Problem with 1976 Jazz setup

[bajerovaquero]

Hello everybody.
I´m having problems in my shop setting up a 1976 Jazz bass.
There was some random high frets, so I told the owner to make some levelling. I made the levelling properly and the bass keeps buzzing, despite the high action.
The the best setup I get with 0.4 mm of bow is 12th fret are 2.75 mm on G and 3,25 on E.
This is absurd I can go as low as 1,25mm on G and 1,75 on E in some basses.
I found no reason for buzzing, the bass is strung with 0.45 nickelwound daddarios and the fingerboard radius is 7,25"
Any tip will be appreciated.

 

[jd-ns]

Twisted neck? Ski jump? Etc?

 

[bajerovaquero]

Twisted neck? Ski jump? Etc?

I would say no. I got nice straight edges and fret rocker, theres no tall fret or high spot at this moment!? This is weird...

 

[Precision101]

What frets are buzzing? Are the frets worn?

 

[bajerovaquero]

What frets are buzzing? Are the frets worn?

Mostly over the 12th fret and some random spots over the 4-6 frets. It looks the frets have been dressed a couple of times. Right now there is no tall fret in the instrument. Ive tried to put less relief on the neck and raise the saddles, then im going over 3mm on g string...

 

[Precision101]

Mostly over the 12th fret and some random spots over the 4-6 frets. It looks the frets have been dressed a couple of times. Right now there is no tall fret in the instrument. Ive tried to put less relief on the neck and raise the saddles, then im going over 3mm on g string...

Kind of sounds like a twisted neck. If you can at least straighten out the neck and raise the saddles like you did it should eliminate some things And probably the best you can do but take that to a tech. Twisted necks are awful. You Usually find them on old used necks

 

[bajerovaquero]

Well I´m suposed to be the tech. I´ve built some basses from lumber I´ve done at least 12 refrets and I´ve built a double bass fingerboard and dressed three more... Im pretty confident I got some basic skills on fingerboards and frets.
The relief is quite uniform on both sides of the neck.
Im not good at sighting necks, but there is a posibility of a small ski ramp. How to diagnose vith confidence this?

 

[Precision101]

Well I´m suposed to be the tech. I´ve built some basses from lumber I´ve done at least 12 refrets and I´ve built a double bass fingerboard and dressed three more... Im pretty confident I got some basic skills on fingerboards and frets.
The relief is quite uniform on both sides of the neck.
Im not good at sighting necks, but there is a posibility of a small ski ramp. How to diagnose vith confidence this?

depending on the size of the hump you can file down the frets slightly to even it out or a neck shim if it's very small.