The Learning Curve

I put on four or five coats of bright orange spray paint and allowed it to dry for a few days. I then lightly sprayed two coats of glitter paint to give the flat orange colour some added sparkle before putting on another half-a-dozen coats of clear acrylic lacquer. The can said allow two weeks before using rubbing compound! It was looking really good, but it was a long wait before I could do anything else to it.

I was starting to get quite excited about nearly completing the bodywork. All this waiting for solvents to evaporate is quite tedious, but a necessary evil. During this fortnight I took the opportunity to see how the pickup fitted. I had to enlarge the hole in the centre to allow some space for the cables, and drill three fixing holes.

As the lacquer had dried to a bobbly finish, I got the wet'n'dry 1200 grade out to get the surface smooth again. I rinsed it down and set to work with 2500 grade. Definitely promising. Another rinse and out came the rubbing compound. A good dash of elbow grease later (rinse!) and I'm onto an old bottle of T-cut which will provide the final polish. Wow! It looked really shiny, but it has got a bit wet throughout the process. I was so pleased with the result, which was multiplied by the fact that I wouldn't be messing about with sandpaper, paint & polish any more. I shook the drips off and brought it back indoors to dry out as the garage gets a bit damp this time of year (especially when I'm throwing water about).

The next morning I noticed the central heating had stopped working. I did a bit of prodding about, and eventually it became apparent that the previously very noisy pump was now really really quiet. This is not a good sign. I went to work and took a detour on the way home to get a new C/H pump. All I had to do was isolate the valves each side of the pump and swap'em over. Of course, like any good soap opera, the ending can always be predicted. The valves were seized onto the pump, so the system had to be drained and the valves replaced. The new valves were fitted and then it became evident that they were shorter than the old ones. I looked online for 22mm / 1.5" BSP valves but no-one specifies how long they are! So the next day it was an early start off to B&Q for 7am, get some 22mm yorkshire style elbows and get the blowtorch on the go. Warmth by 8:45!

After the central heating escapade, my attention returned to the bass body, so I picked it up to admire my good work and congratulate myself on a cracking job when I did indeed notice some cracks appearing. I was understandably annoyed by this. The water I used to rinse the paintwork had soaked into the wood grain where it was exposed (neck joint, jack, pickup and screw holes) and caused it to swell in places. Capilliary action works incredibly well on maple (so it would seem) and there was little choice but to let it finish drying out and have to start remedial work. Gutted!

To minimise the risks of the same thing happening twice, I'm attacking the problem on different fronts. The bare wood has been given a diluted coating of PVA to seal it and the cracks have been filled with wood glue. I ought to spray the neck pocket with a coat of paint or two. The majority of initial sanding (400 grade?) will be done dry. If I have to resort to wet sanding later, then I'll use a damp cloth to remove most of the residue. Of course, once I get to the painting, I'll still have to wait two weeks for the lacquer to harden. I'm so impatient!

Sanding Equals Dust

Sanding is quite dull. You take some paper with miniature rocks stuck to one side and rub it a few times against your piece of tree. This enhances the look of the wood inversely proportional to the ache in your arms. In the meantime everything gets a liberal coating of dust.

 

Some of the larger gaps had to be built up with polyester car-body filler and smaller holes with knifing putty. Both of these products are quite uncontrollable (in my hands), but I threw in a bit more sanding to compensate.

 

 

If wood dust isn't sufficient, sanding through layers of paint and filler gives several different colours of dust. I tried light brown, white and two or three different shades of grey. Not fifty though - it's the wrong sort of curves.

 

 

Perhaps a camouflage paint job would have been an idea? This shows the high-spots and low spots left by the straight grinder. Then I did some sanding.

 

 

A lot of the time it is difficult to see any improvement. Whilst waiting for signs of progress it is worth doing some sanding to pass the time...

 

After a bit more sanding, most blemishes are blended in fairly well. This process could carry on almost indefinitely, but I'm not a stickler for absolute perfection. A few more coats of Filler / Primer and I reckon it's nearly ready for the top coat to be applied.

 

  

 Strangely, the filler primer is a light brown / orange sort of colour. Looks promising...

 

 

I think six bolts should be enough to keep the neck on.

More bodywork

Creating the neck pocket took a while. The neck was carefully measured and the slot cut deliberately undersize with a saw. This was then whittled away with a chisel until the slot was *just* large enough to accept the neck heel. Six holes were drilled in the back so that the neck could be fixed securely. After that, it was time to assemble the basic bits to see if it would snap as soon as some string tension was wound in.

