Need help, my first build has some issues...

[Camarillo]

Hello guys
hope it's the right place for this thread...
I just finish my first build. A PJ with spare parts bought in several months, from different places, added to some hardware I already had: 2 leftover pickups for other upgrades, a bridge.
Despite the difficult (for me) wiring I chose (a concentric know VT/VT in the style of the 60s J) the instrument is done, it makes sounds. It's alive but not kickin'.
I have a couple of issues and I need your help to try to fix them. At this point I don't want to give up and brought it to a luthier for the fix.
All the issues are related to "height".

• The pickups are too low. I had a "sponge" with springs under the pikups, but they barely reach out from the pickguard. I think the hole is too deep. Is there a standard measure for those?
• At the low pickups sum very high strings. I had to set the bridge saddles very high to make the play without buzzing. I measured the heel of the neck and it's about 25mm which I think it's fine. Could it be the the pocket of the body it's not deep enough? Again, what's the standard measure for hosting fender style necks? What tool should I possibly use?

Those are the main problems. The a couple of quite easy fixes.

• the concentric knobs I got are not moving separately. The pots are CTS I had on another J bass, and it's quality stuff. If you guys have some models/brands to suggest I would appriciate.
• the nut of the chinese neck is a crappy peace of black plastic. I never changed a nut, but I should be able to do it.

Below some pics.

 

[bobdabilder]

Neck pocket should be 5/8 inch deep and I use 5/8 also for pickup routs.

 

[Lownote38]

The top knob is probably rubbing the bottom knob which causes them to both move when you turn one of them. Loosen the top portion, lift it up a bit, and tighten it back on. That should free them up.

 

[dwizum]

If your pickups won't go high enough, either add more foam, stiffer foam, or wood shims under the foam.

Your action problem - needing the saddles very high - indicates that you need a neck shim. Neck shims are used to fix issues with the action being out of bounds of the saddle adjustment range. If the saddles can't go high enough, you need a reverse shim, ie one that's thicker near the headstock end of the neck pocket.

I would solve the neck shim problem first, then re-check pickup height. Using a shim will allow you to bring the strings closer to the body and you may find that the foam you have under the pickups is still enough to allow correct adjustment.

 

[Turnaround]

There look to be a number of problems with your bass. First, the strings seem very high, but you say they must be high to avoid buzz. Something's wrong and it could be improper relief, unlevel frets or bad neck geometry.

Second, the nut needs to be trimmed- it's too wide.

The string hold down is pulling the A string out of alignment. Are you sure it is installed correctly?

You need to realign the neck - it is shifted toward the G string side. The pickup needs thicker or more substantial foam under it.