A week in which a guitar is delivered

My notes from this last week are short but decidedly sweet: The Clydesdale guitar finally shipped to its owner, Stewart Matheson of the band Layaway.

DSCF5359 3.jpg

You can see Stewart having a little play on the guitar on his instagram account here.

The week before I had done the first pass of the setup on the guitar, getting it to play well with strings that I was familiar with, and then this week I did a second pass at it with the heavier gauge strings Stewart wanted. Moving up from 10s to beefy 11s required the nut to be filed a bit more, and in the end I’m quite pleased with how the setup went, mostly thanks to the new nut files I’ve got. At some point I’ll have to go revisit some of the older guitars and check how they’re setup. 


The final setup done, I had a wee session on the guitar myself to hear it rock out through my amp and pedals, and then I headed up to Glasgow with it to hand it over to Stewart in person. Driving the better part of 400 miles is a slightly excessive way to deliver a guitar, but in part I wanted to hand this one over personally given how delayed it had been, and I do have friends and family in the Glasgow area, so it was a good excuse to visit them too.

Stewart has a pretty sweet rig at home for testing with: he plugged The Clydesdale into his Victory V30 amp plugged into a mix of Strymon and Walrus Audio pedals, and the combination of all these things sounded sublime in his hands. You can head some in the video Ilnked above, but in the room it sounded just perfect - I just closed my eyes for a bit and listened to him explore what The Clydesdale can do. It’s this that makes all the effort worthwhile, and I’m hoping that I’ll get to go see Layaway gig later this year and see The Clydesdale in real action.

A huge thanks to Stewart from me: he’s been very forgiving of the delays that we’ve been through in getting this guitar finished, understanding why things were slow, and having belief that it’ll make good in the end. For anyone else struggling with a project I can only encourage you to be as communicative about things as you can and keep your client in the loop. Things don’t always go right, so just be upfront and honest with these things.

I spent half a day trying to make a video for the Prototype Offset guitar I want to sell, similar to the videos I’ve made before, but I really struggled this time. I managed to get something, but it was a lot more mentally like getting blood from a stone than I’d expected from previous experience. Still, it’s forced me to kick the tyres on Adobe Premier Pro for pulling together the video, as it required a lot more editing to get the video than I’d thought.

I managed to see another gig last week, with amusing and frinetic bluegrass sounds of Whiskey Shivers coming to Cambridge. We saw them last year at Wilderness festival, and it was nice to see them in a more intimate venue. 


They were supported by Dana Immanuel & The Stolen Band, who were equally as amazing as the main act, and their album “Come With Me” has been on repeat most of this last week. 


The DI&TSB album is great, but if you get to see them live then I can really recommend it: much more energy coming across from the band (not that the album lacks energy, just they turn it up to 11 on stage). As a guitarist I was particular impressed with sounds that their guitarist Feadora Morris made live, going from gentle fingerpicking one minute wailing grungy messed up sounds the next - the sort of things I wish I could play, executed much better than I ever could. I couldn’t make out the make of guitar she was using, but it looked a lot of fun: an ES style guitar with a P90 in the neck, a humbucker in the bridge, and a bigsby wiggle stick.

As a final nice touch to the gig, Whiskey Shiver’s encore had both bands come together in the middle of the audience to play a couple of acoustic numbers. Such a great thing to do when you have a smaller audience, and it’s not often you get to high five the band at the end of the gig :)

A productive week in the shop

Last week The Clydesdale offset build finally came together, which has made me very relieved/happy.

At the end of last week I’d put it all together and strung it up to discover that the neck was sitting a bit too high and I needed to route out a bit of material from the neck pocket to compensate. It turned out that wasn’t the only thing that needed tweaking: when I sat down to prep for routing out the neck pocket a little to lower the neck, I noticed that the low E string was particularly buzzy, and upon closer inspection I discovered that one of the frets had shifted over time to sit proud at the low one end, which resulted in buzzing for any note played behind it. Wood shifts over time, so although frustrating, this is something that just happens occasionally and has to be accepted and dealt with. Thus before I could adjust the neck I first had to fix the errant fret, as nothing I did on the neck position would fix that problem, and I’d not be able to tell how well the neck was positioned with the fret causing issues.

I tried my best to reseat it without removing it, but in the end I couldn’t get it set correctly, and even if I did I was worried it might unset again, thus in the end I bit the bullet and re-did the fret from scratch. I taped up the neck to protect the fretboard, carefully pulled out the rest of the fret, and then put in place a new one. This replacement fret sat in much better and held fast. But now I have one fret that is higher than all the others, so it was time to file it down level and reshape it to match.


Filing down one fret without damaging the others is slow work, but after an hour or two of filing, measuring, filing, measuring etc. I got the replacement fret down to the right level and polished it so it looks just like the others and you’d not know it was treated special. With all the frets back in place, next it was time to lower the neck pocket on the body.

