saddle. Is this starting to make sense, rod first, then nut slots and now we are moving to the saddle? See the sequential nature in the approach eliminating variables such as the rod and nut slots early on and then only addressing what's left. I'm keen to flow chart how I do set-up and post it one of these days.

So let's say we have 3/64th" for the high e at the 12th the action needs to come up. Likewise if it was 6/64th" for the high e the action needs to come down to 4/64th".

What ever we do at the saddles is the sum of two times what we want to add or subtract at the 12th. More specifically if we want to raise action at the 12th 1/64" we need to raise the saddle 2/64th" or 1/32nd because the 12th is half way to the saddle and the nut slots remain fixed because we already did them and took them out of play.

I losen the strings and capo at the 2nd and pull the pins for the low e, a, and d and remove the saddle. If the saddle has to come down remove the amount of material as in the example above from the saddle bottom. If it needs to come up make a new saddle or shim the sucker.

5) Adjusting the saddle up or down as need be on the bass and treble side take it to the spec of 4 and 6/64th respectively. If you are into 13's use 5 and 7 respectively. These are Martin numbers by the way and many pro shops use them because they are great numbers.

Install saddle, tune to pitch, take measurements again and repeat as needed or when you can get to the target of 4 and 6 with 12's or 5 and 7 with 13's it's done.

Five steps to a good set-up.

NOTE: We won't and don't use pre-made nuts because they never fit right, limit your options on string spacing, and require extensive fitting and work to get them right making the crafting of a new bone nut from scratch really no more work and it also provides a better value to the client since a bone nut is an upgrade.

The hump you say.... this is what happens when boards are fretted off the neck, glued to the neck and called good. If the instrument had the neck installed prior to fretting the fret board could have been milled level and the hump eliminated.

There are a couple of things that separate the better builders from the novices and one of them is the absence of the body hump.

Let me know if this makes sense to you and feel free to PM as well.

I found Kent Everett's DVD quite helpful.

http://www.apprenticepublishing.com/adjusting.htm

Basically, everything Hesh said, but demonstrated for you.

Steve

Geez, Hesh, you're also so generous with your time. This is really wonderful.

A basic question: for measuring those distances, can I use a set of feeler gauges, or will I be wanting to invest in a caliper?

Thanks, Steve. I have a set of three Dan Erlewine DVDs that I haven't watched yet. These cover setup and all the basics. Is the Kent Everett vid better in this regard? I don't mind spending the extra $$$ if it will help.

Thanks!

It makes sense to me that more relief on the bass side would be beneficial, but this is the first I've read that a guitar can be intentionally built with more relief on the bass side. How is that done?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I don't disbelieve Hesh, but yeah, I'm kinda interested in how this is done as well.

Hey Scott: Taking a break here in between repairs. The next one for me today is a nice PRS that the owner likes to be tuned in C.....

OK all you need to measure action is a 6" engineer's scale (ruler) with 1/64th" graduations. For me I need the engineer's scale and a good set of glasses....

Great question J about building in more relief on the bass side.

It all starts with........ you guessed it..... my previous irritable bowel syndrome rants against fretting the board off the neck.

When you fret the guitar or any fretted instrument after the board is installed and the neck is installed you have complete control over the level(s) of relief on either side of the neck.

More specifically once the board is on the neck, neck on the instrument and truss rod adjusted flat and the board is leveled you can mill in additional relief (or remove relief) with the leveling beams simply by applying slight finger pressure to the headstock pressing it back slightly and continuing to use the leveling beam. This makes the middle of the neck rise up ever so slightly permitting concentrated board material to be removed say around the 7th fret.

Like wise pulling the neck down ever so slightly in the middle when leveling will reduce the amout of relief on that respective side of the neck.

Once fretted the same procedure can be repeated if need be to the frets, it only take a minute or two, and gives one complete control over how much relief you have and where on the neck. It also permits different levels of relief on the treble side with less desirable and the bass side with more relief desirable.

Make sense? Let me know if you have any questions this is a pretty easy concept and I am not sure that I explained it as simply as I should have.

Interesting, thanks, Hesh. This is one of those deals that would probably make a lot more sense to witness it being done in person.

BTW, Hesh, to respond to what you stated in an earlier post: I'm not certain, but I would guess that the fretboard on this guitar was glued on the neck BEFORE adjustments. This particular series of guitars, as far as Chinese guitars go, is prized by a number of players in the sub-$1000 price range. They would be a notch below Eastmans and on par with, say, Yamaha or Blueridge. I've owned one for years, and know many players who own them, and I've never heard of this issue of the "hump" where the neck joins the body. I think this is more likely to two factors:

1) Too much relief via the truss rod
2) I shaved down the saddle too low.

