Cut It Out!

Before the neck and body get joined together I need to make some space for the circuit board, switches, voulme pots and batteries. I started by drawing out the shape of the covers on paper making sure they will fit in the little space there is left. The covers were then fashioned out of brass plate and could then be used as templates to mark the wood. The first one to try was the space for the PCB, and it is going to have to live in the upper horn. This is as far away from the pickups as I can reasonably manage to keep any interference noise to a minimum.







The controls for the animation are also in the top part of the guitar and are going to be inside the top cutout. This leaves the guitar with fairly clean lines and the minimum of clutter (unlike my Vigier!). There is a toggle switch (Bright/Off/Dim) and a push button (Animated/Static) which are usefully placed to my mind.



On the lower half of the guitar the pickup wires will eventually be routed to a pair of volume controls and the mother of all switches. This toggle switch took a while to track down and is a 4-pole, 3-position, on-on-on switch. In short, I can wire the switch so that I can have the coils from each pickup in series, parallel or just a single coil. This gives some variation in the tone, whilst keeping the controls simple. I don't want it to become too complicated...





Once the switching and volumes have been taken care of, the signal is routed to a 1/4" jack socket. I am using a Neutrik socket as they are really well put together. The hole for this was bored using a hand brace and bit. The recess for the mounting flange was chiselled out and the fixing holes drilled, as well as a connecting hole between the back of the socket and the volume / switch area.




The neck is still being built up. The carbon rods have been stuck in with epoxy resin. I didn't think that wood glue was going to do much with carbon! After them, the LEDs fitted onto veroboard were tacked into place with a dot of superglue and the fboard tentatively placed on to check the alignment. A amount of adjustment was required and then this was bonded into place with wood glue, contact adhesive and superglue (mostly due to me hedging my bets on what is going to work best!). This needs to be thoroughly set before I verify the LEDs are working and then it will be ready for the fboard to be stuck on.

Trust Rod Fitting

Now is the time to fit the truss rod (or trust rod, which I feel is more apt, as I am really hoping it is going to work!). The aluminium anchor piece needs to sit under the fboard near the headstock. A hole was chiselled out for it carefully. I have to remember that the neck will be shaped later, and that getting carried away with chiselling could result in a weak end, which is the sort of thing to be avoided at all costs.

The anchor piece slots in OK.

The same sort of thing was done for the adjustment end. This one had to be done even more carefully as it will be visible after the fboard is stuck on. A couple of 30mm screws hold in the nylon bearing block. This had to be penned black as it too will be just about visible. The trust rod was covered with some 6mm heatshrink sleeving and a little oil before it was commited into the chamber of doom, er, the truss rod channel.

Everything was checked & double checked and then it was time to fit the wooden fillet that has a curve that matches that of the (chamber of doom) channel. Lots of glue and clamps as per usual.

Put to one side and allow to dry - and here's one I made earlier. Aaah a Blue Peter dream sequence!

When the glue had dried, I cautiously wound up the tension, looking for a bit of backwards curving. Disaster! As I wound the tension up, the neck started to show a small amount of forwards bow, ie in the same way that would be caused by a set of strings.

Smeg!

Due to the amount of tension I put on the neck, the anchor piece had also started to migrate south for the winter. Whilst I puzzled over what seemed to be a loophole in the laws of physics, I thought I had better strengthen the anchor piece to neck connection with some additional blocks of wenge. This meant losing a small amount of the channel intended for the carbon stiffening rods, but this was more essential. Some M5 washers were also 'drifted' into place just to help out.

Well, here's my theory. Ahem.

The neck currently is not shaped, it has a rectangular cross section. Because of the amount of channels cut into the top, the absence of the fboard and the extra thickness and girth of the neck it is not only much stiffer than a standard neck, but the stiffness is predominantly underneath the trust rod. When the rod is tensioned, although the curved channel should cause a backbow, at the present time with the greatly increased rigidity of the material under the rod, the top of the neck is more likely to be compressed causing a forwards bow.

This seems to make sense, but I cannot do much about proving it until the neck is a lot closer to being finished (ie back coarsely shaped, fboard stuck on). This is another reason why we all have to Trust In Rod.

Go Naked

Looking at the size of the veroboard layout for the MoonBassAlpha animation circuitry and then looking at all the cutouts that I have made in the body, I soon realised that there was nowhere for the electronics to live. A PCB needed to be knocked up to keep the size as small as was practical. The board was designed using CADStar, which is too powerful for its own good and will let you to make quite fundamental errors if you wish. I finished the board off with my customary "its close enough for jazz" air of carefulness...

