As part of the 'try something different' aspect of this build I wanted to see if I could cut a nice low nut for it without having the strings on, without the bridge on, without even the neck on the body. Basically, can I make a decent bone nut that won't really need adjustment using just the neck as a guide.
I didn't want to waste a good chunk of bone so I dug out a blank that was borderline too small. It was thinner (towards the headstock) than I'd like, but if things went right it should just be big enough.
The plan was to use the 'clearance over 1st fret' as a guide for cutting the nut. Normally, fretting a string at the 3rd fret allows you to check the clearance above the 1st fret. In this case I used a short thin straight edge sitting on the crown of the 2nd fret to the string slots on the stock nut (sitting in place) to get an idea. It was actually closer than I expected, but a little high, so I transferred slightly lower measurements of the E and G to my nut blank and drew a 12" radius between them. Then marked out the string spacing.
Rough shaped the nut and slots cut slightly short of their intended depth. I much prefer the single size black handled flat nut files, they're easier to use and have a better cut, but I had to resort to the larger two-size edges one for the 105 E string. Cut as 046, 065, 085, and 105 and using the stock strings to how they sit in the slots.
Some final tweaks, sand and light polish. Looks ok but won't know if it's good enough until I actually get to assemble the Bad Girl.
Black nut is a long way from home…
Given that the build will have black hardware and a dark fretboard a pale bone coloured nut won't really match, so time to see how well bone takes stain. I didn't want to immerse it in any stain to thoroughly soak it for fear of the bone being weakened, so I decided to try the Fiebings once again (with my favourite type of Fiebings applicator).
It didn't take much stain with each coat, but eventually it started to darken the way I wanted.
To answer your question BassGuy...
Electrickery.
While the nut is staining and the Tru-Oil on the body and neck is hardening it was time to get to the heart of this build… the wiring.
The idea was to test a few things for future builds, but also to make a versatile bass with a wide range of sounds. It's a P J bass so there's always a compromise between the potentially noisy single coil J bridge pup and mostly hum-free split coil P neck pickup. The four switch block in the back of the control cavity shown at the start of this thread is only part of the grand scheme, the circuit also needs a couple of push/pulls and a balance pot. The switching plan is this:
- Master Volume Push/Pull switches the P pickup coils from series (standard) to parallel.
- Master Tone Push/Pull selects between two different tone capacitors.
- 2 x mini DPDT slide switches allowing individual phase reversal of each P coil.
- 3PDT slide switch that changes the connection between the P and J pickups from parallel (standard) to series.
- DP3T slide switch that provides Treble cut/Normal/Bass cut settings.
- Balance/Fade pot, works as a balance when pickups are linked in parallel, works as fade/bypass in series setting.
Here's the diagram I came up with:
Level of soldering difficulty: Over 9000
Lots of different switches and settings, but the two main ones I wanted to test were the Parallel/Series switch between the pickups and how the balance pot function changes with that setting. And, the Treble/Bass cut filter switch.
Balance pots have their draw backs, particularly with potential treble loss, but I needed one in this circuit. When the pickups are linked in parallel it works as a standard balance pot: centre detent is full volume on both pups, turning it to the side reduces the volume of one pickup or the other. With the link switch in series mode it changes function and instead controls how much of the signal goes through each pickup and how much bypasses it, sort of like a Dano circuit.
The filter switch uses a single cap to manipulate the signal. In the centre position it's normal, no effect. In the up position the cap filters of the high frequencies to ground, like a mild tone control on full. In the down position the cap allows the highs through the circuit but drops out some of the bass, like the Strangle switch on a Bass VI. At least, that's the plan.
First step, lay out the parts and test them/check their values. In this case my 0.0047 filter cap was wildly above the range I wanted, as were all the others from that pack (all .0054+)t, so I eventually found an 0.0033uf that measured in at 0.0046uF. Perfect!
Due to the potential complexity of the wiring, especially in the tiny little control cavity, I didn't want to have to pull it all apart if I ever wanted to change out the pickups. So, I cut two small pieces of Veroboard that will sit in the pup routs to act as links between the pickups as the wiring loom. Then it should be easy to swap them out if needed.
Yes, I know, I could have got quick connect plugs.
One unforeseen, but should have been seen, obstacle was that the fat shielded 4-conductor wire that I needed to run to the P pickup rout was going to be too big to fit through the hole to the control cavity along with the bridge pup wiring. So a little delicate enlargement was required. I had thinner 4-conductor wire but was too stubborn to use it.