Taking material away is obviously easier than adding material back, but because the body on The Clydesdale has been stained and oiled to finish it I needed to take care not to scratch the now beautifully surface. The tool to remove the material for a task like this is a hand router with a following bit - that’s a bit with a bearing the same radius as the cutter, so I can just move the hand router within the pocket to remove material from the bottom, and the bearing will stop me eating into the side walls of the new pocket. But a hand router has a large flat base that it uses to keep itself stable that slides around the top surface of the thing you’re working on, and that’s where scratches might occur. To counter this I used a combination of cleaning cloths and a small jig made from ply to sit atop the body and protect it, and the result looks a little like something from an operating theatre:


I actually still had the original body for the The Clydesdale that the CNC Router ruined sitting around, and above that’s what I’m using as a quick practice run. It had the same neck pocket depth so needed the same treatment anyway. After I was happy I’d got my technique down on the test body, I repeated the process on The Clydesdale itself. Here you can see the results:


Before I got to the workshop I checked the neck heights on my other guitars to work out what my target height would be. My tele’s have  the fretboard about 5 to 6mm proud of the pick guard, and The Clydesdale was at 7.4mm, so all I needed to remove was 1.5mm to get it in line, which I can do easily in a single pass. I was worried that I might need to touch up the finish on the edge of the neck pocket where I’d removed material, but as you can see there’s a beautiful clean line; I only had to remove a sliver of material here, and my router bit was nice and sharp, so it gave a nice clean cut. 

Once done I then strung up the guitar once more, and everything was much happier. A day of stressful work, but all worth it.

The following day I sat and started the setup. Jamie of Swannell Guitars, who stopped by the workshop briefly this week, gave me the sage advice that I should spend a lot longer on setup than you think is required, as it’s the setup that really defines how a guitar feels to the player. So I put on it a set of strings I’m familiar with (so I’d understand how the guitar felt, rather than using the strings the customer wanted straight away where i’d be less able to tell) and spent the afternoon filing the nut, tweaking the bridge height, getting the intonation set. By the end of the afternoon the instrument was really starting to make me forget all the woes of the last year, as it became something that was lovely to play.


It’s not quite done: obviously I now have to put on the strings the customer wants, which are of a heavier gauge and thus will require the setup to be tweaked a little more. But once that’s done, it’ll be up to Glasgow with this guitar to hand it over! 

I set up my pedalboard prototype now that I have the replacement PSU, and it’s looking great, even in it’s somewhat sketchy unfinished-metal-and-MDF-end-caps sort of way:


The positioning of the cable routing slots in the top surface fits perfect (as it should do given I measured it all out), and at the same time I upgrading my cables to use custom length patch leads, there’s so much more room on the board than before. On my old board I’d have been able to get just one more small profile pedal on, but here there’s quite a bit of space if I were to squish all the pedals together.

The rest of the routing works well too: you have power, going in the top, and guitar in and out for the entire board on the sides, so it’s easy to pick up and move around. Not visible here are the slots in the sides that are there to make it easier to pick up whilst keeping the top side free of handles that would block pedal placement. All in all it’s what I hoped from the design.

I’ll live with this for a week to check it stands up to abuse: for example, the wah is deliberately in the middle of the board currently where there’s the least support to check it doesn’t give. Once I’m happy I’ll go back to the metalwork manufacturers and review the finishing issues I had with this one and start deciding whether I do another prototype or perhaps even move onto a small small production run. The idea is that for the production run the metal will be powder coated black, and the end caps will be made from some pretty figured wood to make it something that you’d be happy to live with in the studio or your living room. That said, I actually like the bare metal look - what do you think?

I also found a little time to get the electronics on my pedal switcher to the point where I have all the components in place and validated that they work end-to-end.


The last stage was to add the relays that would control the audio signal path, which you can see here as the little white boxes on the veroboard, one on the bottom right and another in the middle. Here they’re just wired up to red and green LEDs, but that’s enough to let me see them switch as expected. The kind of relay I’m using is a latched relay which should save on power draw, but also requires more thought to wire up than just hooking it up to GPIOs on an embedded controller. I’m still quite slow at relearning electronics, but I seem to have managed to get these working with a little educated guess work :)

I also have just off the top in that picture a power supply board that let’s me run everything off a standard 9V centre negative power supply as you would an effect pedal. This means that my switcher can use whatever power setup you have for your pedals already, rather than needing its own.

Next steps for this are to figure out how I’ll assemble it into a boxed thing with connectors so that I can order those bits and build a functional prototype.

A week in the shop

At the end of last week I had successfully, after a bunch of failed attempts, cut out a pristine pick guard for The Clydesdale offset guitar, so I started this week by bringing together all the bits of the guitar and working on the electronics. First was just to get all the final bits together onto the guitar. Here it is from the front:


and from the back:


It’s looking lovely. I did a quick rough shaping of the nut, but that’s one of the last bits to do at final setup time, once the electronics are done and we’re just dialling in the final playability.

The electronics took me longer than it should of because I have a tendency to leave as much wire on the pickups etc. as I can, just in case someone wants to re-purpose the pickups later or other such events. However, there really isn’t much room to manoeuvre in this guitar, so I ended up effectively wriring everything up twice: first with lots of spare wire, and then having realised I didn’t have enough space in the body cavities for all that wire I then had to unsoldered everything, cut things to a better size, and put it back together again (and thankfully it all fit nicely this time). Partly the limited space is down to the mustang not having much room under the metal control plate combined with using push/pull pots to let the player switch the pickups between humbucker and single coil modes - fender really didn’t have this in mind for this kind of guitar. The other reason for the lack of room was my own doing: in an attempt not to remove too much wood from around the pickups (to leave the body being solid rather than hollowed out) I’d left not a huge amount of room when I designed the space behind the pick guard: in retrospect I should have left more room. Still, we got there in the end.


