Carbon neck reinforcement

Ukemakinmecrazy

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The carbon fiber neck reinforcement rod I bough is about 1/2" wide and fairly thin. How do you install these things? Should it be installed wide side flat to the fretboard attachment surface, or thin side up? Sorry if this is a stupid question. I'm new to this.
 
The carbon fiber neck reinforcement rod I bough is about 1/2" wide and fairly thin. How do you install these things? Should it be installed wide side flat to the fretboard attachment surface, or thin side up? Sorry if this is a stupid question. I'm new to this.
Narrow side up, (similar to how beams are used). Although it may not be as necessary because nylon-type strings commonly used on smaller ukuleles, present less tension than steel strings. It will make the neck stronger though, just in case, and for extra insurance against neck warpage.
 
How thin is it? You want to install it like Rrgramps said.....but you might have a problem routing a 1/2" deep channel if its less than 1/4" thick. Most of the small router bits can only cut about 1/4" deep.

1/2" seems like serious over-kill for a ukulele. If its too skinny it won't help with twist or warping much. Maybe skip it or get a different size?
 
If your spar is oversized:

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Resharpen your plane blade :D
 
Knowing nothing about neck reinforcement except that I should do it, I bought a length of 0.236" square carbon fiber stock from The Composite Store (California). Now I'm wondering if that is of any value in installing in my tenor uke neck.

What are typical dimensions for reinforcement rod?

Do you install that stuff tight/loose?

Bless, youse!
 
That comes out to about 6 mm, i believe. If this is correct, and you can find a 6 mm router bit, route a recess into the face of your neck a bit over 6 mm and glue it in with epoxy (other glues might work as well). You want it to be a good fit, but not so tight that you have trouble inserting it into the recess. When I did one, I made a slightly oversized wood strip to fill up the gap between the CF strip and face of the neck, which gave me something to clamp on. Then I used a handplane to plane that down flush with the neck. I haven't tried to plane CF as someone suggested in the thread you responded to, but I hear that it quickly dulls edge tools and creates nasty dust that you don't want to breathe.

If you can't find the right size router bit, you could cut it with a table saw (either dado blade or multiple passes with a regular blade). That's fine, except that you end up with an overcut at each end that you need to fill with a wood insert.

I'm not sure what the minimum dimension of the CF is needed to make this worthwhile doing. I used a .125"x.325" strip oriented 90 degrees to the face of the neck, which I believe is typical for what other people use for ukes. Yours isn't quite as thick in that direction, but it's double width. I would guess that if you try to bend it under hand pressure and can't perceive any movement, then it's likely stiff enough to do some good.
 
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I use 0.125 * 0.325 rods (about 3mm * 10mm) and cut the channel on the table saw with a blade that leaves a groove that is just over 3mm wide. Very simple.
Miguel
 
I make my slot with my tablesaw. I use the rod from LMI.

Well, that sure doesn't sound too tough! Didn't think of LMI. And if it's 1/8 inch wide, a table saw kerf it's pretty much what that is.

So, Michael, do you run that a full 3/8" deep all the way through?

Thank you, by the way!
 
I get my CF rods from Goodwinds https:// goodwinds.com/carbon-fiberglass/carbon/solid-flat.html (remove the space)
Cut the slot end to end and trim what's not needed.
Miguel
 
Not sure how best to make that slot at an angle. Any good tips?

Thankee!

You don't need to make the slot at an angle. That suggestion was to help the original poster use an oversize CF rod. Make your slot at a constant depth that's slightly deeper than your CF rod.
 
You don't need to make the slot at an angle. That suggestion was to help the original poster use an oversize CF rod. Make your slot at a constant depth that's slightly deeper than your CF rod.

Many thanks to all of you who ever responded!
not being much of a woodworker, I'm wondering if the kerf on different saw blades berries. The kerf is a little bit more than 1/8 in that I installed in my practice neck just now. How snug should that rod be? Is easily slipping it in by hand too loose?

I have ordered a 1/8 by 3/8 inch rod from LMI. it is 2 ft long and my best guess is that I can get to ukulele is out of that. Good enough for experimentation.

Chuck Barnett
 
Of course you could do what I do and not put in carbon fiber reinforcement at all. Seems to work for me. Instructions below:

1) Do not purchase carbon fiber rod
2) Do not cut kerf in neck
3) Do not insert carbon fiber rod
4) Glue ebony fretboard to neck
5) Attach neck to body

I will get back to you in 30 years to see how that works out. See: limited warranty. End of civilization voids warranty.
 
Sequoia,
What wood do you use for your necks and how thick are they? What length necks do you make?
Tom
 
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Of course you could do what I do and not put in carbon fiber reinforcement at all. Seems to work for me. Instructions below:

1) Do not purchase carbon fiber rod
2) Do not cut kerf in neck
3) Do not insert carbon fiber rod
4) Glue ebony fretboard to neck
5) Attach neck to body

I will get back to you in 30 years to see how that works out. See: limited warranty. End of civilization voids warranty.

Yep, I'm catching on... I could have guessed that this would be your method. 😃

Thanks,

Chuck Barnett
 
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