Bass neck reinforcement

[Jim88]

Hello,,greetings

Looking for a bit of advice please,

About to start an fretless acoustic bass ,build # 6.

I have ordered an 2 way truss rod and 2 lengths of carbon fibre, Is it ok to use a combination of 2 carbon fibre Rods with a truss rod,?

Or is it counter productive,? Or just use the carbon fibre? Just the truss rod? Bearing in mind its to be fretless,

Thanks

[mirwa]

Good combination of both if your going for a slender neck

Steve

[Rudy4]

I'll be in the minority, but I'm not a big fan of removing material in the central portion of the neck and then trying to add back in material to compensate for what's been removed.

I'm also not a fan of carbon strips. They are expensive and I don't think there's really a big advantage to using them.

I'm working on a bass right now and it has a single channel cut for a double action truss rod, that's it.

[tadol]

NCAL (Northern Cal Asso of Luthiers) had a Zoom meeting and presentation by Roger Siminoff, who has spent many years studying neck structure and truss rod design, which discusses much of this. We neglected to hit the”record” button at the very start, but it still has alot of useful and very interesting information and is worth a look if you are interested in neck structure and truss rods -

It picks up discussing how early Gibson necks look like they were vertically laminated, as many musicians felt it made a stronger neck, but that they actually just routed a grooove down the back of the neck and inlayed a strip of dyed pearwood - take it away Roger -

https://vimeo.com/455334910

[Th'Axe]

Carbon can be VERY effective stiffening a neck, but you must be aware of certain factors. Epoxies work best. And the part must be very clean, and prepped appropriately prior to bond. Properly bonded, and shaped to serve the load design, a precured carbon unidirectional strip (or 2) can nearly negate any effect of the truss rod. You would be amazed how much the performance of a composite part can change with the addition of 30-40 thousandths of an inch of uni carbon. Big drawbacks=(1) dangers of dust inhalation. Mask up! (2) carbon dust stains spruce worse than rosewood (3) diamond saw is the best cutter (if you use a vacuum to capture the dust coming off the cut) (4) clean bond prep is everything. Using precured requires enough prep to the carbon to offer strong mechanical bond, as it is by nature a secondary bond. (5) leave it buried rather than exposed, it's just easier and cleaner

[Jim88]

Thanks for the responses,,I did listen to the video with Roger Siminoff, interesting talk, thanks,

Best regards,,,