Electronics done I could finally string up the guitar and see how much setup was needed. This is where I discovered that the neck is sitting too high for the fixed bridge on this guitar, and the strings were buzzing on the frets even with the saddles extended as high as they’d go.

This hadn’t been an issue on the prototype offset, which used the dynamic vibrato bridge system, and that bridge naturally sits quite a bit higher than the hardtail bridge the customer wanted on this build. I did have a look at Fender’s Mustang guitars with a hardtail bridge, and they do tend to have them with the saddles set really high. In the photo below you can see quite a lot of screw under the saddles on the bridge, more so than I’d expect on say a Strat.


However, on The Clydesdale it’s just a bit too much: I think I need to take a millimetre or so out of the neck pocket to get things sitting comfortably. So this week I need to take the neck off and with the hand router remove some wood from the neck pocket using the hand router and a short follow bit. I’ll need to make a small jig to let me use the hand router over the finished body without scratching the surface, but I’ve actually done this before on The Chuncaster t-style I made early on, which had a similar problem.

The frustrating bit about it is I find out these sort of things at this late stage in the build: ideally I’d string the guitar up early on before doing any finishing. However, with Fender style guitars this is something I’m generally reluctant to do, for two reasons. Firstly, when you assemble the guitar and put it under tension by stringing it up you’ll find the metal parts like the tuning pegs and the neck plate will mark the wood as they press into it. Doing this after you’ve oiled the wood makes such marks less pronounced as the oil toughens up the wood’s outer surface. The second reason I try to avoid it is for string through guitars like this one I’d need to put in the ferrules on the back which then I can’t typically not remove, but would like to not have there when I do the finishing. Hence why I only tend to find out now that I need to adjust heights etc. after it’s finished and I then need to be very careful about such adjustments.

Mostly all this is down to a lack of experience: if I made a lot of guitars I’d be better at predicting things like this before we get this far into the process. But it is also useful learning for my own guitar designs. I think with a bit of tweaking I can design the guitar in such a way that it won’t notably mark when assembled and put under tension before finishing (e.g., using recessed screw ferrules to hold the neck rather than a Fender style neck plate).

Anyway, I have a fun week ahead of me getting the guitar adjusted so it’s a musical instrument rather than a pretty bit of art.

The rest of the week was taken up with some sudden contract work, so I didn’t do much else in the shop. I did manage to pick up some bits for the other projects I’ve got going. I was in London for a gig (see below), so I swung by GuitarGuitar in Camden and picked up a new pedal board PSU (another Walrus Audio Aetos in the end, given I know it and have been happy with it), which means at some point this coming week I can finally assemble my pedalboard prototype and start (literally) stress testing it by mounting all my pedals on it and stomping on it bunch.

I also managed to raid the spares trove in Makespace and find the correct capacitors for the fuzz pedal I built last week.


Putting these caps in place solved the sound drop issue I as experiencing with it, and now I have that classic fuzz tone. At some point I can now take this from breadboard to some veroboard (or if I find time, a custom PCB via Eagle) and mount it on my pedalboard and have it in regular rotation.

I did get to visit another workshop briefly: I was up in Liverpool at the weekend, so I finally made good on a promise I’d made in autumn last year (where does time go?) to run the Fusion 360 tutorial course I run regularly at Makespace for the DoES Liverpool community. The turnout was less than we’d hoped, I suspect due to the inclement weather, but we had enough people to keep me busy for the full duration, and feedback seemed positive.

It was nice to meet a different set of makers; DoES has different vibe to Makespace, and I met people working on things no one is working on at Makespace.  For example, I met one chap who has been using 3D printing to make moulds for casting jewellery, and was interested in Fusion 360 so he could start using their CNC Router to make moulds by milling out material - very interesting stuff.

From a personal perspective, it was also nice to chat to Adrian McEwen, one of the founders of DoES and someone I’ve had the fortune to know for a while. Long before I set out on this, Adrian’s been forging his own path in trying to work on interesting and meaningful projects between bits of contracting and is very familiar with the trials of making physical things, so it was nice to have someone to compare notes with given all the issues I’ve had over the last year. Adrian has also been doing weeknotes, so if you’re interested in seeing what he’s been up to, you should check his notes out.

I also managed to go see one of my favourite bands, The Dandy Warhols, who were playing in London. Hard to believe they’ve been going 25 years now (again, where does time go?). They did a great set, and I love how The Dandy’s do their shows: there’s no fake encore, just one bountiful set filled with a mix of things from their most recent album and spanning a good chunk of their back catalogue. Also, and I’ve not seen any other headline band do this, they present themselves as a group of equals: all four members are in a line at the front of the stage, including their drummer Fathead; it’s a small thing, but I think makes a big statement about them being a group of equals, and not just a singer and some musicians. 


Of the support bands, I really loved the 60s psychedelic surf sounds by Juniore. You should check there stuff out on their bandcamp page if you’re at all into that sort of thing.

