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School me on truss rods!

I really like one piece maple necks, I don't like adjusting the neck at the heel. I do like the side adjuster I've seen on a warmoth neck, but I'm fine with adjusting at the headstock.

All the tutorials I've seen for making a one piece neck use a curved channel, are all truss rod channels curved? I was under the impression that they were flat. This seems unnecessarily complicated, but I assume this is for vintage correctness (which I don't care a whole lot about)?

So what type of truss rod gets the job done best and is easiest to install for a first timer?

Bonus question...
Fender necks seem to be typically flat sawn, but if a person was to use maple that is quarter sawn could a person theoretically forego a truss rod all together?

Get a two way truss rod. Either the style sold by LMI or the Martin. Both are installed in a flat bottom channel you can cut with a router or on the table saw.
You have not been building guitars long enough to construct a neck without one, no offense intended. I know how to construct and service a neck without a truss rod yet I use them on every build.

Steve

There are a variety of different truss rod designs - all work, each has its advantages. Simplest is a hunk of something stiff (steel tubing or tee bar maybe) to stiffen a neck. Martin did this until about 1980.

Gibson, Fender and many others embedded a threaded rod, often but not always curved in the neck such that when you tighten the adjuster the rod goes into tension (just like strings) only on the other side of the neutral axis. While the strings are trying to bend it one way, the truss rod tries to bend it the other way. The neck itself is in compression . Simple, works well, you can route from the front or back but you'll have to build a sled. If you route from the back you'll have a skunk stripe.

The third primary kind of rod consists of two parallel parts - one of them is thread on each end (reverse thread on one end). It is usually put in a flat channel just below the fretboard. When it is tightened the middle part (under the 5th- 8th frets) bows upwards, countering the force of the strings. Double acting rods also can force the middle of the f/b down (actually it is pushing the ends up) - in other words it can introduce back bow or drive the neck flat. This can be advantageous when leveling frets, I don't know any other use for it.

Each kind of truss rod has its preferred method of installation. In general the adjuster can be put at either end, there may be other things that dictate that. Obviously a disadvantage of a Fender neck with the adjuster in the heel is that you have to take the neck off to adjust it. The new Gotoh right angle adjuster has addressed that ( I installed a Warmoth neck that had one, its kind of cool). Headstock adjusters do weaken the head but sometimes are necessary.

Many guitars do not have truss rods - either the necks are built really stiff (maybe carbon fiber rods) or they have low string tension (classicals usually don't but they often have relief planed into the f/b) but I think that is a disservice to both yourself as the builder and someone down the line. Different string gauges will cause different amounts of relief, different players need different amounts of relief.

Read Hiscock chapter 6. If you have been following either my tele or LP build on the tele forum you'll see the double acting truss rod installed in a Fender or Gibson style neck with headstock adjuster.

I'll add that I don't know of a way to do a one piece neck with anything other than a curved rod truss rod installed from the back. I'm sure there must be a way but since I don't care for maple fretboards or one piece necks in general I've never investigated it. Once again, Hiscock has a good description of how to do it on his "second guitar".

Why don't you like one piece necks? Is it simply you don't care for a maple fret board?

Is the Hiscock book a good step by step process? I've got the campiano book, and another acoustic one by an english guy who I can't recall off the top of my head. I really like how they are simple and provide good step by step instructions. But the reviews online of the Hiscock book seem hit or miss.

Hiscock is to electrics what Cumpiano is for acoustics. If you are building electrics it’s most people’s go to resource.


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^^^ What he said. For anyone starting to build their own electric I always recommend Hiscock. He goes thru a very good discussion on geometry and design, wood and tools, shop safety, a whole chapter on truss rods... He then builds three different guitars using the three typical neck constructions - set, screw on and through. Follow that with a brief chapter on finish and setup, and an excellent one on electronics. I can't understand why anyone would give it a bad review



I don't like maple fretboards, I don't like finish on fretboards. I build so many different scale length instruments that I have not bothered to build a mitering setup for all the different scales so I really don't have the option of building a one piece neck and slotting it. As an engineer I have respect for all of Leo's construction and assembly tricks, as a luthier in training I have a lot more respect for the construction of a Gibson (and my attempts at duplicating it). I also happen to like double acting truss rods.

Its interesting that in his chapter on the second guitar (a tele clone), Hiscock talks about the fact that the neck is more complicated and requires a bunch of jigs and may be "crude" by some standards, but he is going to show how to duplicate what Fender makes. There is also an interesting interview with Ken Warmoth in a very recent AL where he shows some of the trick machines that they use to make necks (pendulum sanders, your basic cnc's....). He also states that many of his customers want the traditional Fender rod, not because it is better but because it is Fender.

Gotcha, I'm not so interested in doing things just like Leo did, but I do have a strat here at home that has the one piece neck and I really love the way it feels. There's just something special about it, something that I've noticed on other one piece necks. Having said that I recognize that this preference falls firmly into the intangible mojo camp of conversations, and it's likely partly my imagination. But you can play a guitar that inspires your imagination or you can play one that doesn't (I know which I prefer). Anyway digression aside, I think I'll put a pause on my neck construction, back up, and read that book. Thanks!

Hey, 'bro, build the neck any way YOU want it, thats the glory of a custom guitar. The tele clone that I'm making right now has a close to 1-3/4 nut and the neck shape is taken from a vintage Les Paul - heresy, maybe, but its my guitar and I'll do what I want to.

Thanks Freeman, part of my desire to start scratch building with a Tele is the same idea behind playing cover tunes in my high school garage band. I want to see whats inside and behind something that just works. I'm not chasing a dream with this one, just trying to come to grips with the nitty gritty details that make it work. I've found as I've learned different things about luthiery, I wouldn't say that I'm a master of any of it yet, or even consistently good, but there are certain tasks that I feel like I can confidently visualize the process for, but the neck thing still remains a little elusive and vague. I don't do well when presented with all the options, (the blessing and the curse of youtube) I'd much rather a clearly delineated process that I can work through, and then once I'm confident move onto tweaks and alternatives. So, I've got a bunch of other projects on the go right now and I think I'll try and finish a few of them off, and read that book you've suggested, then come back to the neck.

Curved channel is only for the single compression rod, and one purpose of it is to ensure that the truss rod doesn't rattle. The rod is basically a giant string, and when tensioned, it tries to pull into a straight line. If the cavity is also straight, then the rod may have a little space on one side or another to vibrate. But if the cavity is curved, the rod pulls against the convex surface and stays still.

You didn’t ask me, but I never make one piece necks. Even if I use a maple fretboard I glue it on.

My reasons are I use modern double action rod that installs right under the fretboard, and two carbon fiber rods on either side.

That curved rod thing is a PITA and doesn’t work as well.

Also multi piece necks are more stable.

I suppose you could rout from the back to about 1/4” from the top of the board and install a double rod. But why bother?

I had the Hiscock book. I found it useful. I didn’t use his plans entirely but used bits and pieces.

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