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What would be a safe minimum amount of wood thickness to leave under a stewmac two way hotrod?
I am hoping to get down around .120 ?

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Lance@LuthiersForum.com

I like to keep a full 1/8 under it. But that's just me.

Thanks Paul, that is what I needed to know, I have a little over .220 to work with, looks like I can take it down .095 more. That is not quite as thin as I wanted to make it, but boy its close!

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Lance@LuthiersForum.com

Be Careful....

In the late 90's I had to rebuild a batch of 4 necks, (glued up, bound,
inlayed, sanded and ready to go in the spray room) after the Hotrod
popped through the back of each and every one. I don't recall the exact
measurements, but we had laid them in to a dadoed slot with at least       
.110"-.120" behind them. That happened around 5:00, and after a very
late night I had another batch of four ready to finish sand by 10:00 the
next morning and in the spray room by lunch. That was the last time I've
used one.

I really don't care for the design, because unless you cut a rounded slot to
contact the rod the entire length, the wood directly behind the brass
block will have to bear the entire load. This puts all of the pressure on
less than a quarter square inch of wood. Compression rods of course will
spread the pressure the most evenly and in a different direction, so you
can easily go under .100" with those. For two way rods I strongly prefer
the Allied Lutherie or LMI rods. I just see no good reason to have a double
action rod as tall as the the Hotrod. Of course my experience left me a
little less than objective. My $.02...

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Eschew obfuscation, espouse elucidation.

I prefer to use their truss "Hot” rod with the adjustment at the headstock. I'm not convinced it should be used if adjustment is via the sound box. I like a slim neck where the end point sits and for me it’s just gets too thin.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

GREAT question!

I had the same thought today while gluing up a neck and wondered just how far I could get by sanding it down to shape. As in another thread, I have wondered about making a thin and slender neck, and thought since I have the guitar to try it out on I would sand a little further than normal.

Thanks for bringing this question up!

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Reguards,

Ken H

I had a trus rod break out the back side of a neck a few years ago so I like to have as much as possible behind the rod. When I use a rod, I use the LMI version as it is slightly thinner front to back than some others. I am thinking about going back to the good ol' compression rod though. Most of my little ladder buitars don't have truss rods but just a pair of 3/16x1/4 carbon fiber rods seperated by about an inch. I love making those necks without rods as there is no adjustment required and you don't have to make access or hide anything. Plus they are very light and stiff necks.

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Tickle your guitar daily, and it'll tickle you back.

John, I've been thinking of going trussrodless (is that a word?) for a while now, with the advent of carbon fibre we have necks that are so stiff now that just getting the truss rod to act is difficult.

I've got four vintage Martins the earliest with an ebony neck reinforcment under the fingerboard the other three (two pre-war one 63) that had the steel T bar. none of these necks have moved and are all very playable still.

Food for thought.

But until then I use LMI rods with at least 1/8" under the rod.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

[QUOTE=Colin S] John, I've been thinking of going trussrodless (is that a word?) for a while now, with the advent of carbon fibre we have necks that are so stiff now that just getting the truss rod to act is difficult.
Colin[/QUOTE]

It's just hard selling people on that sometimes. But seriouly on a 12 fret neck there is little need when you have carbon fiber. I put everything together as flat as I can and light gauge strings give me just the relief I want.

Speaking of carbon fiber, James, I need to order more!!!
Get your fiber from OLF's own Los Alamos Composites!!!

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Tickle your guitar daily, and it'll tickle you back.

John H, don't you feel the need for adjustability in the relief of the neck? Or are the clientelle of your little gems pretty much of the same music/playing style so they all want the same relief?

I always use a simple compression rod. They have less tendency to pop out the back of the neck or push the fretboard off. Also, it makes for a lighter neck.

If you tighten the rod up before you level the frets, then you have a little dual adjustability.

I install the rods in a slot that curves up at the headstock end about 1/16". Seems to make them work better.

On my last couple I have been building the neck and neck block first and then routing along the two a 3/4 x 7/16 opening and glueing in a piece of hardwood surrounded by carbon fiber. This allows the extension to run past the neck joint, pretty normal stuff. On the 12 fretters I have been adding another fiber piece straight up the middle but when I use a truss rod it gets inlayed into the hardwood so the meat behind the rod end is 2 pieces laminated and the force is not all on the softer mahogany. None of these have been built up long enough to give any real feedback, but no problems so far. I have been using Osage as the hardwood because I read it is little affected by humidity and that like pernambuco, sound travels along it very quickly, even under stress. I like the idea of having something like that in the neck but can't offer any ideas on how it affects sound. I have been using the hot rod, but might switch now after reading this thread. I have really been wanting to try the new Allied rods. Does anyone out there make their own 2 way rods?

