Semi Hollow UBass

[potomac]

My new project is an UBass, in a semi hollow design. I'll try to use cheap piezo pickups, a large diameter disc inside the body and an "under saddle type" in the bridge.

I'll use a balance pot to mix the signals of the both pickups, I'm not sure if they're really sound different, who knows? They are cheap, so I'll give them a try.

Maple wood for the body as a sandwich with walnut in between. Only the top maple layer is hollow, the resonating top (1/8" thick) is stabilized by walnut and a cross of red oak wood and has one simple f-hole.

In the first pic you can see a comparison of size between the my U Bass design and a Strat.

 

[Jim Ingraham]

looks cool!...subbed

 

[yeelaberbin]

Two piezos! Waow, it'll blast...

 

[potomac]

I don't know, let's see what happens....

Two different piezos, so I think there will be a difference in sound. Piezos are cheap - no risk.

I usually build Cigar Box Guitars or basses built from cheap lumber. I do not expect rocket science.

 

[yeelaberbin]

It also happens the type of strings you'll use.
Pahoehoes or Thunderguts ?

 

[potomac]

Thunderguts, I think they sound a little more brilliant, right?

 

[vmabus]

^ They're not as sticky, either.

 

[potomac]

I was not sure about the shape of the neck pocket. Because of the round shape it'll be more ergonomic.

 

[potomac]

The edges of the body are rounded now.

I'll use that type of tuning peg for the Bass. The diameter of the axis should be thick enough to make the slot a little bit bigger for the strings.

 

[potomac]

Today, I started building the maple wood neck. It has an angled headstock.

 

[potomac]

Neck and Neck Pocket

 

[DerekW]

Subbed!

 

[Feral Feline]

Sweet!

Maybe get the schematics for Fdeck's HPF-Pre (they're free) and integrate it with the build; add a polarity switch for the piezos, in case you get phase cancellation when blending them.

 

[Jonny5bass]

Looks good! I'm in.

 

[dunic]

very curious how this will turn out. what will you use for electronics (for the piezos)?

 

[potomac]

very curious how this will turn out. what will you use for electronics (for the piezos)?

I'll try that circuit

 

[potomac]

Used my new LMI fret slotting system for the fretboard.
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[Invalid or Expired Link Removed]

 

[potomac]

After a long break, I'm back again!

Next steps are neck shaping and installing the frets.

 

[Jisch]

Very nice! I'm in.

I converted a cheap Rogue baritone Uke to a bass using Thundergut strings. I used standard bass tuners like you have there, I filed the slots wide enough for each string - it worked fine for all except the E string. It's really thick! I got the slot wide enough, but one wrap of that string occupies all of the tuning peg. I resorted to using a zip tie to hold the wrap in place, it's ugly, but it works. I use mine specifically to play along with my wife on her uke, so I am not concerned about how it looks. I guess with enough time and motivation I could figure out a better solution. Those strings stretch a LOT, even once they are fully stretched, getting the string to move even a quarter step is several full turns on the key.

I look forward to seeing this completed!

 

[potomac]

Very nice! I'm in.

I converted a cheap Rogue baritone Uke to a bass using Thundergut strings. I used standard bass tuners like you have there, I filed the slots wide enough for each string - it worked fine for all except the E string. It's really thick! I got the slot wide enough, but one wrap of that string occupies all of the tuning peg. I resorted to using a zip tie to hold the wrap in place, it's ugly, but it works. I use mine specifically to play along with my wife on her uke, so I am not concerned about how it looks. I guess with enough time and motivation I could figure out a better solution. Those strings stretch a LOT, even once they are fully stretched, getting the string to move even a quarter step is several full turns on the key.

I look forward to seeing this completed!

Thanks for your comment, yes, these are simple bass tuning pegs. I tried to find tuning pegs a little bit wider on the axis, so that there'll be more material to make the slots wider.