Fortunately, apart from an awful 20mm action height, it survived. I had aligned the bridge and neck etc so that the strings were centralised. As can be seen from the photo, this wasn't terribly successful. The string tension was sufficient to compress the 'C' shaped body and start to close it up a little. The E string was nearly off the f-board, whilst the G had more than enough space. The body bending is something I will just have to live with, so I allowed it to settle for a week before moving the bridge mounting holes down a few millimetres. I also took the time to remove some body wood from under the bridge to get the action down to about 3mm. Once refitted, the whole experience was more civilised...

This is the point where it could be played (acoustically) if only it fitted on my lap. It really needs a strap, but that will be one of the finishing touches. The other point is that the body alone weighs 3.7kg without any hardware! It feels much heavier than expected. The stainless steel reinforcement won't be seen once finished so I'll can try to convince people that it's filled with concrete...

Curves

Now that the whole will-it-snap possibility was sorted out, it was time to get rid of the blocky look. The maple body needed to be shaped which required the removal of quite a lot of wood. An orbital sander would not cut the mustard here. Some new toys had to be found - enter a DWT Swiss GS06-27LV Straight Grinder and a couple of Foredom Typhoon carbide burrs.

The body and neck were separated once more and the grinder was used to give the body a roundish cross section. Goggles, ear plugs & dust masks were the order of the day. The bridge and neck pocket areas have to remain flat and blocky, so the trick is to try and blend them in.

 

The rough shaped body is a great improvement over the slab look, but the process creates a huge amount of really fine sawdust. I made a dust castle in its own lunar landscape...

 



 

After the grinder had done the bulk of the work, there are several gouges and grooves which usually result from me using power tools. This time they were in the wood and not me, which I take as a good sign. Hand sanding with 60 grit paper is the first stage. It needs to look right at the end of this! I think it's going to be a long job, and I will also need to use some filler in places too. I foresee a lot more sanding ahead. Bored now...

 

 

Nuts

Due to the springiness of the stainless steel and the maple, the middle section needs a bit of clamping to keep it in the right place. Whilst the body parts are being glued together (not now Igor...) it seemed like a good time to have a go at the nut that should be on the neck.

 The original nut was a broken creamy-coloured plastic item that didn't inspire much confidence. The garage was invaded to see what was about and eventually I chanced upon an old PentiumII heatsink assembly. This was an old one - before they decided that everything gets a fan. The heatsink assembly consisted of a flat aluminium transfer plate and a separate finned thing. The black anodised transfer plate was 3mm thick and appeared to be a harder grade of aluminium than the regular stuff that often crops up. An original fixing hole would provide acces to the truss rod - great!

The aluminium was sawn and filed into shape whilst being protected from the vice jaws by small pieces of card. I marked out the centres of the slots and made them 3/8" apart. Once the corners were rounded off slightly, the nut was able to be used as a guide for the chiselling that was required on the wooden nut-holder!

Chiselling the neck was done as carefully as possible to avoid messing up the impressive paint job. I don't like the idea of just gluing a nut on without some decent foundations. When a note is fretted it probably makes virtually no difference, but for an open string it must have an effect.

Time to inspect the gluing of the middle section before the top layer is put on. It is looking pretty rough, but the revised pickup shape looks much more circular.

Here is the nut in place on the neck. It needs a bit of a tidy up round the edges, but nothing major. With the benefit of hindsight, I can see that the string grooves don't look equally spaced, and that maybe I should have used a fixed distance between the strings instead of their centres. In other words the string separation should be further for the fatter E string. Smeg! I might have to whittle the grooves a bit somewhen.

The neck to body joint will be the next thing to tackle...

Curly Wurly

The maple was routed into semi circular shapes (orange segments?) and then routed again to provide a smaller inner radius. The finished parts were C-shaped. The body is going to consist of three of these glued together, but the inner one is going to be strengthened with stainless steel first. To allow space for the steel, the inner C-shape is routed another couple of times until it is in three parts itself. The steel will live in these newly routed channels to form a steel-maple-steel sandwich. This composite approach offers the best strength that I can reasonably knock-up in my garage.



Here my two faithful accomplices demonstrate the wonders of the bending machine. Thanks to Nicky & John showing "after" and "before" and to Chris (not pictured!) who seems to have an endless supply of useful gadgets yet again.

