Your truss rod is probably fine, you just need the right wrench. Looking at your pic, my guess is 4mm.
Also, some truss rod nuts have a round section before the hex section and it can feel like the wrench is in but it really isn’t. I couldn’t find a good pic to show you what I mean but this is close…
Thanks for your input, @Korrigan, much appreciated!
How are your projects coming along? Chapman Stick, anyone??? 
No basses lately but I just finished a 4 string fretless slide guitar.
If the strings were a little thicker… 
it could be described as a short scale fretless picollo bass 
I like it a lot anyway, the headstock shape is pretty cool !
That’s exactly what it is @terb! 
And thanks, that’s my signature headstock shape… the only problem is that, because I make them by hand, no two are ever exactly the same shape. lol
not a problem in my opinion, it’s a distinctive sign that it’s made by hand, one by one ! by the way the plate is very cool and original, it’s a nice idea 
Absolutely the best ‘how to adjust your truss-rod’ video I’ve come across. Just thought I’d share in case it’s useful to somebody. https://www.youtube.com/watch?v=cgmoRHr2cD8
Also @Korrigan, that tip about angled p-bass pickups; mind blown!
Anyways, I could use a little advice. Following some diy fret leveling I’ve got a buzz on the E string, only when the 6th fret is fretted but the buzz is coming from the part of the string between the nut and 6th fret, not from the ringing part. (Am I making sense?)
I’ve never come across this before.
Does that sound like more banana is needed via the truss-rod, or something else?
Wow that’s weird. No idea. Does it stop if you apply a lot of fretting pressure?
It does stop if I apply an unnatural amount of fret pressure, or if I press more over the fret than behind it (but that mutes the note slightly), or if I also touch the string behind the fret with another finger (but can’t always do that).
Have you tried to see whether fretwraps could alleviate the situation to some extent?? Even just an “improvised” one, like a hair scrunchy…
is it possible one of the frets behind it are too high?
I think it is that, my fret leveling job was likely not perfect but it’ll do for now.
In the end I tweaked the truss-rod with as little a turn as I could. Seems fine now. I think I was avoiding the truss-rod because I’d done all the other adjustments and didn’t want to go back for more.
It’ll do for now anyway and is a big improvement over the sky-high action and a few dead frets!
Also, funny story; this bass hummed really loudly. When I went to adjust the pickups I found one side wouldn’t move. Took the pickup out and found the spring wedged under the pickup and stuck to the magnet. With the spring back on the adjustment screw; no hum! 
Hello y’all!
A question about measuring the fretboard radius while doing the setup.
How important is that?
Since it is mostly suggested to setup the action height (bridge saddles) according to your own feel and even the most clicked setup videos on YT do not use the radius gauge, why is it something that we should consider?
Also for string change most simply seem to cut off all the strings and then change them all together meanwhile a TB instructional video was suggesting to change them one a time if possible so it does not instantly relieve tension from the neck causing the wood to move too much all of a sudden…
I can see that it is a good opportunity to clean and oil the fret board but my bass is still super new!
I’ve always taken all my strings off. Lets you nicely rub the fretboard with a cloth, oil it if you want, etc. Also, buff the frets.
After each playing I usually run a microfiber cloth between strings and fretboard, like a lot of people do, but having the strings off is nicer for any real cleaning or polishing.
As for a radius gauge, never bothered at all, I just set the string individual heights to feel good to me and only buzz if I dig in.
I wouldn’t cut the strings of. You can clean them by boiling them. So it is possible to reuse old strings. They will not be new, but most of the sweat and dirt will get removed.
I’ve never done it (not playing for long enough), but I’ve heard that it is possible to do.
Well my strings are the ones the bass arrived with about 2 weeks ago and I have been cleaning them every two days. However the bass was almost in tune when it arrived so they were remained under tension for who knows how long…
I also think to keep them however if I need the dull thud and incase the 45-100 gauge goes too wrong…
I have received the D’addario 45-100 Nickel Roundwounds. Can’t wait to go home and put them on…
I will remove all strings (without cutting them) and clean the fret board real nice. How ever I don’t have any products specifically for this. Any homemade products I can use without damaging? Like pure olive oil and vinegar (Living in Italy hehe) ?
Cleaning the fretboard will depend on the wood and most importantly whether it is sealed or not. it’s best to look up some cleaning tips specific to the tpye of wood used. Better no hasty choices you might regret
I have never cleaned a fretboard yet, but have looked at the information that’s around, much of it conflicts.
Think it does depend on the wood on the fretboard.
One thing that I’ve seen a few times online is warnings like this:
“Olive oil , or any other vegetable-based oil , is not recommended for oiling any wood as it may go bad, or rancid, after a while. Most commercially available fretboard oils use mineral oil as their main ingredient. Mineral oil is inexpensive, will not go bad”