I was tipped off about a local PCB manufacturing company Spirit Circuits who offer a cracking free PCB service! I am sure it is for legitimate prototype work where they hope to get repeat business rather than homers, but I'll just have to placate them over the coming months. The idea is that they supply a one-off board with the copper tracks and drilled holes, but without any silkscreen legends or solder resist mask. This is why they call it "Go Naked".




The finished board looks a bit lost in their A4 paper sized panel. Once it is cut out then construction can begin. The smaller parts are placed first and it soon becomes apparent that fine surface mount parts on a board with a ground plane really does need solder resist. It is quite tricky to avoid shorting things out with only a 10thou gap.



After the small stuff, the meter was brought out to verify that there were no short circuits and then the larger parts were slapped on. I mananged to incorporate a few cock-ups into the board design (no surprise there) which required one or two upside-down components and a couple of after-thoughts tacked on in precarious places.

The board was ready to try out and I needed to see how noisy it was going to be. Very few guitars have animated fboards, and probably even fewer have switch-mode power converters to power them. The lights take around 100mA from a 5V supply and running this from a 9V battery would make it a rather short-lived affair. Much higher capacity can be found from AA rechargeable batteries, so the MAX856 converter takes this 2.4V and changes it to either 5V or 3.3V (which gives a neat choice of brightness levels).




After a few more modifications, the board is not putting out too much noise. It needs to be kept away from the pick-ups as far as possible, (distance helps) and 3V3 operation is much quieter than 5V. All-in-all the amount of buzzing and whistling that makes it to the pick-ups is pretty small, and won't be noticed when everyone's playing. For recording use, I could just turn the lights off...


The Trust Rod Ends

At last the rod ends have been finished. Many Thanks to Keith at Eaton for knocking the brass adjuster up in his, er, lunchhour. This really looks good and will be seen somewhere at the end of the fboard once I channel out a place for it to fit into. It is going to run in a nylon block. This should spread some of the compressive force back into the wood and turn more smoothly than just a manky old washer alone.

The thread gets a bit tight in the middle - possibly it was tapped from both sides and didn't meet exactly, so I need to drill part of the thread out from the large end. It will still have a good 12mm of thread remaining.

The adjuster is based on the ones used in the Ernie Ball MusicMan range of basses. This seemed a much more elegant way of adjusting the rod instead of trying to find a hex-key down a tunnel like most guitars. I couldn't find one off-the-shelf at the time though I am sure somebody makes them somewhere.



The other end of the rod has got to be anchored into place (somewhere under the first fret or thereabouts) with this interesting shaped piece of aluminium fashioned by me using the milling machine at work. Hmm - functional, but it is probably just as well it won't be on display.



I hope all this fits...

Shaping The Body With Chiselled Features

The plan view of the guitar was as far as I had really got with my full sized sketches - I am not known for possessing any great depth. To carry on the fish pretzel theme that I started on the headstock, I want the body wood to look a bit organic, to flow and overlap rather than just sit there and look heavy and cumbersome. So this requires a fair bit of wood removal to make it happen.




At first the router was used. This is great for removing material, but in this case is self-defeating. After a while, all the flat surfaces that the router needs to sit on have been buzzed away, leaving a choice of it sitting on precarious 'islands' of the original height, or freeform use. Hmm, sounds like a trip to A+E is only seconds away if I try that too often, so it is back to the manual methods after this brief flirtation with power tools.




Chisel! The word sounds a misleading - like a chisel is used to stab at the wood and rip a bit out. With a decent (and sharp) chisel the ash can be worked with a bit of effort. Ash has a large grain pattern and it seems to change from quite easily workable in some parts and really hard in others. This takes some getting used to, but understanding this helps to work with the wood and not against it. I had to keep sharpening the chisel on an oilstone throughout the shaping.





Between major bouts of chiselage (what a good word - I wonder if it exists?) sanding the contours with a block helps to blend the shaping into pleasant curves.

There are a few places on the body, inside the teardrop shaped cutouts, where it is difficult to work on. This could be why nobody else makes a guitar body that looks like this?




Here's the body parts pushed back onto the neck. All the shaping and radiusing apart from the the initial rough router work has all been done by hand (and aren't those hands feeling sore!). The top has been shaped so that my forearm will have a nice resting spot. From the front the central walnut stripe is just about visible.

The truss rod channel and positions for the fboard lights are just visible further up the neck, at 3rd and 12th fret positions.

It isn't easy to see in the photo, but there is still a way to go. The body is still proud of the neck in places, and the bottom of the guitar needs to end in a curve (the neck is just sawn at an angle at the moment).

The next step is to think about where I place two volume pots, a 4-pole pickup selector switch, the 1/4" jack socket, the pacman leds on/off switch & select button, the pacman led circuit board and the batteries. No problem, I'll put it all in one of the holes...