Just trying to squeeze the two large Orange Drops (0.047uF and 0.068uF) into the control cavity without interfering with anything else was going to be tough, I still wasn't sure if it was all going to fit.
I'm using 500K pots in the circuit, rather than 250K's like in a J bass, but decided to include a treble bleed to help with potential unintended treble loss. 0.001uF cap and 150K resistor.
Because there are so many connections between the pots and the switch block (11), plus the extra 4-conductor wire to the P pickup, I decided to use some ribbon cable to try to make it a little more manageable. Trying to solder the connections on the mini DPDT's with everything else in the way was challenging. One of the mini DPDT's actually sprung apart while I was working on it… much rage while I reassembled it. But, eventually I seemed to have everything connected correctly… maybe.
Now I need somewhere to put it.
Shielding.
As a cheat I used my routing templates to get the basic outline for the shielding tape.
Press into shape with the backing still on whenever possible.
Single piece in the base of each section, and then a single strip completing the sides of each cavity with overlap.
At this point the finish on the body had been hardening for two weeks, so it was time for a light white spirits wet sand and then a gentle cut and polish. It needed to be done now before moving on to the next steps.
Ground wire linking the shielding in each cavity soldered in place, and solder joins added to ensure connectivity between each section of copper tape. Bridge ground wire looped and temporarily held in place with a copper tape scrap while the other end is permanently soldered to the shielding link wire in the bridge pup rout.
Shielding ground wire soldered to control cavity shielding as well and ready to connect to the actual circuit. Note: I've added some small pieces of grey duct tape to the base of the cavity where the underside of the lugs for each pot will sit. I need the pots to sit as low as possible in the cavity and the tape helps to ensure that the lugs can't short out on the copper shielding.
As an added precaution I put some heatshrink over the tip arm of jack, this prevents it from shorting out on the copper shielding as can easily happen in a tight cavity when using an Electrosocket type mount.
It was time to see if all my wiring would actually fit as intended. It was a very tight fit and took a bit of coaxing but eventually it all squeezed in… just.
To make the circuit work I needed access to the individual coils of the P pickup… which meant cutting the coil link wire, not something you normally do. I'm actually using GFS pups in this build.
Snip.
Adding the Veroboard link for the P pickup. The large piece of heatshrink on the wire will slide over the board once the pup is connected.
Time to finish up the neck. First, some waxy love for the fretboard. It takes some time to get the wax to the right consistency and a fair bit of effort for the rub on, rub off, but good results when it's done.
Wax just applied.
Once that was done I gave the neck a light cut and polish, just like the body. One unsettling discovery while polishing the headstock face was that the epoxy inlay takes on heat really quickly. The surrounding wood was completely cool yet the inlay was warm to the touch which is a little concerning. If it ever got too hot it may start to crack your finish. High-end marine epoxy etc. may be more stable, but just be aware if you ever decide to try it.
I gave the blackened nut a wax too (I was going to make a waxing my nuts joke, but probably best not).
The neck all dressed up and ready to attach.
Neck, meet Body.
Assembled and ready for her strings and finer things. I decided to go with the riser plate for the bridge, it looked like it would be borderline too high but I wanted to give it a try first.
As soon as I had the strings on it was clear that I'd eventually need to drop the saddles a little lower, so I took the strings off and removed the bridge riser. A day later with the neck relief tweaked, intonation set, and some saddle height tweaks the action was looking pretty good. I think it may even safely go a touch lower.
As far as my 'pre-emptive make a nut' effort went… better than I expected. The E is pretty much as low as you could hope for, A and D could maybe come down a hair and the G is probably half a hair lower than I'd want. But, I'm pleased it's as close as it is.
Finished
As always seems to be the case, I've found it almost impossible to take photos that convey the colours and depth of the finish etc. But, I figure if I take enough pics in enough places some will eventually show what it really looks like, so here goes…
Ok, no more, I promise. There has to be a couple of good ones in all that.
Anyway, she a Bad Girl and I'm pretty pleased with her. I'm still experimenting will all the sounds but it seems to work as intended. The series pickups setting gives a powerful dirty sound, which can be mellowed with phase changes on the P coils or flipping them to parallel. The filter switch gives a nice punchy sound with the bass cut while the treble cut knocks off some highs nicely. At least, to me. But, it's early days, I'm in no way competent to judge a bass in any respect.
Now, back to my other builds… and yes Wokks, the Telebilly has started to progress again (sort of).
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