EX-4 Bass First Build

It finally arrived!
https://i.imgur.com/XVV3ZnR.jpg

Here are the specs, customizations, and planned upgrades:

BODY
Explorer Style
Alder
No bridge holes drilled
Musicman pickup route (this was messed up at the factory, got a humbucker in the wrong position)

NECK
Medium Scale (32")
Maple fretboard
Black dot inlay (painted on though... kind of disappointing)
Explorer headstock (modifying the shape to look more like the Fernandes BXB headstock)

Hardware
Fender style bridge (probably the Gotoh 201b-4)
Stock tuners (i'll possibly upgrade but not a top priority)
Bone nut? (probably should have just added that on to the order but totally forgot)

Electronics
Nordstrand MM4.4 Quad Coil pickup
3-way rotary switch for series, parallel, and "single" coil
Tone 250k audio w/ 1uF cap
Volume 500k linear

My first big mission is to plug that humbucker cavity. Pitbull was great and sent along some scrap basswood to help with that (they didn't have any alder).

I've read that lots of people use bondo to fill in any gaps and make it smooth but I'm worried that since the plug is a different wood than the body that over time you'll be able to see the outline. Am I being too paranoid about that or is there a better method that allows for more natural "breathing"?

The painted dots look great under clear coat , don’t worry
When I built my Frankenstein copy (in signature) I used scrap timber and builders bog to fill the humbucker holes, 3 years and no cracks. I’d say the bonding of the bog and the size of timber slab would keep it still enough, the hole is centre of block

I've used basswood to plug up the ends of a pickup rout in a JB kit as the pickups I'm using are shorter but wider than the standard JB pickups. I used Titebond to glue it in place, then filled the gaps with an UV-curing resin. Then sanded the top flat and routed out to the right size. With primer and paint on top, you'd never know.

Wood doesn't breathe, but it can dry out or absorb moisture, which is one good reason for putting a finish on the guitar, to prevent this happening as much as possible and stop it shrinking or expanding slightly with changes in climate conditions.

I've never used Bondo itself, but I've used similar products for filling and you should be fine with it.

Great to know about the painted dots, now I won't be tempted to do something dumb that might mess up the neck :P

Thanks for the reassurance about plugging the pickup cavity, that hole will be a distant memory in no time!


Headstock Update
I wanted to mirror the lines in the body a little more and get away from the hockey stick aesthetic!

http://i.imgur.com/myVU181l.jpg

https://i.imgur.com/PvaJv1W.jpg?1
https://i.imgur.com/nHOWDmE.jpg

To fill the humbucker cavity I sanded down a chunk of basswood until it just barely slid in without any force. I glued it in place with Titebod, followed by LiquidWood epoxy to fill in the gaps. I finished it off with Minwax High Performance Wood Filler (basically Bondo). Then I went over the whole body with 120 grit sandpaper to smooth out the plug and get out any scuffs and dings from the factory/shipping process.

The neck heel and the pocket didn't use the same radius corners so I ended up sanding down the heel to make it fit better. There is still a very very small gap under the fretboard where the heel meets the body. When I firmly push the neck towards the bridge it feels solid, but if I move the neck even slightly up or down (maybe towards or away is more accurate?) there is some play there. I'm not sure how to decide if I need to do more or if I should leave well enough alone.

Quote:

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Originally Posted by starsloth

The neck heel and the pocket didn't use the same radius corners so I ended up sanding down the heel to make it fit better. There is still a very very small gap under the fretboard where the heel meets the body. When I firmly push the neck towards the bridge it feels solid, but if I move the neck even slightly up or down (maybe towards or away is more accurate?) there is some play there. I'm not sure how to decide if I need to do more or if I should leave well enough alone.

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Yeh, the neck pocket has the radius of the router bit, and the corners of the neck heel appear to have been done with a belt. I also had to work on the corners to get a better fit. The problem I then had was that there was some side to side play with the sides of the neck route being parallel and the neck heel sides being tapered following the fretboard. The gap was small, but I ended up sanding some veneer down and shimming the sides.

Remember that the size of the pocket gap will be reduced when you put finish on the neck. You don't want too tight a fit when it's unfinished for that reason. But you may have a slight gap at the end of it all. If the neck's pushed over to one side so that's the total gap, then I wouldn't worry about it. It looks to me like you won't have enough of a gap to shim and still have room for finish.

Are you planning to paint or clear coat the neck?

Planning on tru-oil for the neck

I’m less worried about the side gaps (my fender zone’s neck heel is totally exposed on one side!). My concern is that when I go to bolt the neck on it will be a little askew. I’m just not sure how to make sure it’s perfectly squared up with the side to side wiggle I’ve got going on!

You’ve got the strings to guide you. Get them running parallel to the sides of the neck and you’ll be fine. It can pay to have a small amount of side to side movement available to get that adjustment, just in case the bridge goes on a mm or so out.

