Carbon fiber fretless four-stringer

[J Posega]

I have a rotary switch, it's 4 or 5 position if I remember right. That is a good alternative if I just find out how to wire it. Last time I used one it was a nightmare to wire. Rotary switch wiring is something my brains just don't understand.

I'm not even good at regular switch wiring without a clear, color-coded pictograph. I tried wiring up a rotary for a guitar with humbuckers and when it didn't work I just gave up on it.

I'm sure someone in the Pickups and Electronics subforum could help you out.

 

[Jeff Siddall]

I have a rotary switch, it's 4 or 5 position if I remember right. That is a good alternative if I just find out how to wire it. Last time I used one it was a nightmare to wire. Rotary switch wiring is something my brains just don't understand.

They aren't so bad if you think if them as just a way to connect one thing to one of 4 or 5 (or 6 or however many) other things.

This just looks like a ton of places to put wires:

But this is the same thing:

...and at least to me makes a lot more sense

 

[MPU]

Foam trimmed and plywood pieces for bridge and strap button screws glued on. I glued some leftover cf plate on the lower bout to get some additional thickness for control cavity cover recess.

 

[MPU]

Foam trimmed and ready for the top. I use thickened epoxy to bond the pieces. There’s a small cavity on the edges of the body to get a bit more width to the glue bead between the back and top.

Body joined and taped. No need for more pressure as the pieces fit tight. Tape is only holding the pieces together while the epoxy cures. Only a little filling is needed on the seam after removing the tape.

I made a routing template for the twin Dimarzio J pickup.

 

[MPU]

I sanded the seam and routed (or cut and trimmed) the control cavity. Two layers of 400g bidirectional cf laminated to form the sides of the cavity.

 

[Max Bogosity]

Does the foam contribute much stiffness, or does it have another purpose?

 

[ardgedee]

Does the foam contribute much stiffness, or does it have another purpose?

I am curious about this too, but I assume that if nothing else it will help prevent ringing/resonances in what would otherwise be a hollow neck.

 

[RichterScale]

Also seems helpful in providing a surface for making CF sides for cavities, like with the control cavity.

 

[Max Bogosity]

Also seems helpful in providing a surface for making CF sides for cavities, like with the control cavity.

I was thinking the other way around - if all that foam hadn't been in there, it would just be a hollow body and he wouldn't need to remove the foam to create a control cavity.

 

[Max Bogosity]

That sounds negative, which isn't what I mean. I'm sure there's a good reason, I'm just not seeing it.

 

[Tom Bomb]

Foam sandwich, is my guess — rigidity and strength is the goal. Not a new concept. Tried and true. Coming along very nicely.
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[2groggy]

Foam sandwich, is my guess — rigidity and strength is the goal. Not a new concept. Tried and true. Coming along very nicely.
​

Exactly. The foam is like the centre web in an I beam. It doesn't take the compression or tension, but it holds the top and bottom surfaces apart so they don't buckle.

 

[Max Bogosity]

Exactly. The foam is like the centre web in an I beam. It doesn't take the compression or tension, but it holds the top and bottom surfaces apart so they don't buckle.

But there are also CF webs in the neck and body that look more than adequate to do that. Maybe they don’t actually connect the two surfaces or aren’t as beefy as they look.

 

[MPU]

Foam is for the rigidity and giving sides for cavities.

 

[andvari7]

What would you have to do if you wanted the reinforcement of the plywood, but wanted to go all carbon?

 

[MPU]

What would you have to do if you wanted the reinforcement of the plywood, but wanted to go all carbon?

Replace the plywood with carbon fiber plate and use threaded inserts and machine screws. I want to use the wood screws that came with the bridges and strap buttons. That's the only reason for plywood.

 

[MPU]

Today I got the neck beam leveled to proper height and angle. I fitted carbon laminate strips on both sides of the truss rod channel, made small v-shaped cavities in the joins and epoxied the strips on the neck. I didn’t take any pics because I forgot my phone at work. Basically just black dust and dripping epoxy.

 

[MPU]

And after trying to get the idea of Delano Xtender out of my head I placed an order for one. I just can’t resist the shape of Xtender and the shape of this bass combined.

 

[Barticus]

That’s funny, same for me!
It would look great in this bass.

My last build had them and planning my next build with another + one of the smaller P versions. They sound so good too!

 

[jeffmensch]

And after trying to get the idea of Delano Xtender out of my head I placed an order for one. I just can’t resist the shape of Xtender and the shape of this bass combined.

Great call. I was hoping you’d come back to your original pickup choice. Can’t wait to see (and hear) how this build turns out. Good luck!