truss rod help

[nivek92]

hello all, i am working on my first ever guitar build, and i decided to make my own neck to go with it. i have the profile of the neck cut already (probably a bad idea on my part) and i have a truss rod from stewmac, i think it was called traditional truss rod, or something like that, anyway, it is the kind that you have to cut and tap. i am capable of cutting and tapping, but the problem is it came with absolutely no instructions so i dont know exactly where to cut it or how big the channel is supposed to be. i chose this rod over the hodrod model because i am stubborn and would prefer the adjustment to be at the headstock, in hindsight, i suppose i would have been better off just going with the hotrod but w/e. so could anyone tell me where and how big the route should be and how long the rod should be (its a 25.5 scale neck) or possibly even point me in the direction of good resources/previous threads?

[LocustPlague]

You are going to have to route a curved channel to use the vintage style truss rod. This blueprint should have all of the info you need.

http://i153.photobucket.com/albums/s...lueprint-1.jpg

[nivek92]

thank you very much, no i have one more question, i was planning on routing from the front and putting a fretboard on top, should i just scrap that idea completely or will it still work? i didnt realize that the channel had to be curved so would i have to put a strip of wood in the channel with a curve on it or could just the flat fretboard on top be fine? it doesnt seem like that would work out but im no expert.
also, what is the screw marked at 15? is this necessary? i have never heard of this.

[Dr.Ow!]

The cambered rod channel is a modded straight bottom channel with an added 1/32"-1/16" of extra depth at around the 6th fret or, 1/3 of the nut to body length from the nut, on the jig I made.-this is done to apply a force to equalibriate at the point where the neck and fb want to drop the max in theory. I got my info from the Bennedeto archtop book and went from there. A book explaining all this is a good idea so you have the best chance of getting it right. Not great to have a poor neck after all that work and material invested.

A 2 step rout is nice too. The second cut is 5/8" wide for a 5/8"cap piece that holds the rod in-making a 'T' shaped rout in cross section. The 5/8"rout is done to a depth to establish a perfect 1/4 x 1/4" channel and is fail safe. I botched my first neck build by driving in the fill piece too tight and locked in the t-rod so it did nothing at all. It needs to be free in the channel a smidge. This is when I went to the 5/8 top piece.

FWIW-Pg 85 in Benedetto's book shows the channel 7/16" deep running flat from the body end to about midway, then it begins a curved lift to 3/8" at the nut.

[nivek92]

thank you both. so what would be the best way to make the cambered route? i have access to a mill in my schools shop class which i thought would make everything much easier, but there are only square bits. will that be okay? and also, does the bottom of the route need to be curved or could i get away with making the actual truss rod route two tier? like route the whole thing to the shallow depth, and then more towards the middle just make another pass a little lower. i am still in high school so i am actually getting credit in my shop class for making this which works out great because i dont have the tools necessary for a lot of this, i have a router, but it seems to me that a mill would be much safer than a router on a crude jig. am i right?

[Dr.Ow!]

The router and jig are ideal actually. The important thing is having a clear understanding of what is necessary for your particular neck. a mahogany neck for instance needs a bit more mass due to its lower strength, whereas a maple, ash neck can be thinner at the nut generally speaking. The key to good t-rod effectiveness is in the geometry. The pull of the rod needs to beyond what in engineering is referred to as the 'neutral axis'. In this case that is the back side of the neck. I am going from memory of the MIMF Tele plan I built from-I can dig it out a send you the exact specs if you haven't a Tele plan. But for now here's what I recall-
Tele neck back taper thickness-without the 1/4 FB-(from 4/4 min. well seasoned stock, jointed and planed to 13/16+"
@#1 fret - 5/8"
@#12fret - 13/16" net 3/16-5/32" taper
Add 1/4 F/B for net structural thickness-@#1 - 7/8"
@#12 - 1&1/16"
OK. so that means the effective nuetral axis is on a line about 7/16"@#1 and 9/16-"@ #12. To have an effective rod it must be placed below this imagined line called neutral axis Most efficient is right on the backside of the neck obviously, but we can't do that, so we need to get the rod as close as possible to the back plane of the neck, but keep enough wood in play so the neck never splits. For maple/ash that is 5/32" IMO" MINIMUM at the nut, but 1/4" better so any possibility of splitting is minimized. This is also the reason the core box round nose cutter is preferred for the channel bottom as it increases the strength here quite well.

The Benedetto dimensions are for Maple so it is a good ref for Tele necks. Using his dim's you then net- @#1 - 5/8"-3/8"=1/4" and @#12 - 13/16-7/17=3/8". It is easy to see what is happening regards the neutral axis and the rod's pull effect when you draw it out full size-which of course you will do. Doing my best to be clear in words here, where plans and full size draw's are best.

Regards a jig for a router. Basically it is a simple affair. It just needs to be executed well. Using a mill(or overarm production router) may be a cinch for a straight channel rout, but just as difficult to jig up for the well done accurate camber or lifted channel. Either or method of course, but making the routing jig you will always have it, or can pass it on.