The 20 x 3mm steel bar is fed back & forth through the rollers whilst they are progressively tightened. This gradually bends the steel until it gets to the right radius. What a great gadget!

Here is the sandwich style inner layer layed out to check that it fits. When finished, this will be hidden inside and not seen. The steel bars (two in each channel) will be bolted through to keep the whole assembly rigid. Not quite as good as a box section, but along those lines...



Boring

6mm holes were painfully drilled through the stainless steel. I'm used to drilling through wood, plastic and aluminium and even mild steel on occasions, but drilling stainless is a whole different ball game. The stuff is nearly as hard as the drill bits themselves. I had 4 lengths of 3mm thick stainless - each one has 9 holes - that's 36 in total. I must have got through at least 12 drill bits. Some snapped, but most just lost the will to live and the cutting edges 'dulled'. Officially dull and boring?

 Here's the finished middle section. The M5 button heads can be seen clamping the whole thing together. It seems pleasantly stiff. Maybe that sentence needs work... It weighs a bit, but I like to think that this will transform into a well balanced guitar. I hate it when the neck continually dives for the floor. Most of the excess stainless has been trimmed away, but a couple of short overhangs were left to key into other parts of maple that will be glued on later.

The first layer has been glued together to illustrate the rough shape of the body. The steel reinforced layer will be next. The centre 'blob' doesn't seem quite large enough so that may have to be adapted. Fortunately this one is going to be painted so even if it is all plastic filler & newspaper it won't matter...

Orange!

The neck is looking good so far - time to get some colour on the headstock and refinish the back. The back was easy once the sanding was completed. A layer of Danish oil, let it dry for a day and then apply a layer of wax. Once this is fully rubbed in it is impressively smooth.

The headstock was degreased and treated to 2 coats of grey primer from a spray can. Once dry (a few hours) this was gently rubbed down with the 2500 grit wet&dry before a coat of Ford Focus Electric Orange was applied. I had used this for the front panel of the valve amplifier and it is a great colour.

My wife Nicky had to break the sad news to me that my orange paint was in fact now gold. Perhaps it doesn't last for 18months in a cold wet garage. Maybe all the juicy orangey bits had gone mouldy? But the end result was not orange and therefore was not going to be staying. Another wander off to Halfords and I came back with a can of fluorescent orange paint. Even being *slightly* colourblind I knew I was on to a winner as it had orange written in big letters down the side. I also discovered spray glitter. I now knew what had to be done!

The previous gold was sanded back a little and 3 coats of the solid bright orange paint were added. Again, this was allowed to dry for a few hours before a light sand and a couple of glitter coats added before another 5 coats of clear lacquer were applied.

This was allowed to dry overnight before a further light sanding (to remove the bobbly finish from spray can painting) and then the T-cut was used to buff to a shine. Photos just don't do it justice. The paint is toooo bright for the ageing camera ;-)

Body Work

Now the neck is done apart from fitting a nut at some point, my attention turned to the body. I spent some time looking into hardwoods that combine a decent amount of strength and machinability and it boiled down to good ol' maple. I found a decent plank 2m x 22mm x 220mm at the local timber merchant for less than £20.

The tricky part of the body is the bottom section. This is mostly because there is no top section (see earlier sketch) and this has to take the full string tension whilst looking like a micrometer. I am going to use a stainless steel bolted sandwich style re-inforcing technique which I have mulled over with a few other engineers (thanks Robin / Chris)

To get the strengthening to fit together properly I'm going for a constant radius for the lower section. I borrowed a router (thanks again Chris!) and swapped the parallel fence for a pice of bent rod and this allowed me to cut out several semi-circles. There will be three glued together (with the steel in the middle one) eventually before it will be shaped to a round cross-section.

I need to draw out the shapes for the top horn and the pickup holding section too before I start getting the glue out in earnest. I can see this is not going to be a light guitar, but if it is rigid enough such that tuning one string doesn't mess up the other three then I'm happy!

Orange cocktail sticks!

The perspex fboard slots are looking fine, and the next job is to get a smooth radius across it. Fortunately I already had a small piece of ash left over from MoonBassAlpha that I used to check the neck radius (around 12" or so), so I was already ahead of the game. No substitute here for sandpaper and elbow grease. Give me a power tool and I could really mess things up badly, so its a case of getting the 60 grit paper out and 'aving a rub. Don't bother with abrasive paper from the cheap shops as the sand disappears at the first sign of action! Insert your own political comment here ;-)

It is the usual case of getting the shape roughly right with the 60, and then progressing through the grades (80, 120, 180, 240, 400, 600, 800, 1200, 2500) and then getting the metal polish/T-cut out to finish off. I couldn't believe that Halfords did 2500 grade paper - it's smoother than a smiling salesman covered in baby-oil. I expect.