A week in the shop

Following on from last week, I did more testing of the DM500 CNC Router controller to test its suitability for use in Makespace, and on the test rig we have it’s worked pretty well. It’s not without it’s own idiosyncrasies, but no worse than what we have (indeed probably fewer). Next step on that will be to get it tested on the actual CNC Router itself, to check that it works in situ. But given that’s effectively a day to do, it’s great being able to know the basic functionality works as should on our test harness.

IMG_2603 2.jpeg

In terms of pros for this unit (beyond just working, which is not a bar all controllers appear to reach): the UI, whilst not amazing, is better than the current controller; it takes feeds speeds from the g-code itself (our current one can’t, so you have to set it manually each time), but you can also override it to be both slower and faster on the pendant (up to the configured safe maximum for the machine); and unlike the Grbl controllers we tried before it handles things like continuous jog properly and safely. On the down side, you can’t copy g-code onto the pendant before running it and it does incremental processing of the g-code itself. This has two consequences: it means you need to be careful that you don’t knock the USB stick that protrudes from the pendant whilst running your job, and the device doesn’t tell you if your g-code is going to exceed bounds until you get to that bit of the file. Not ideal, but then it actually otherwise works consistently and safely, which is surprisingly infrequent in this space we’ve found.

Given the downsides we still want to try the Masso controller unit we have also, but it’s great to have an option to swap out the current known bad controller.

I took a third go at making the pick guard for The Clydesdale guitar on the CNC router with the current controller: the first time it failed due to the CNC router misinterpreting some valid g-code, which I changed to workaround and then the second time it failed due to my double sided sticky tape failing to hold the material in place. This third time I ran the same known working g-code files on the CNC router, but made sure to screw down the centre of the pickups so they wouldn’t come free despite the double sided tape.


As you can see, third time’s a charm: the piece came out perfect thanks to the belt and braces method of securing the material (I’m still using double sided tape to ensure the PVC remains uniformly flat to the router bed). This means this week I can get started on the electronics for The Clydesdale - that’s all the manufacturing of bits complete!

The prototype offset has been sat to one side awaiting proper setup, which I’ve now completed. I’d been blocked on this waiting for my new set of nut files to be delivered, as I decided life was too short to keep using the cost saving trick of using nozzle cleaning files to cut the nuts. Proper nut files feel eye-wateringly expensive when compared with other tools you might get, particularly how briefly you use them (over a £100 for a full set), but I do say that they make the job so much easier: they’re both quicker to cut and more precise. 


Thus in half an hour I had everything setup just as I wanted. This also involved setting the levels and intonation on the bridge. The Mastery bridge units are lovely, and much more secure than the standard bridge for this type of guitar, but they are a little more fiddly to set up.


Still, the guitar is now setup, and I just have to work out what it’ll cost to post so I can get it listed on reverb.

My plan had been to test out the new pedal board prototype by moving my entire pedal setup to the prototype for a bit, but I hit an embarrassing snag there. When I assembled my current pedalboard two years ago I used 3M Dual Lock, a sort of industrial strength advanced velcro, to stick the supply under my board. It turns out that dual lock is four times as strong as velcro, and as a result you should use less of it. Unfortunately I didn’t know this at the time, so I used lots of the stuff to ensure it never fell off. Unfortunately this means the bond is now so strong I can’t remove the power supply from my current board! Doh!

There’s things I could do to try remove them, but it’d leave either the pedal board and/or power supply a bit worse for wear, so I need to chalk this one up to experience, and when I sell my old pedal board it’ll be coming with a nice power supply already attached :)

I need to order a replacement, so if you have any recommendations for pedalboard power supplies, let me know. I’ve been happily using the Walrus Audio Aetos this last two years, but there’s been a couple of times I’ve hit limits of it’s current delivery for things like the OWL programmable pedal I have, so am shopping around for a slightly beefier replacement.

I spent a little time on my pedal switcher logic, and I finally got the MCP23017 IO Expanders working properly. Turns out that although those chips will work at the 3.3Vs from the regulator on the ESP32 micro-controller board I have, it can’t provide enough current. I moved everything to the USB 5V supply, and all is fine. Next step there is to try connecting the relays I have to the IO Expander. Once I have those working I’ll have all the major bits in place and can try a working prototype.

As a fun Saturday afternoon project, I finally made myself a fuzz pedal. I was going through my electronic bits box whilst putting together my pedal switcher circuit when I noticed I had just about the right parts to make the very simple circuit that is the original Fuzz Face design (albeit with silicon transistors rather than germanium). I didn’t have everything right, notably I was missing the right values for the input and output filter caps, but I found things close enough, and half an hour later I was playing through my own fuzz build.


The sound is not perfect - I seem to have some power fade at points, though that could be due to my close-but-not-quite-right filter caps cutting out the wrong things - but it’s definitely recognisable as that early Satisfaction style fuzz sound. I did a little dive through the Makespace trove and now have some more bits to try and bring it closer to the original circuit next time I get a moment.

In the picture above you can see four transistors (the little silver cylinders on legs), but the circuit only uses two, so what are the other two doing?

They’re there for experimentation! I have two transistors of one particular type, and two of another, and I tried swapping them in and out for each other to see how it changed the sound. Whilst all combinations gave a fuzz type sound, I found I preferred the two that gave me a less harsh sound (using BC107s for both rather than any other combination of those and the BC108s I also had).

