Jazz bass neck holes don't quite align with Jazz body holes... What to do?

[rwillett]

So I've made a tool to hold everything safe, secure and flat. It's now adjustable and is designed for 9.25" radius necks. Its easy enough to make it for flatter or rounder necks. I can move and adust the position of everything to keep it balanced.

 

I've made it so it fits a guitar neck as well, so there's two clamps on the drill. This is a broken Squier neck from something. It appears that somebody drilled through the neck and out through the fretboard (wasn't me). Using this as a test to learn from. 

 

 

This is the 5mm drill and the laser guidance. I know the depth is 18mm as I already tested it.

 

 

First 5mm dowel

 

 

And all four done

 

 

The lesson to learn here is don;t make the dowels too short

 

First drills done.

 

 

Drill, glued and inserted.

 

 

Now we leave it for 24 hours to dry.

 

I'll probably cut the dowels with a Dremel and then file down the tops by hand (carefully).

 

Rob

 

[rwillett]

All the dowels are now sanded down and flush with the heal. I had to slightly tile away some of the varnish to get it flat. I did as little as I could but it is is what it is. I made a little drill centering tool that fitted through the body and made small pilot holes for the proper holes to be put in. You will note the holes are about 2.5mm out from the originals, so close but so far.

 

 

 

Looking through my spares box, I have a number of screws I can use, these are 45mm long, thought the screw body is really 43mm as the head can't be counted. 

 

 

The heal in the body is 27mm thick, which leaves 16mm of thread into the neck. However there is no ferrule in this measurement or plate (not that I have a plate the fits).

 

If I put a ferrule on the back, then the screw left to go into the neck is 12mm which really doesn't look a lot to me.

 

Should I try and find longer screws or is it OK to use the screw without as plate or ferrule?  Looking through Basschat @PaulThePlug seems to have had the same issue.  

 

I think I'll find some nice 50mm ones and use a ferrule unless somebody has a clever idea.

 

Rob

 

[JohnH89]

4.5 x 45mm screws every time for me . Straight through the neck plate . Never had a neck fall off yet Rob .

Edited Tuesday at 18:00 by JohnH89

[rwillett]

@JohnH89 

 

I don;t have a neck plate, so am using a ferule so I'm losing quite a lot of thread and that worries me. 

 

I can try it and see what happens but I am slightly nervous

 

Rob

[PaulThePlug]

Mine has been fine...

By using the ferrules CSK in to the body, you are?gaining a bit in to the neck...

Or go for the Bolt and Threaded Neck Inserts - but looking at them, after the taper in, threaded element looks about 6 - 8mm, or the thickness of a machine nut.

 

Edited Tuesday at 18:45 by PaulThePlug

[tauzero]

I use bolts and threaded inserts, they work very well.

 

Alternatively, with your pillar drill for accuracy, you could recess the ferrules into the body, giving you an extra ferrule's thickness of thread in the neck. Or buy longer screws, you cheapskate.

[Geek99]

On 10/06/2025 at 18:46, rwillett said:

All the dowels are now sanded down and flush with the heal. I had to slightly tile away some of the varnish to get it flat. I did as little as I could but it is is what it is. I made a little drill centering tool that fitted through the body and made small pilot holes for the proper holes to be put in. You will note the holes are about 2.5mm out from the originals, so close but so far.

 

 

 

Looking through my spares box, I have a number of screws I can use, these are 45mm long, thought the screw body is really 43mm as the head can't be counted. 

 

 

The heal in the body is 27mm thick, which leaves 16mm of thread into the neck. However there is no ferrule in this measurement or plate (not that I have a plate the fits).

 

If I put a ferrule on the back, then the screw left to go into the neck is 12mm which really doesn't look a lot to me.

 

Should I try and find longer screws or is it OK to use the screw without as plate or ferrule?  Looking through Basschat @PaulThePlug seems to have had the same issue.  

 

I think I'll find some nice 50mm ones and use a ferrule unless somebody has a clever idea.

 

Rob

 

I have a F plate spare … 

[Geek99]

On 10/06/2025 at 19:09, rwillett said:

@JohnH89 

 

I don;t have a neck plate, so am using a ferule so I'm losing quite a lot of thread and that worries me. 

 

I can try it and see what happens but I am slightly nervous

 

Rob

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