Stripping In The Blue Light District

The Ibanez body is quite a dark brown color. I thought it was a solid paint finish for many years, but if you take a fresh look there is definitely a decent bit of woodgrain going on underneath a heavy lacquer.

The bass is a lawsuit model dating from the mid-seventies and has had some remedial work carried out already. The original Gibson three-post style bridge was replaced (quite rightly) and a thumbrest was ditched. The holes left were filled with wooden plugs and under the dark lacquer the repair work was practically invisible. The bizarre shaped cutout that looks ideal for storing ice-lollies was hidden away under a scratchplate.







Half way through the paint stripping and Chewie & me are wondering if perhaps we have been a little bit hasty. It is looking quite rough now. Talking about different new paint finishes keeps us going...



Once the paint stripper has done its chemical nastiness, we attacked the surface with sandpaper. It was like trying to sand glass. At this stage other uses for the body were found, such as the latest in guitar-inspired lingerie...






It took power tools and some good old fashioned grunt to shift whatever was still clinging to the wood, but evetually the mist started to clear. The paintjob had been hiding quite a nice veneer. The body could now be seen properly and was constructed from five layers of differing thickness hardwood (plus two [ash?] veneers), with the grain direction changed on alternate layers. With the contouring on the body these layers show up as go-faster-stripes. When the hardware gets bolted back on, this is really going to look smart.

Back in the land of fboard lights, the plastic dots have been shaped using 6mm and 8mm formers. The dots have been glued into the board and here are the results:

Funny how turning the lights on makes the wood get darker...

Lighting Up Time

Chewie & me decided a while ago that lots of little wires and lights inside a neck would no doubt cause trouble. Lights are essential, but wires need to be kept to a minimum. Space is pretty limited so we came up with the idea of using a long piece of veroboard cut to shape to connect to all the leds. The walnut fboard stiffening was removed with a dremel mini circular saw and a chisel. It didn't need to be exceptionally neat as it will be hidden from view eventually.

Blue surface mount leds were ordered a few months ago, but they didn't look that blue to me. A second lot of leds were sourced and these looked a lot nicer. These ones were even smaller - 0603 size, 1.6mm by 0.8mm! Each led has a 100 ohm series resistor, and all these led / resistor combinations were connected in parallel so that only two wires are needed to be fed into the main body.

Soldering surface mount parts can be quite tricky. The small black rectangle at the top of the board is the resistor. These are 1206 sized (3.2mm by 1.6mm). The led is barely visible, but is soldered between the resistor and the yellow wire coming up to meet it. This is part of the octave marker, the other resistor / led is at the bottom.






Strangely I found that two of the ten leds were more green than blue. They were all packaged in a strip so I was expecting a much better colour match. Fortunately the ibanez neck only needs eight, so the two dodgy ones were saved to look green on another day.



Once all the parts where fitted, the assembly was tested, run from 5V with an extra 470 ohm resistor. To reflect as much light forward as possible, the veroboard, solder & resistors were painted white. A hole was drilled at a particularly cunning angle in the neck and the fboard was placed on top to give an idea of how the finished neck will look. Not bad methinks. It still needs clear dots put in place, but it has definitely livened up the old-timer...

Back To The Ibanez

I haven't done much to the Ibanez bass since the fboard was sawn off a few months ago. The fboard itself was quite fragile, and the neck was quite warped. In fact the neck was so warped if it was thrown in the air, it would have probably come back again...

The top of the neck was planed straight again which removed a fair bit of material. The back was sanded to remove the mess left by acetone and old cracked paint. It is amazing how much wood isn't there! As the neck thins down near the headstock, the large 1/2" wide by 3/8" deep channel doesn't seem to have a great amount around it. It is only 15mm deep around the first fret. Blimey. It is not surprising that heads snap off on occasions...

Talking of snap off, the fboard did actually fall apart. The saw got a bit close at the 19th fret and was just held by a few hairy bits of rosewood and some finger lint. It didn't last long.

The back of the fboard had to be carefully sanded to remove the worst of the saw marks and to give a suitable surface for gluing. I had some walnut left over from my sandwich making a few weeks ago and managed to whittle it into a (slightly larger) similar shape. It was planed down from 6mm to around 3mm and then the large part of the fboard glued onto it.

The following day the last part of the fboard was also carefully glued into place now that the main part was unlikely to wander. Once dry, the walnut was then sanded back to the outline of the original fboard and the dot holes redrilled.

The next stage for this fboard is to receive some LEDs. These need to fit in the 3mm walnut zone and have clear acrylic dots covering them in the fboard before it can be reunited with the trussrod. 3mm should compensate for the sawing, sanding and planing that the neck has had to endure in order to sort out the original duff trussrod problem. Well, I hope so...