I actually bought a big-muff style fuzz pedal kit a while ago on the idea I’d make it, but in the end I never felt motivated to do so, as just copying an existing circuit for no other reason than to use it without change felt a bit pointless. But instead of using a PCB with a fixed configuration and making it on a breadboard like this lets me start to experiment and learn what impact each component has on the sound: I have a broad idea of what the circuit is meant to be doing, but that’s very different from being able to hear the impact of tweaking bits through your amplifier. I look forward to swapping out the filter caps in a similar fashion next time I get to play with it: when I found the extra caps I got not just the ones that are specified in the original circuit but others around the range to let me pick what I think sounds best.

And this is why there’s 1001 different pedals on the market: each one is subtly different and you have to find the right one that inspires you when used with your guitar and amplifier.

A week in the shop

There was no direct guitar progress this week, with the CNC Router still out of bounds for guitar work. We did fix the USB port failure on the current adapter so it is back in operation, but it’s on the old control electronics so I refuse to put material on it at the moment that I can’t afford to replace, and after two failed attempts to cut a pick guard on that, I’m not going to throw good money after bad.

As a result I concentrated on mostly contract work this last week to let me get ahead of that so that when the CNC router does get it’s new brain I’m ready to take advantage of it.

So, progress on that new brain. Two replacement CNC Controllers have now arrived: the DM500, a new pendant style controller, and the Masso, a more advanced unit that has lots of bells and whistles, but still has the advantage of not being a PC. Adrian, one of the Makespace directors (with minimal help from me in the form of switch pressing occasionally) wired up the first of the new controllers to our test jig (shown below with the old Grbl controller we tested initially).


Whilst I like the idea of a controller with lots of bells and whistles, in the context of Makespace that’s not necessarily optimal. Whilst there’s a small set of users like myself who are pushing to the more advanced end of what can be done, there’s many more users for whom this is their first bit of industrial control kit, and as such whatever solution we get for Makespace has to be robust and easy to comprehend. becoming a trainer on the CNC Router has been quite an eye-opener in terms of what the Makespace requirements are - it has to just work more than it needs to let you control things to the nth degree (no matter my personal opinions on it). At the same time though, we do have some minimum feature requirements, such as the ability to do 3D surfaces, not just 2.5D as per some solution (e.g., the Instructables X-Carve). Thus we’re starting testing with the simpler of the two controllers, the DM500, which I hope to start software testing on today.

In early December I wrote a bit about my side project to make myself a new pedal board. This was partly to fix something that bugged me about my current pedal board, and partly to move me out of my comfort zone in terms of making things and make learn a new skill. The design centred around a folded bit of metal onto which the pedals would attach, along with some nice wood end-caps designed to make it look nice for a home or studio setting. 

Screenshot 2019-01-18 at 15.09.23.png

Having designed the metal work, and consulted with a couple of friends who had done this sort of thing before (many thanks to Mark, Rob, and Adrian!) I commissioned a local firm to build me a one off prototype, and the metal work finally came back:


When this turned up, I was very excited to see how close what I got was to my design: it’s one thing to design an object, it’s another thing for it to be actually manufacturable. I might have designed the radiuses too tight to be folded, or relied on tolerances that were not feasible etc.

Initial impressions were that it looked very much like the design I sent them, but the question is whether it’d mate with the other parts needed to make the entire thing. The main interaction points are the wooden end-caps, and in the rear is a power socket that just passes through to an internal kettle connector, so you can mount your pedal power block under the board but still have an accessible on/off switch on the outside. There are also rubber feed I ordered and the undersides were designed to fit those.


As you can see in the above picture, the power socket and the feet mount perfectly, and the board sits nice and level with the feat on. Very pleased with this. I then cut some mock end caps out of MDF just to see how those would work (demonstrating that our current CNC Router controller knows when I’m using cheap material, as it let these ones cut without incident).  With those on it looks the business:


Not bad for a first go at designing with folded metal!

However, although it looks the business, there’s a few things the prototype indicated I need to tweak. The main one is that the front fold isn’t quite perfect, and so having the end-caps perfectly flush with the metal doesn’t work aesthetically, as they highlight the slight variance. I’m informed that folded metal like this is never absolutely perfect, and you have to allow for little variations like this - sometimes with a mallet ;) However, here I’ll try to adjust the design of the end-caps to make this acceptable in the design. There’s also a few machine marks I’d like to see if I can get removed at the production place, as although I can file them out, I want the production place to also powder coat them before shipping them to me for the planned production run. Before I respin the end-caps I’ll get the guitar cable jacks wired in and pedals mounted so I can check for any other niggles by actually using it.

But for all those niggles, I consider this Achievement Unlocked! I’ve never fabricated things in metal before, and this turned out better than I had any reasonable right to expect for my first go. This opens up the door for other things down the line: for example, if I wanted to make more amps I can now make my own chassis to match my design rather than (as I did last time) building my design around an existing chassis which changed the vision I had quite substantially.

I did find a little time to keep plugging away with my trying to re-learn electronics. I’ve been struggling to get my IO-expander chips to play ball, but didn’t get very far due to my push on contract work. I did however make some strip boards for the relays I want to use with my pedal switcher, as they don’t mount on the breadboard directly.