I finally figured out how to establish the true center line! It seems so obvious now haha

In case someone else needs the process here’s how I did it:

1) clamp the neck in place with enough space to fit your straight edge between the side of the neck heel and the clamp

2) line up the straight edge firmly against the heel and draw out that line across the body. Do this for both the top and the bottom of the heel

3) pick a fret and using a ruler or measuring tape, start at the center of that fret and make 3 or more points at set distances along both the top and bottom lines (5”, 8”, and 12” for example)

4) measure the width between each of the corresponding points and make a mark at the halfway point

5) make a line connecting all the halfway points and you’ve got yourself a center line!

New pickup cavity!!

https://i.imgur.com/neClCWm.jpg
https://i.imgur.com/ivwbDVe.jpg?1
https://i.imgur.com/3h025C9.jpg
https://i.imgur.com/Vvswig6.jpg?1
https://i.imgur.com/HPyYNKs.jpg

I've never done any routing before... I was able to get a decent used plunge router for about $20 which worked great. Made the template out of some left over maple flooring which was nice cause then it was long enough that I could clamp the template and body to the table with enough room for the router to maneuver.

Since I was new to the process I left myself with about 1/8" all around from the final dimensions. This proved to be a very time consuming decision... so. much. sanding. It all worked out well though and the pickup fits in like a glove.

That being said, I had read that people liked to make the depth of the route about 1/8" shallower than the pickup itself. What I didn't take into consideration were the wires attached to the bottom of the pickup that measure about 1/8"... I decided to just notch out some extra space in the bottom of the cavity. It works, but looks pretty janky. I'm debating if it's better to reattach the template and route the whole thing down a little more.

Drilling the hole from the pickup cavity to control cavity was the scariest part of this journey so far. I didn't have a very long bit that was the right diameter and I didn't really know how to even begin figuring out the right angle either. So I just freestyled the angle and hoped my bit would be long enough. Thankfully it all worked out!

I could use some wiring help

https://i.imgur.com/9ZoduIo.jpg
https://i.imgur.com/L32haE5.jpg

I really wasn't sure exactly what I needed for a rotary switch, but I got one that is 3 poles 3 positions. One position for series, one for parallel, and one for single coil.

I've done wiring before and understand some basics, but to a large extent, it's still a foreign language and wrapping my head around the rotary switch has been a challenge. I maybe have it worked out, but I am not confident at all. I think I've come to realize I only needed 2 poles, but since I had 3 to work with I decided to try and utilize it for the ground.

I made a diagram and listed out what the wire combinations need to be at each position. If someone with knowledge of this stuff could let me know if my diagram will work or not that would be super amazing!

All looks fine to me. Well done. Good in my book to get the output lead in a channel like that to keep it out of the way and in a known place so it can't interfere with the pickup mounting. You won't see it, so unless you really have to deepen the pocket, I'd leave it as is.

Not sure If you're planning to direct mount hard to the wood, or use some foam rubber or springs for pickup height adjustment. If so you'll need some room for those to fit work, though a 1/8" thin strip of hard foam either side of the output wire could be enough, depending how high the strings end up from the body. If springs, you could drill out deeper sprig-diameter holes at the screw locations to fit some springs in and not have cut-down springs that end up fully compressed.

Thanks for the quick feedback!

I don't have a preference for the pickup height adjustment mechanism. What do people typically find works the best? Bonus if it happens to be the easiest :P

A hardish foam is the standard. Pickups like that normally come with a bit of self-adhesive foam. I normally cut it down and use smaller pieces rather than use it a single block as they squash more easily, and you can also position the pieces to avoid the pickup lead.

Your position certainly 3 doesn't work ATM. You've got two output wires going to hot and nothing to ground. And you always want the shield going to ground, so I wouldn't have that anywhere near the switch.

I'll have a look at the pickup wiring diagram when I have the chance and check the colours etc. before I can check the other connections.

You’re absolutely right that the shield should be connected to the grounding pole in the 3rd position, good catch!

The wiring guide I have in the upper right of the diagram is copied from the instructions that came with the pickup. I followed that a little too closely I think.

(3) would be better written as connect red, white and black to hot, green to ground.

Black and white are the ends of one coil, red and green the other. You'd normally connect the middle pair of wires (red and white) to ground (as well as green) to split the coil, but as you want the other coil as the single coil selection, they are connecting both ends of the black/white coil together, so that coil generates no output, but both are connected to the 'hot' signal connection, as is the red wire, so the red/green coil is the one providing the output.

If you write their connections out fully, you'll see that the black wire is always connected to the hot signal connection, and the green and shield are always connected to ground. So there is no need to switch those at all. It's just the white and the red wires that get switched. It's best to keep things as simple as possible and not introduce unnecessary switching.

I would have done things differently on the single coil selection as I prefer to keep unused coils grounded, to prevent them injecting noise into the output signal (I'm not sure if this is possible or not, but I prefer to play safe) and so (3) would become:
Red - hot
Green, white, black, shield - ground.
Then there is no risk of any extra noise from the unused coil.

Thanks for all the great info Simon!

I’m pretty sure I follow and I’ll update the diagram and add in the tone, volume and output jack now that I know I’m somewhat on the right path for the switch!

For (3) though, shouldn’t both red and white still be hot? Then green, black and shield to ground.

And for the (1) series position, should red and white being going to ground?