In words here's what I have for my jig- I began with a good clear and straight grained fir & DRY! full 4x4 in rough, jointed on the jointer & table saw straight and true all 4 faces net 3.75" . Then I layed out the exact locations of the flat and then the rise-only 1/16 - 3/32" but it matters to get this right- over the 25.5"scale length. In practice I use the same jig for 25" scales also-no diff.
I drew that on both sides of the 4x4 using a stiff batten to get the shallow and tiny amount of curve from flat to the rise at the nut. Then with a sharp smoothing plane removed that small amount of material accurately and to a true flat face-so in effect the camber profile of the trench is on this top face of the 4x4. OK.
Then I rip that 4x4 in half down the middle. Now have 2 halves-a R&L pair. These are the rails the router will ride on. They are mounted on a base piece of good stable flat and true & DRY! wood in a manner as to obtain a width between them for the neck blank to be temporarily mounted on the jig center line for the rout operation. the routers base is kept on line during the routing by small fence pieces on the outboard edges of the riding rails-this is determined by the router base dimensions+1/32-1/16" for clearance, and requires designing the jig in advance for the various geometric req's. The other factor in the jig making is to get the rails at the correct height above the base piece they mount on to accommodate whatever cutters you have and are using. An involved little number it is indeed, but once made whips out an accurate truss channel.
Sorry this explanation is long but it is one of those seeming simple things, but the devil's in the details. It is not too easy whatever approach one takes and why most don't venture here.
If you want more info let me know-I can post up a quick sketch with dim's from my jig and take a pic or 2 of it if you want to go this route.
In the mean time here is some shots of my Tele Cust.-if they will post up correct. It don't Twang as good as a real Tele I know but she do rock good

[Dr.Ow!]

I just read again and your question about a tiered cut is a good method for a one-off without needing any hassle with a jig.
What I would is use a 1/4 core box cutter if you need to buy a cutter. The straight cutter is fine though too.
A tier as you have mentioned to the midpoint will work good. You can then use a scraping tool to make a nice gradual camber to the nut-its only a 1/16 almost nothing, but it is an effective little detail. You can fab a scrapper from various items-screwdriver, 1/4" chisel etc. It helps to grind some of the side away so for a 1/4" slot use a 7/32" scraper. I save my worn out files for the hardned/tempered steel-they make decent chisels too if your not too hard on them. On the grinder you make whatever profile you need- for the core box round just grind that to suit.
Reading forum descriptions it can sound like it has to be exact. Not really. We all try to get as close to it, then the result is pretty good. So as you say it can be near enough and will work fine.

[nivek92]

wow! thank you so very much. due to my summer job budget and the fact that i am going to college 9 1/2 hours away next year, i may not make another guitar for quite a while, so i would consider this one-off. (although i was considering building one more just to sell on craigslist to help pay for this) the only neck blueprint i have is the one posted above by locust plague, which i think will do, and the body blueprint was the one that was posted by, i think, terry downs? but any other information or plans would be appreciated.

[nivek92]

argh.. im in class right now so ive been going back and forth between this and work, my login timed out and my post got cut off, anyway, thats a really nice lookin guitar you got there. thanks for your help. i think im gonna just use the mill. i also have a set of carving chisels so i think that will do. i'll talk to my shop teacher. i have shop class at 9:45 so i'll try and do some then and maybe a little after school. i will try to post some progress later this afternoon. maybe some pics. back to your guitar tho. what kind of controls do you have on that? i noticed its a little different than normal. and is that control plate rosewood? its very itersting. i also like the headstock with the flame and the dye on the back.

[Dr.Ow!]

This project started as a true to form Tele, along with another w/ a walnut top plate. This one was to be a Deluxe w/ Hmbkr routs and using a Hipshot HT Bridge, not Tele type. For various reasons it became what it is.The neck was a spare glue up for some acoustics which had enough headstock to go to Tele profile. Sort of the orphaned step child syndrome, and as it turned out a pretty good one by luck and by gosh in the Tone Dept. F/B is rock Maple and the frets are short at about .035 +/- finished as I recall. Someday I'll refret it to a more standard height from this SG fretless-wonder style. It is fun to play this way for sliding blues stuff but can be hand fatiguing in many positions.

The controls I have work very well as I originally set them up-intending as only a look-see experiment. I am now loathe to touch it for fear I'd not get it back. Also I used cheap 18ga non-tinned pvc wire I had laying around-this was a throw together project to fill some time, but then it all showed up. Funny how that can happen at times.

It is 2 vol, 1 Tone. I think(don't remember exact)the hmbkr V is 500k,the Tele B is def'ly 250k, and the tone 250k. Or the tone is 500 and the H v is 250. I have a big russian .047 pio cap. It overall tends still to be bright so a .068 or .10 cap may be a good change someday.

The mini switch is goes to series/parellel Hmbkr.

The control plates are a solution to #1 not wanting waste the only good sheet metal I had-ie ss- on the plate, and #2 I'd routed the longer cavity for the Deluxe intending a 4 knob control set per the Dlx, but in the standard Tele config/look.

The 2 bods sat through winter, and then I scrapped my first Tele build(Oak/Fir)had the parts, looked at this cherry top, and! The control plates are actually kind of involved as I wanted the woodwork challenge of a clean no-screws look. I had a few LMI peghead plates in Madagascar Rosewood. Under that face is a white oak box basically that tight fits into the cavitys-both the LP switch and pots. There are screws from the back into these. I intended to make a a brass string-thru plate for the back but in use have found the ash to be good enough as-is-for now. On the long hual ss or brass plate is a definite. It is a junkyard dog so no big deal and I like it now as-is. The red veneer is actually LMI bloodwood they sell.

The rout on the Mill should be a cinch and easy for your instructor to show you through if you need. The scraper thing is a great method and was a much used techniqued that is ancient. A decent screwdriver with a fresh grind will do it-don't bother honing it-works best right off the grinder.

If you want a photo post of the Tele plans neck- can do tonite.

Gooday

[nivek92]

well i didnt really get much done yesterday but i think i know pretty much what im gonna do, now i just gotta mark the details and actually do it.. we'll see how it works out. but i would really appreciate if you could post those plans or send me a PM, whatever you wanna do. thank you