A week in the shop

Apologies for the lateness of the weeknotes, contracting work has kept me rushed this last few days. But, the week notes must go on: here’s what I did last week.

After the previous week’s setback with the CNC router, I decided to just use the slightly damaged pick guard I had made and spent the better part of a day putting together most of the rest of The Clydesdale. This was partly just to check everything else was okay and there were no more surprises waiting in store as I brought all the bits both made and bought for the guitar together, but it was also a bit of a cathartic process for me to let me see the guitar looking like a guitar.


As is inevitable on a project that goes wrong so many times and drags on long beyond what you expected, this guitar has become something of a weight on my shoulders and mostly a thing that brings me negative emotions, as I view it as a series of personal failures leading it to be over six months behind schedule. Seeing it put together like this though helped remind me why it’s worth all the pain: the guitar just looks beautiful. The dark crimson stain sets off against the cream pick guard just right, the birdseye maple neck with the wenge fretboard is wonderfully rich in texture, and all the bits hang together just right.

I was going to solder up the electronics and string it up, but the Mustang design on which this is based is quite fiddly to do wiring wise and so I’d rather just wire it up once (when I have the correct pick guard) rather than do it now and then have to dismantle it when I replace the pick guard. But for now it was motivational to see it in this form.

A tip I learned whilst putting They Clydesdale together that I didn’t know before: how to shorten screws reliably. When you get pickups they have to come with long screws to allow for whatever mounting you might use, but I find then that they’re too long for the cavities I make in the body for the pickups, and so I have to cut them short with a hacksaw. This is a fiddly process, but a friend of mine (thanks Graeme!) explained his trick to getting reliable cuts on the screws: use two nuts to create a guide for the hacksaw blade.


This lets you get the position right and fixes it so that you don’t lose your place when you measure and then go to the vice for sawing. It also helps keep the ends neat by containing the material in something, so you don’t have ragged ends of your bolts. You can additionally sand the ends whilst in the nut for a better finish.

To do the setup for The Clydesdale and the prototype offset I finally ordered a proper set of nut files. Nut files are really quite eye-wateringly expensive, and so until now I’d been getting by with a set of the blowtorch nozzle cleaners, but whilst they do get the job done, they’re slow and frustrating to use. I think at this stage I want to be making things easier to get right rather than fighting with tools still. I do enough of that with the CNC Router :)

As I mentioned in the last weeknotes, I decided that I needed to rethink my guitar building plans for 2019. Even once the CNC Router is back online, I don’t think I’ll trust it for anything complex for a while, so I want a simple design that I can make using templates and the hand router, and nothing too complicated. At the same time I want it to be related to my future designs, so I’ve come up with the following design for my next guitar builds once The Clydesdale is done.

Screenshot 2019-01-09 at 16.20.13.png

Whilst I had bigger ambitions for the next set of guitars, I’m still quite pleased with how my more complicated design has made the transition here to something simpler, but still has elements of what I wanted. This particular example is a baritone scale length with a reverse headstock, as that’s what the customer was asking for, but I’ll also do a conventional scale length version to, with a either a reverse or regular headstock depending on the preference of who’s the customer will be.

I did a quick 3D print of this and sent it off to my brother who spec’d the baritone and his feedback was that he’s happy with the shape, which is top news. 


So the plan for this will be to make some MDF templates, then make the body and neck using the hand router and using a rasp for the comfort carves. Fingers crossed that this’ll move me forward more quickly in the first half of 2019 than I did in 2018.

It was quite nice to spend a bit of time in CAD again: it’s a technical challenge that I quite enjoy. I’m not alone in that, as the third Fusion 360 Show & Tell session I’ve organised at Makespace ran this last week, and we had a good turn out yet again with people sharing their tips and tricks on how the designed made made stuff.


It’s been quite a nice community event at Makespace, and we seem to be meeting my aim for this meeting that everyone leave with at least one bit of knowledge they can apply to their next project.

Related to that I’m looking forward to engaging with another community of makers up at DoES Liverpool: I’m going to be back up there for other reasons at the end of the month but am using the opportunity to make good on my promise to run the Fusion 360 training course I run at Makespace for their community. As DoES has a different set of equipment and different kinds of activities going on, I hope for me this is a way that I can find another set of people who’ll in future inspire my design and making process as has happened at Makespace.

The other thing I did was spend a bit more time on the electronics for my pedal switcher design. Slowly managing to remember bits of electronics, but slowly :)


Still, with other things blocked at the moment, it’s been a good mental exercise to keep me moving forward on this guitar side of the fence.

A frustrating start to the new year

I’ve been putting this week notes off as it’s been a frustrating week, but the point of these notes is to show the good with the bad, so let’s get to it.

As discussed last week, having diagnosed the latest fault with the CNC router down to the fact that it didn’t like one particular file I gave it, despite being valid, I generated the same tool path with slightly different layer heights and when I tested that on air, it all worked fine. Thanks CNC Router. 