Due to the neck widening near the heel, the constant radius causes more material to be lost at the edges there than at the head end. Because of this, the neck had to be put back on the slot cutting jig a second time so that from around the 8th slot onwards the grooves could be deepened. I suppose I should have realised this whilst cutting the slots originally, but I must have been getting hungry at the time ;-)

The frets were then pressed into the slots. Where I had recut the slots, they seemed a little wider as though the circular saw alignment was a bit adrift. A tube of superglue came to the rescue here, but on the whole, the acrylic was a good material to press frets into. None of them have fallen out yet which is the main thing.

The fboard was protected with masking tape and the frets were lightly levelled and dressed before being polished. The edges were chamfered a bit so I don't cut my pinkies.

At this stage I also sanded off the old black paint off the headstock, and the scratched lacquer off the back of the neck / head. This came up very nicely and it is starting to look like a new piece of neckery instead of a lump of old flea-bay. The visible ends of the frets were also treated to some white paint so that they do not stand out too much. I think it is safe to say this is cheating.

I then considered my options for neck dot inlays. I did not want to spoil the i-bass look from the front, so I just needed side markers. The perspex is a bit too thin at the heel end, so the markers are best placed in the carbon fibre section. I wanted to get hold of some orange plastic rod which could be cut into short lengths and would look great. Nobody I could find makes 2mm orange rod.

Whilst observing somebody in the pub with a complicated drink (ie not a pint), inspiration hit me in the form of plastic cocktail sticks. Not literally though. I scoured the local shops and online and realised that everyone is now using wooden cocktail sticks. What is up with the world? Why use environmentally friendly wood for culinary articles when cheap nasty plastic could have done the job in a much more tacky way? Plastic cocktail sticks must have gone the same way as the Kenwood sodastream, space hoppers and nylon slacks. Smeg!

The second choice was 2mm dia aluminium wire. I drilled 2mm holes in the carbon fibre (which was tougher than I thought) and then bashed the aluminium wire in, followed by some filing down and light sanding. Shiny. Quite nice and up-market looking. I still would have preferred cheap and trashy, but that's me...

F-board slot cutting

The fixture used on the Moon Bass was built around a flimsy mini-drill that had a flexible shaft and a small circular saw at the end. This possessed much better timing than I normally do when playing as the flexible shaft sheared as I finished cutting the last slot. Phew!

This time I used a proper Dremel, and got hold of their mini circular saw attachment which is a bit more sturdy. I had to get some 18mm MDF sliced up at the local B&Q place as they cut so much straighter than me, and then pieced all the bits together.

Of course, the granite bed and GPS controlled servo system may have worked, but up against steel 19" rack hardware, kitchen drawer slides and a small piece of 40mm thick laminated chipboard, that kind of old-hat technology was never going to get very far ;-)

I had to whittle a matching strange shape so that the Dremel saw could be clamped as there is no specific way of fixing it.

I had previously used a small 1mm drill in a milling machine at work to mark where the slots should be accurately-ish, and all this jig has to do is allow a perpendicular cut to be made. Sounds easy.

The perspex now sports freshly cut slots, and in the right places. It doesn't get better than this. Well, not round here anyway. The fboard was carefully prised away from the extremely sticky double sided tape, and after a quick degunk with acetone, the fboard was glued onto the neck with more epoxy resin.

The bond was held in place by a couple of clamps, and a really nice transformer that Robin found in his garage. This looks to be approx 300VA and measures 125 x 125 x 110mm. It has a split primary and binary weighted secondaries. It sounds *perfect* to replace the feeble 50VA toroidal unit in my 50W valve amplifier as an output tranny. I'm using it here as a bloody great weight, but I can see its potential elsewhere...

Now the glue has dried, the chips are down, the word is out, and the time is right. The edges have been trimmed back and it is starting to look like perspex wasn't such a bad move. I think the final proof of that one will be when the frets get bludgeoned in ;-o

Oh, I rigged up the transformer (bypassing the toroid) and it sounds glorious! I can see the next dilemma coming up on the horizon as there is no way this chunk of iron is ever going to fit in the valve amp's 3U case. I will just have to make a bigger one...