Seems like I’ve been putting this bit off for so long now – but I’ve been waiting until I’ve managed to work out how to make my definitive scratchplate. Of course – that’s all been messed around with my vision problems, but with a half-decent plate now in the bag – it’s about time I got re-aquainted with the “Dragoncaster” build.
I’ve been refining the template, and my technique with each attempt at a prototype plate. But I’m well aware that the final fitting may require a bit of fine-tuning and slight modification. Because the scratchplate has to fit squarely on the body of the guitar between the neck and bridge – there’s a narrow landing strip when it comes to positioning. However, the neck pickup position is also fixed, and the pickup cutout needs to be spot on. Also, the control plate needs to fit tightly up against the scratchplate, whilst also appearing to run parallel to the edge of the bridge plate. There are fine tolerances all over the place. A first test fitting shows that the neck cutout needs to be enlarged a little, before the plate will lay anywhere near flat, on the body. Since I can’t begin to check any of the other alignments properly until the plate sits flat – that’s where I need to begin.
Checking that the plate is sitting flush against the top edge of the neck – the alignment still looks equidistant around the bridge plate. It therefore looks as if I need to adjust the neck fitting around the area of the small tab protrusion, at the lower edge of the neck heel. As with all fine adjustments – it’s a matter of making small adjustments and then re-checking. It’s easy enough to pare away little shavings of polycarbonate with a sharp Stanley Knife blade held perpendicular against the edge of the plate – but it takes a good while to work through the, approximately 1mm, of extra plastic here. All the time I need to take care not to force things and end up cracking the plate – or accidentally breaking off too much of the little tab. It helps to feather each paring – so that the scraping action blends gently into the 90 degree curve, and slightly onto the edge which runs along the heel of the neck.
Of course – it occurs to me half way through the process – I should have scribed the plate to fit, before applying the holographic foil. So I need to take extra care not to tear the backing foil as I scrape the edge of the plate. As raggy bits of excess foil become visible, I cut the fine slivers off with a sharp blade – following the new curve closely as I go. Eventually, the plate drops into position. It’s tight – but there’s enough play to allow the plate to move up and down, just a little. I now need to check the plate’s position against the bridge plate, and around the lower horn, and curve of the body.
I centre the plate so that it sits equidistant – either side of the bridge plate. The fit at the neck is still good, and there are no visible gaps. However – the fit at the neck horn is obviously out a little. The line of the plate follows the lower curve of the body nicely. It continues around the lower edge of the horn, and runs OK to the tip – but then it begins to run a little too close to the top edge. Again – a little reshaping is required. Once again, a sharp blade scrapes away unwanted material along the curve. It’s much easier this time, and after a few test-fits and repeated fine-tunings – the plate sits nicely, and seems centred. The fit at the neck is good – the bridge looks central, and the line of the plate exactly follows the curve around the body.
I’m fitting the Don Mare “ZepOTone” neck pickup within the body – rather than fitting it, via adjustment screws, to the top of the scratchplate. The screw hole positions are already pre-marked within the pickup cutout – but they’re covered over by the conductive foil I’ve used. They’re easily located by rubbing down the foil, and I drill suitable openings for the inch long, stainless steel adjustment screws. There really isn’t much room in the cavity – so the pickup wires need to be fed along into the diagonal wire rout, as the pickup is eased into position. The pickup itself sits on a little pad of neoprene foam which I’ve cut and shaped. This will act as a spring. Since the neoprene foam exerts a bit of force against the screws, I’ve found it’s a good idea to plug the pickup attachment holes with glued matchsticks first – before finally positioning the pickup and driving the screws into position. This provides a really good key for the long, thin screws to bite against. The pickup is set at it’s approximate height – although there will obviously need to be a final adjustment during setup.
While I have the pickups out of the box – I take the opportunity to fit the Don Mare bridge pickup. This fits into the bridge plate using three stainless steel screws, and three short rubber tube sections. These act as resistance springs, and help hold the pickup at the correct height. With the pickup fitted to the bridge plate, the plate can be re-installed, (checking that the grounding wire is in good contact with the plate as it is reseated). The pickup wires are also routed through the conduit hole into the control rout, where they meet the wires leading from the neck pickup, and those coming from the jack socket. All of the wires are tucked out of the way, temporarily, inside the control rout.
With the neck pickup in position – it’s now important to check that the scratchplate still sits correctly, in position. The good news is, the plate sits properly and the pickup also sits roughly central, within its’ opening. It is, perhaps, just a little tight along the top edge of the pickup, and a little loose below, but I don’t think it’s enough of a problem to warrant a remodelling of the pickup opening at this late stage. The pickup screws will flex enough.
The last component to position is the control plate. This needs to fit tight up against the scratchplate, whilst still running parallel with the edge of the bridge plate. A test fit shows that the chromed plate sits in the correct alignment, but that the semi-circular cut-out on the scratchplate is just marginally too tight. Once again – a little paring away of surplus polycarbonate at the lower edge, soon allows the control plate to sit snugly in its’ correct position. I double check with a measurement gauge, and I’m about a quarter of a millimeter off, over the full length of the bridge plate. It’s not spot on by any exacting means – but again, it’s not enough of a problem to warrant a drastic remodelling. The important thing is – it looks right.
With the position of the scratchplate now absolutely defined – I can drill out the holes for the securing screws. Since the screws will be tapping through a gloss, nitro lacquer coat – I need to countersink the openings a little, to ensure the threads don’t crack the surrounding lacquer. I use a sharp brad point drill to mark the drill hole centres. With the scratchplate firmly taped in position, and using the screw openings as a positioning template – I turn the brad point anti-clockwise, by hand, to both mark the centres, and to cut the beginnings of a circumscribing countersink opening, through the lacquer coat. Each hole needs to be sunk until the surrounding countersink hole extends down through the paint layer – below the lacquer clear coat. This is repeated for all of the screw holes in the scratchplate.
The scratchplate is then removed once again, and each of the screwholes is enlarged. This time with a sharp HSS drill tip. Once again, working anti-clockwise, the drill tip is used to erode away a slight countersink opening, around the very centre of each screw hole. Finally, each hole is tapped in the centre to receive the correct screw thread. From the image above – you can see that there’s now a clear distance between the edges of the screw thread and the lacquer coat. There’s no way that the thread can pull or lift the lacquer up and off the body.
The scratchplate can now be screwed down into position, and it’s starting to look a bit like a finished guitar.
Finally – with the scratchplate firmly held in the correct position – the two screw holes for the control plate can be marked and drilled. These need to be exact – since any slight movement of the screw as it seats into it’s countersink, can drag the plate out of position. It’s vital to hold the plate firmly in place whilst the exact hole centres are marked. It’s then equally important to countersink the holes into the body using these exact screw centre positions. That way – once the plate is finally screwed down – it sits right up against the scratchplate, with no tell-tale gaps. It seems logical to drill the front hole first, so that one screw can’t pull the other out of line. (And ignore the orientation of my control plate in this shot too. I’ll be fitting the plate correctly once the electronics are onboard).
And electronics is the next job on the list…