So, I sat down to route the pick guard once again, but this time I had a more conventional failure, which left me with an almost perfect pick guard but with an annoying ding in it. When cutting out the holes for the pickups in the pick guard the the piece to be removed, which should have been secured by double sided tape on the rear, came loose, which then hooked on the router bit and managed to get in the way:


This caused the bit to deflect, making the edge there slightly less straight than it should be:


The pick guard is otherwise fine, but the professional in me sees this as unacceptable to ship.


So another failure, and I’m beginning to feel very cursed right now. The fix here is to not rely on the tape alone - I should have put a couple of screws in the bit that came loose - but for before now I’d managed to get away with it just using tape. To top it off, before I got time to cut it out again, the CNC Router pendant’s USB port broke, so now I’m without CNC Router until we replace it.

As the kids say, FML.

All in all, a frustrating week, which is why I didn’t really want to write up these notes. I’d set myself the goal to finish The Clydesdale by xmas, then by new year, and each time I hit yet another problem.

However, rather than just stop, I do have a pick guard that is the right shape and size and has the right holes in the right place, so what I’ll do this week is finish the rest of the guitar with this pick guard and then when the CNC Router starts working again I’ll cut another.

And when will the CNC Router be fixed? Well, Makespace has ordered two new controllers to try, and they’ll turn up mid Jan, so fingers crossed one of those will make us happy.

Given the frustration and given I was still trying to spend the new year at home whilst my other half was around more, I did some more playing with electronics. I actually did two years of electronics at university (over 20 years ago for those counting), but have not used it since (whilst I have done on-chip design since then, that’s a very different kettle of fish to playing with capacitors and resistors). 

My little project to help me relearn electronics is to make myself a pedal switcher, as at 6 pedals I have enough in my chain now that with it all “off” I still have a notable change in tone (doesn’t help that three of my pedals are buffered).

Thus, thanks to the advice of my friend Jason (who I helped with his Nixie Clock back in the summer), I got myself an Adafruit HUZZAH32 microcontroller and a bunch of other parts to let me prototype the bits I’d need for a switcher: an I/O expander chip to let me control more things than the HUZZAH32 will control directly, some latching relays, and some transistor arrays to let me power those. 


Early days, bit slowly getting there with the design, here I’ve got everything hooked up bar the relays as they don’t fit onto the breadboard here, I need to make a small board with stripboard with those on. 

A nice distraction from the woes in the workshop.

So, with 2019 arriving and the guitar building in 2018 not having gone anything like as well as I’d hoped, I think I need to reset my expectations. I tried to push along with the guitar building with the assumption that I could do a lot on the CNC Router and that just isn’t the case. Even with a fully working CNC Router I think it’s not a tool designed for quick one-off productions: either it’s something you labour over a lot time wise for a one-off that can be made no other way, or you want to do some test pieces and then never change your design and make multiples of them. But I’m not making enough guitars that I’ve hit that point, so I need to trying to use production techniques that suit the fact I’m making one off guitars for people or one-off test guitars to get me to that small volume production place.

I had designed some ambitious guitars for this year, which used both carved tops and angled headstocks, but I think committing to those would be foolish at this point, they rely too much on the CNC Router as a tool for making the guitar not just templates to let me build guitars by hand. Instead, at this point, I want to be making templates and using a hand router to generate the guitars, and designing to match a more traditional workflow given what I have access to. I just want to make some simple guitars this year that let me regain momentum and having the satisfaction of shipping. 

I’ll finish these two offsets, and then I’ll switch to making a sort of Junior version of the guitars I’d hoped to make for 2019: so flat tops, hand carved contours, and no angled headstocks. On one had I’m again frustrated, as in my head is this guitar I want to make and play, and now that’s a 2020 project, but on the flip side I just want to make guitars and see people play them, and that’s more important. So here’s to more wood being turned into music this year.

An xmas weeknotes

It being xmas this week there wasn’t much time spent in the workshop itself, but I did get some bits done. 

Just before xmas the replacement material to make the pick guard for The Clydesdale guitar turned up (two sheets, just in case), so I nipped into the workshop to have a go at cutting it again. Given I had all the g-code generated for the CNC router to make the pick guard I was going to just re-run it all, on the assumption that the CNC router had just glitched as was demonstrated on previous failures, but paranoia got the better of me and as a precaution I went back to the g-code for that path that failed and re-ran it on the machine with no material (running it “on air” as people like to say) just to convince myself it was a glitch (when the CNC router previously destroyed parts running the same g-code on air had just worked, strongly implying it was a glitch in the machine).

When you cut air on a CNC Router there isn’t much to look at :)

When you cut air on a CNC Router there isn’t much to look at :)

Turns out it was a good job I did this, as the machine did the same erroneous cut as before with this g-code! The g-code itself I’m convinced is valid (and others have reviewed it and said the same). In fact, when the CNC router makes the incorrect cut it is on the final layer of five (the material is 2.5mm thick and I cut it out in five passes, each just taking off 0.5mm), and it fails despite the fact that the exact same g-code is executed for each layer (I took apart the g-code file and compared the section for the failing layer with the one immediately above and it is byte-for-byte the same g-code).

I tried repeating the experiment multiple times, changing the feed speed of the CNC router, the origin offset, and even power cycling it on and off for a period of time, but this valid g-code file will fail 100% of the time.

