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In my planning for my next build, I hope to install carbon rods in the neck. I have read that they are beneficial to the neck, especially when it will bear five course strings, and have a relatively long scale length...

Now...doing even more research yeilds the fact that Carbon rods are used for kites, etcetera. If I can get the optimum width/depth, could I just order some from Ebay and use them?

Another question is, what mm width/diameter rods should I use in the neck, as I am going to go as slim as possible for my small hands, bearing in mind the sheer tensions the ten strings will create. I endeavour to have a carbon rod either side of the truss rod.

Thanks for reading this.Sam Price39026.1138194444

Thanks Hesh. Your questions were on the tip o' me fingertips, honest!!!

Sam,

I use the Stew Mac 0.2" ones.

Hesh,

I've used cf-rods in all of the necks I have built and have had no issues at all in terms of the truss rod still operating.

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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

I use LMI 1/8" X 3/8" each side of the truss rod, right down under the FB extension.

Colin

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

sam, am i correct in assuming you are going to build a cittern, irish bouzouki, style instrument?

if so i think would go for the 1/8 x 1/4 cf, or at the most 3/32 x 3/8 if you can find it.

i don't think that the kite rods would be appropriate, in that they are designed to bend relatively easily, and the cf is there as much for durability perhaps more than stiffness.

you might want to go to one of the string tension calculators such as that at d/addario's web site to take find out exactly what stress you are going to be putting on.

i'm guessing that a light guage five course (duh,edit, get it right, edit ) 10 string set will not put too terribly much more tension on than your medium guage 6 string set. crazymanmichael39025.7452083333

Some builders use round fiber rods...Mark Swanson, for one. Maybe he'll join in here.

Just to remind you... We also have a sponsor who sells these rods in custom sizes

http://www.jameswattsguitars.com/LAC.htm

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Hmm, I thought the Kite rods were actually tubing, lighter and a little flexible, great for a Kite but you want solid form like Jim Watts sells of Los Alamos for guitar necks or you may be defeating the purpose.

Cheers

Kim

Thanks. You guys are great.

I needed to know, for I can now finalise my large LMI order..

Sam, I've used the 3/16" x 1/4" carbon fibre rod that LMI sell. Jim has the same size.

An easy way to install them is if you are using a router table to cut a 1/4" slot for a LMI style or Allied style double action truss rod slot. Cut your truss rod slot, then fit a piece of wood 3/8" thick double sided taped to the fence and cut a 1/4" deep slot (in a couple of passes), flip the neck blank around and cut the another slot. You'll end up with two slots 1/8" from the edge of the truss rod slot. Epoxy in the carbon fibre rod and laminate in a 1/4" wide wood filler strip over top at the same time. The carbon fibre should be laminated in through the headstock and will really strengthen it. Clamp it down, then remove the squeeze out, then clamp down with wax paper under your clamping caul. Once dry, hand plane the excess filler strip flush with the neck. Once dry, the carbon fibre that protrudes above the headstock can be easily removed with a dremel cutoff wheel. (Please wear a dust mask as the carbon fibre dust is really nasty).

Another carbon fibre tip is wear light work gloves when you are working with it as it has fine fibres that leave splinters that can be painful.

Cutting and laminating in the rod the way described above won't provide the strength laminating it in on the 3/16" edge but it'll add plenty of strength.Anthony Z39026.9610185185

Hey guys... I found some carbon fiber strip for pretty cheap. Not sure if this
is what you'd want to use, but here it is:

http://www.dragonplate.com/ecart/categories.asp?cID=20

I've never ordered from them, so I can't comment on that. Just passing
along info! :)

The thing about carbon fiber is that the direction of the fibers within the rod matters. For example, the flat sheets they make bike bodies out of bend easily into a tube one way but turn the sheet ninety degrees and it's completely rigid. The best rods to use for stiffness are 'pultruded' (I think that's the proper spelling) which means that all fibers are aligned lengthwise in the rod for maximum stiffness. If they were all aligned the other way then the rod could be really bendy along its length and so everything in between is possible.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Colin, or someone who uses carbon fiber in their necks. Does it add anything to the tone or sustain of the guitar? I haven't felt the need to use it for strength - I have never had to tighten the truss rod in any of my guitars or seen any sign of neck movement. But if it adds anything to the sound of the guitar I would gladly go the expense of using it.

                  Peace, Paul

[QUOTE=paul harrell] Colin, or someone who uses carbon fiber in their necks. Does it add anything to the tone or sustain of the guitar? I haven't felt the need to use it for strength - I have never had to tighten the truss rod in any of my guitars or seen any sign of neck movement. But if it adds anything to the sound of the guitar I would gladly go the expense of using it.

                      Peac e,   Paul[/QUOTE]

Paul,

I can't definitively answer as I've always used them and haven't done a neck without to compare, but the main reason I use them is after reading an article by Mike Doolin where he thought that the cf rods helped eliminate dead spots on the neck and help overall sustain.Dave White39028.2504282407

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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

I install CF rods (Los Alamos Composites) on 14 fret necks but not 12 fret necks. That said, I can definitely "feel" more sustain in the 14 fretters. It could, however, be the effect of the longer neck, but since I've only made 2 longer necks, I really can't say.

Sam, in addition to the CF rods, you might also consider laminating in order to further stabilize such a long neck. As far as CF cross-sectional dimensions, do a full scale drawing in choosing size to make sure you don't file, scrape or sand through the wood and expose CF. The closer you can imbed these to the centerline, the better.

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JJ
Napa, CA
http://www.DonohueGuitars.com