I'm going to order a couple new saddles to experiment with. You said I could use a "shim" underneath to play with heightening the saddle temporarily. Since I'm a new luthier without a chest full of parts, is there something easy to acquire of that I might even have lying around the house that could use as a temporary shim to give this a go?

Thanks, Hesh!

Kindest Regards,
Scott

I see how pressure on the headstock would affect material removal around the seventh fret. but I'm not clear how you bias the removal to the bass side of the fretboard. Do you apply more pressure to the bass side of the leveling tool you are using to remove more from the bass side?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Sure, seeing it being done is way better for the way I learn too and I completely understand.

If you are simply experimenting with shims any repurposed plastic container can make shims. Mind you this is not an ideal material for a final shim but for experimenting with how much shim you need plastic is fine.

Remember 1/32" increase in saddle height will get you 1/64" higher action at the 12th fret.

Also everything in a set-up action wise is a function of the nut slots too. If the slots are too high, and they usually are, action can be lowered at the nut and should be prior to messing with the saddle. That's the sequential nature of the method that I detailed this morning.

For me the very last adjustment that I make on an acoustic instrument is the saddle. First is the truss rod, then the nut slots then the saddle.

You may want to purchase bone saddle blanks and start thinking about making saddles yourself. It's easy, fun, fast and rewarding in so much as you can also correct that always wrong f*ctory intonation as well.

J I owe you an apology because I forgot to add that when doing the finger pressure thing on the head stock you support the neck under the 7thish fret area to be a fulcrum.... Sorry my friend and this may make more sense now.

You asked about pressure with the leveling beam. Step one is observing the neck under string tension and tuned to pitch with the exact kind of strings that will be used in the final set-up. We observe where and how much relief the neck has as is and then record this. This is how we might determine that say the bass side has less relief than the treble side and of course we want to reverse this with our efforts.

If this is the case, less on the bass side and more on the teble side with the neck supported under the 7th pushing back with slight finger pressure, perhaps one pound of pressure is all it takes creates some back bow and then with the leveling beam with normal pressure we simply do some additional passes on the bass side only.... to mill more relief into either the frets if it is fretted or the board if it is not yet fretted. Doing this to the board helps us be able to fret and be very, very close with minimal fret material removal after fretting.

For the treble side say we want to remove relief we simply pull down with one hand under the 7th while taking normal strokes on the treble side only.... with the leveling beam. With this process I can add relief where ever I want it or remove relief where I don't want it. It gives us complete control over the fret plane.

If the board is fretted prior to installation on the neck there will be no opportunity to correct anything without milling away brand new frets..... If there is a body hump it lives on and the frets over that hump may lose much of their height to true up the fret plane.

I had some plans to do a toot on fretting which would include this and I am still keen to do it the next time I have a good opportunity with an ax at hand that the client does not mind me publishing photos of. I am sure you can understand that we protect our clients confidentiality at all times so I always ask if we want to use someone's guitar in a teaching demo.

Anyway the fretting toot would require folks interested to buy or make leveling beams. Murray, our OLF bro sells great leveling beams for a very good price on eBay under the technofret name if anyone wants to start tooling up to learn to do professional fret work. Or you can make your own out of 1 x 2 aluminum bar stock but you will need a calibrated surface plate and one hell of an arm because you can be burnishing these things for hours I tell ya.... When I was an apprentice I had to make my own leveling beams and it sucked....

Lastly in many threads where disagreements break out what is often not discussed is the concept of professional standards. Some folks who breath thier own air and don't mind may have never been exposed to peer scrutiny just like is the case with many occupations. Unfortunately with Lutherie there is nothing stopping someone who just bought a daisy rock guitar from calling themselves a Luthier.

When I teach I teach to professional standards. That's also why proper tools are a no brainer for us and considered very much part of the trade if this is the trade that one wishes to be in.

I understand the attraction to repurpose this and that and we do that too, far more than likely anyone else here.... but ONLY when doing so provides the very best results for our clients - period!

If I am to share something that took me years to learn and something that is someone else's method I need thier buy-in, which I have by the way, and I also need to know that it won't degenerate into an argument because someone else who may not know what the hell they are even talking about interferes with the learning opportunity for others.

If you sense some reluctancy from me to share that will be a historic event and also correct. One does get reluctant when hacks go unchecked promoting unsound methods and one finds themselves banging their head against a wall for trying to be generous..... This is exactly why most pros will not post here by the way.

