Converting a Hofner style violin bass to a 5 string

Ali Express sells one, with cheesy ferrules instead of a tailpiece.

 

Seems like a faff, and the design of a violin bass doesn't lend itself to a fifth string.

Steaming off the neck, fitting in a custom wider neck, somehow landscaping a wider neck heel into the body, finding pickups with a wide enough sensing area that still sound 'Hofner', finding a wider bridge and a 5-string trapeze tailpiece, refinishing... it all seems like a lot of work. And then the top might start collapsing under the additional tension of a fifth string.

 

This is my main concern

 

Don't.
The structure of a four string Hofner violin bass is not built for five strings.
It has to be braced for five from the start.

 

.tcejorp fo dnik taht rof sdnasuoht egrahc (,ereh erutats gniklat t'nera ew) sreihtul llams yhw dnatsrednu nac uoy ebyam won, now maybe you can understand why small luthiers (we aren't talking stature here,) charge thousands for that kind of project.

Spoiler

I'm not doing that again; it's too much work.

 

Your best bet is to contact a builder on there and see what they say. It might just have a block down at the ferrules.

 

In my dealings with them they have been very responsive to my whims. If you establish communication and tell them you want that flame maple back intact and a 5 string tailpiece, you are liable to get an email in a week or ten days giving you a link to their new design. Especially if you point out the design flaws of through body and the advantages of a tail piece with a floating bridge.

 

Those basses already have very narrow string spacing at the bridge.

 

That is the factory store. Here is your contact information; left side "Service Center." You have to go through Aliexpress just like on ebay, so ya gotta join before you can talk..
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