Official Luthiers Forum!
http://www.luthiersforum.com/forum/

Inlaying carbon fiber beams in neck question
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=26296
Page 1 of 1

Author:  Stefan [ Sun Feb 28, 2010 12:47 pm ]
Post subject:  Inlaying carbon fiber beams in neck question

Hello all,

I'm inlaying 2 carbon fiber beams, rectangular cross section into my neck either side of the truss rod. Question is; does it matter if the channel is a tad too deep? This would mean that when the beams are epoxied in place there would still be a little gap above the carbon fiber beam and below the fingerboard. My worry about trying to get it perfectly flush is that it may end up being a tad proud, I don't want to be in that situation because it doesn't seem like the type of stuff you can plane flush. The other idea is to make the channel deeper yet then use filler strips above it, like many do with their truss rods.

In other news I installed LMI double action truss rods in two blanks, using filler strips, glued with epoxy. After the glue set I decided to give the nut a twist to see if was working, the nut did not want to turn very much at all. I panicked and assumed that the epoxy (though thickened with west systems microfiber) had oozed down and gummed up the threads. Spent last night doing a rather crappy job removing one of the filler strips with a 1/4" chisel to remove the rod. Bugger works fine, of course it didn't want to move because the neck blank has not yet been thinned and carved, can't bend that much rock maple! Now have a bit of repair work to do to get back to square one! learning curves eh?

Many thanks for your thoughts,

Stefan

Author:  Rod True [ Sun Feb 28, 2010 1:07 pm ]
Post subject:  Re: Inlaying carbon fiber beams in neck question

The spline over the CF would be fine I think. If you set the CF down just a few 0.001" you can plane down the neck surface to the level of the CF. Then you could cut the channel for the truss rod. Or you could install the truss rod with a spline over that and then plane down the entire neck surface to the level of the CF.

Author:  Jon L. Nixon [ Sun Feb 28, 2010 1:14 pm ]
Post subject:  Re: Inlaying carbon fiber beams in neck question

If your CF rods are just a bit proud, sanding them flush is usually not a problem.

If you glue on your FB with epoxy, you can set them down a hair deep and then fill the gap with a little extra glue. I have done this many times with no problems.

Author:  Darryl Young [ Sun Feb 28, 2010 2:33 pm ]
Post subject:  Re: Inlaying carbon fiber beams in neck question

The closer the carbon is to the back of the neck, the more effective it will be. At some point around the middle of the neck, there is neither tension nor compresson. To be most effective, locating the carbon where the stress is highest would work best. Also, carbon is better at resisting tension than compression......so locating it as far toward the rear of the neck as is practicle would seem the best location. And you still have the dense fretboard on the other side to resist compression.

Author:  KiwiCraig [ Sun Feb 28, 2010 5:47 pm ]
Post subject:  Re: Inlaying carbon fiber beams in neck question

I install my C.F. a hair below the surface to allow for final leveling. In the pic below you'll also note they are splayed wider at the heel end.
I route the Allied two way trussrod deeper at the heel end and employ a cover spline . This helps it function and also allows access for adjustment at the heel end with my adjustable neck system.

Attachment:
ADJUSTABLES121.jpg


Two 5/16 "C.F. tubes are installed through the heel which connect to the rectangular C.F. sections

Author:  Terence Kennedy [ Sun Feb 28, 2010 6:53 pm ]
Post subject:  Re: Inlaying carbon fiber beams in neck question

I usually leave them maybe a 64th deep. I don't think it matters. Tightbond won't stick to them and epoxy will fill the gap.
Seems like they usually have a bit of longitudinal bow so even if your channel is dead flat they'll rock a little.
TJK

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/