So with that said I am always happy to help but I am also very keen to call out the hacks if they try to take the opportunities and choices aways from others. Nuff said. In the end who gets hurt is you guys, not me...., but it does hurt me to think that you guys may not have the same opportunities and high level of help that I received here. Actually that is one of my worst nightmares, seriously.... because for some weird-arse reason this stuff is important to me and I want to get it right - always....

Thanks, Hesh, for your usual detailed thorough explanation and for taking the time to write it out. I figure you must be blazing fast on a keyboard so you still have time for the work in the shop. I'm thinking your approach could be particularly good for guitars that get tuned to drop-D, open G, or such to avoid fret rattle on the low E. I think I'll give this a shot on one of my guitars that is a little unhappy with detuned low strings.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Thanks for all the tips, Hesh.

I know I can look this up somewhere, but a question:

Questions: What is the standard clearance on an acoustic guitar at the first fret, sixth string vs first string? I assume this is measured from the top of the fret to the bottom of string, correct? I assume feeler gauges would work for this.

What is your opinion of TUSQ? I've already bought TUSQ nut, saddle and bridge pins for this job. Would prefer to not switch everything out, although I'd certainly be open to buying some good quality bone blanks and fashioning my own saddle. One advantage here is I have the identical guitar model in-house with the original factory components on it (it came from the plant with real bone all the way around), so I can base my copy roughly on the other guitar.

Thoughts?

Will check in later.

Scott

I agree J and one that I did yesterday, a PRS tuned to C.... would have benefitted from having it's fret plane shaped for the low tension AND the fact that this one had as much relief on the bass side as on the treble side.

It's always hard to get someone rattle free, low action with some of these lower tension tunings and in the case of C the intonation adjustments necessary for the low e are outside the range of the adjustment of the PRS. Compromises have to do.

OK Scott your very good question about standard clearance. There is no standard clearance or if you mean a spec to subscribe to.

However what we are speaking of here is how low to cut the nut slots for each respective string. One of the beautiful things about the approach to set-up that I detailed earlier is the sequential nature of the method. I'm a step by step kind of guy and wanted a sequential approach to my set-up work so this idea that step one is a rod adjustment and then step two is the nut slots has made my life way easier.

Each respective string has a different optimal height as measured by fretting and holding the note fretted on each string between the 2nd and third fret. While holding the string fretted observe the distance from the top of the first fret crown and the bottom of the respective string. To get in the ball park of how we do it we will take the high e for example to maybe .001" above the first fret, perhaps less at times... while holding a fretted note between the 2nd fret and the third fret. The height is so very low that I can't even see it.... but I can hear it because as I press the string over the first fret while holding between the second fret and third if I hear a "tink" there is still a gap ever so slight as it is.

As the diameter of the string increases so too will this distance. So the b will be just a touch higher, maybe .002". For the rest I tend to cut to the level of the space being around half the diameter of the respective string. So you can see that by the time I get to the low e with 12's on the instrument the space increases to around half the diameter of that string or .026".

This is way lower than most folks will set-up an instrument because for the high e and b we are at the level where one stroke too far with the nut file and you just blew it all and have to do a new nut or fill the existing one.

The feel of a guitar set-up this way is incredible by the way and we hear folks raving every time they experience this picking up their guitar and trying it out in front of us.

I'll add the higher the nut slots when they don't need to be that high the more intonation issues the instrument may have because to fret in the first several positions requires the string to stretch way more. If it occurred to you that any benefit from a compensated nut is also negated you win the prize because that's correct too.

In our experience the vast majority of intonations issues that are not the result of the string being the wrong length can be eliminated simply by cutting the nut slots well.

F*ctories don't cut nut slots well mostly because it requires skilled labor, skilled labor costs more.... and there is additional risk in that one swipe too far with the nut slot file and it's new nut time on a new instrument.

None of this stuff is difficult mind you but much of it can blow one's mind when they learn that they have been actually struggling with nearly every instrument one has ever played. This realization comes when a guitar is very well set-up and plays like butter, plays in tune everywhere, and will not buzz or rattle either.

It's not uncommon for me to lower the nut slots on say a brand new G*bson 90% on the high strings..... That's how far off they can be. Shame too because folks tend to assume that since the instrument is new it's been set-up - wrong.... These days with Mom and Pop music stores failing all over the country from Internet competition, G*itar C*nter, etc. and not learning how to have a parasitic relationship with the Internet reseller's marketing spend very few new guitars are set-up... It's good for our business but the customers struggle and that's never good.