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Burton
http://www.legeytinstruments.com
Brookline, MA.

As to the Martin T-bar and O-beam necks, I get those in all the time
to be straightened. At around $320-$400 for a compression refret, most
players wish they had truss rods.

Now there are certainly composite reinforcements today that are much
stiffer, and likely will truly never move at all. That's not my issue with
non-adjustable necks however. I truly do not mean to offend anyone here
and I wish I could find softer words to describe, but I find the idea of
non-adjustable relief to be a bit arrogant and presumptuous. My issue is
that there is not and will never be a universally correct amount of
relief or straightness. Even within the same style of music, different
players benefit from different setups, and even a players preferences and
demands on an instrument can change through time.

I guess I just see adjustablitiy as a necessity to make the most perfectly
ideal setup for any individual player, and I see no real advantages to
removing it. A neck can still be stiffened considerably without making it
entirely non-adjustable if that is what you like. I also believe that strongly
in designing servicability rather than indestructibility.

Sorry to hijack the thread for my rant. My point with the Hotrod is just to
be very careful in your thinning of a neck. I don't use them because I
cannot find any single advantage that they hold over the LMI/Allied
Lutherie designs other than a few days less shipping time for me.

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Eschew obfuscation, espouse elucidation.

[QUOTE=Pwoolson] John H, don't you feel the need for adjustability in the relief of the neck? Or are the clientelle of your little gems pretty much of the same music/playing style so they all want the same relief?[/QUOTE]

I will discuss that with the client but find that most don't know too much about relief anyway so the way I build the neck gives what I think is just right.
It's very easy to add a little more when levelling the fingerboard prior to fretting though.
I just find that adjustability is not that critical on a 12 fret neck and I just love the lightness I get by not installing that metal bar.

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Tickle your guitar daily, and it'll tickle you back.

   If I was thicknessing a close area, I would set up a dial indicator over a sharp pin/thickness gage and take the thinnest section down first, checking up and down the neck, then work everything else into that! That would be the safest way, I would think.

   Even though one would have an 8th at the bottom on the bias it would be something less, especially at the nut.

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

Here's a small bodied 12 fret in my shop right now. I'm not sure what non-
adjustable reinforcement was used, but it has a spanish heel to boot.



My focus is in repair and maintenance, so naturally my emphasis is on
serviceability and adjustability. I hold a very firm philosophy that if you want
an instrument to be around for 50 or 100 years then movement and settling
of all parts should be anticipated in the design. Of course a non-adjustable
neck is never really non-adjustable, it's just not as convenient of an
adjustment. For this I guess it's a judgment call on the part of the builder
and buyer, but I find the ability to make even minute adjustments invaluable
to fine tuning a setup for a particular player.

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Eschew obfuscation, espouse elucidation.

A note here: carbon fibre reinforcements are in no way stronger and stiffer than a steel tube or T-bar. They're stronger and stiffer *for their weight*, and they don't have memory, but that's really just about it.

I'll keep installing truss rods in my guitars.

The guitars I am talking about are reproductions of guitars built in the early part of the last century and did not have truss rods in their necks at that time. In order to keep them feeling like the real deal I don't want the extra weight. It is a very telltale thing to pick one up and feel that weight. The carbon fiber does the trick for me. I am using two 3/16 x 1/4 rods seperated by less than an inch of wood. They are nice and light and very stiff, should one of them fail, I'll fix it.

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Tickle your guitar daily, and it'll tickle you back.

I guess it depends on the kind of wood in the neck. If it's a hickory neck, then soak it good first, then I recommend a good 1.25" of filet mignon, or 1" of a center cut pork chop. The wetter the wood, the better the smoke.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

[QUOTE=Colin S] John, I've been thinking of going trussrodless (is that a word?) for a while now, with the advent of carbon fibre we have necks that are so stiff now that just getting the truss rod to act is difficult.

Colin[/QUOTE]

Colin,

I've seen this quoted a number of times. Every neck I have made on an acoustic has had a cf rod on either side of the truss rod (usually the Gotoh 2 way adjustable ones) and I have never had any problem in getting the truss rod to engage and do it's job, either adding or taking away relief, with the slightest turn. Maybe I'm not using as big cf rods or embedding them as deeply as others do. I think the cf rods do as much in terms of the neck "resonance" and making notes sound and play evenly all over the neck - Mike Doolin says something to this effect in his fabulous series of intonation articles.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

"My issue is that there is not and will never be a universally correct amount of relief or straightness. Even within the same style of music, different
players benefit from different setups, "

Sorry to take this discussion down a level or two but...the statement above makes perfect sense to me. However, I don't really understand how relief relates to the action you are trying to set up, if you are aiming for lower action, do you use more or less relief?

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David White, Toronto

"All my favourite singers can't sing."