This is both good and bad, for obvious reasons. Firstly it’s good, when something goes wrong it’s always good to be able to repeat the failure so you have a test case to show that you’ve fixed it. When in the past the machine has failed once and then never shown the error again it leaves you nervous as to when it will next strike. But the bad is that here there is no valid reason the machine should fail like this, so the machine is wrong, consistently. I suspect I can work around this, but it’s proved once and for all that the machine controller is wrong and needs replacing before I do any more expensive work on it.

Unfortunately all this meant I ran out of time to actually cut the scratch plate, so that’ll be this weeks top priority. I’ll regenerate the tool paths from Fusion and run them on air before trying to cut them on the CNC this time.

On the tool replacement front whilst the solutions I was looking at last week seem okay, I had a chat with one of the Makespace directors, and I’m mostly unconvinced any of them will work in the Makespace environment. Here we have a lot of new people come in who haven’t used kit like a CNC router before, and everything I tried just felt too flakey to be put to that purpose. Instead we’re going to investigate more embedded controllers again, such as the Masso CNC Controller.

That’s not to say people shouldn’t use Grbl and tools like Universal G-Code Sender, but just you need to understand what you’re doing with those tools more than you would with an embedded pendant solution like the one we have been using, where there is just less to go wrong, and less to reset when you get confused.

Whilst away from the shop I did sit down and try to get a couple of guitar neck designs done that I’d been meaning to do for a while: one simple and one complicated.

The first was working out how I’m going to make a neck with an angled headstock given the limited set of tools I have at my disposal. The new guitar design I’ve worked on for 2019 is based on a symmetric body design, so I really want to switch to a symmetric neck design, and I’ve gone for something that looks a little more like the Gibson/PRS style, compared to the inline headstocks I’ve been doing until now.

Screenshot 2018-12-31 at 14.01.45.png

Rather than make the neck from a single bit of wood, which would waste a lot of material, I want to make it using a single bit of wood that’s split at an angle and glued back together at the neck/headstock join, what’s called a scarf joint. In theory there’s many ways to do this, but all the obvious ones require tools I don’t currently have. For example, we have a band saw at Makespace, but it’s not that good quality wise - best for roughing up planks not getting precision cuts like I’d need for this joint. We also have a mitre saw jig, but it won’t go to as shallow an angle as I need here (10˚). 

Thus in the end I’ve come up with a slightly harebrained scheme that involves CNCing out the two parts of the neck, and then using a complicated set of jigs to glue them into position. 

Screenshot 2018-12-31 at 14.03.24.png

The positioning is key here, as there angles and shapes make it hard to align without some sort of jigs, and the obvious clamping surfaces are not straight on to the plane of the join, so there’s a risk that the two parts will slide apart once clamped, thus it all gets very complicated. I’ve sat on this problem for several months now, and I finally decided to just ask for help from a couple of more experienced wood workers I know, and they agree that my harebrained scheme probably is the best I can do with the tools at my disposal. Once The Clydesdale is done I’ll probably give this a go as a novelty. 

The other bit I did was playing with new inlay designs, just using my older neck design as a template for it. I do in part still want to replace the neck on The Blues Deluxe t-style so I can feel happy selling it on, as (as I’ve mentioned before here) the neck warped when glued and whilst at the time I managed to save it, I don’t think its up to the standard I’d expect today.

Anyway, I clearly was missing video games, as the design I came up with is a slight mashup based on game controller arrows to complement the chevrons on the strap that guitar has:

Screenshot 2018-12-31 at 14.05.46.png

I have to say, for what should have been a simple design, getting the arrow inlays to work in Fusion 360 was quite a pain. I had to specify lots of constraints so that when I copied and moved the design around the neck each time it’d stay in the right shape, and I could define a proper midpoint for positioning it between each pair of frets.

Do you want some constraints with your constraints?

Do you want some constraints with your constraints?

I’m sure there must be an easier way than what I did, but I couldn’t find one, and at least that got me there in the end. Not sure this is the final version of this look, but it’s nice not to have the same old circles for a change.

And that’s a wrap for 2018! I’ve started a year in review post, but for now let’s just say 2018 did not go the way I planned, but I learned a lot along the way. The trick will be turning that learning into momentum in 2019 and getting more guitars made, rather than just reeling from setbacks as I’ve done this last year. Good luck with whatever you’ve got planned for 2019!

A week in the shop

My aim this week was to get most of the basic bits of The Clydesdale finished, but unfortunately it wasn’t to be, and this the week turned into a lot of trying to work out how to swap the brain on the CNC Router before it crosses me again.

After the success of making a custom pick guard for the prototype offset build last week, my plan this week was to make the pick guard for The Clydesdale, and then I could set about mounting all the rest of the hardware, getting to a point before xmas where all the was left to do would be setup work. So on Monday I sat down at the CNC router and set it to work on pick guard for the Clydesdale. This one is slightly more complicated than the one for the prototype, due to the pickup mounts needed another diameter hole (meaning an extra tool change) and the slot for the three-way selector switch needing a smaller end mill: all in this pick guard required 6 tools rather than 4.


All was going well until it was doing the final pass on the outer contour when the machine decided once again it really didn’t like my design and it would be much better if it just cut the side off :(


I’m not a superstitious person, but I’m finding it hard not to agree with my friend Graeme that this machine knows when I’m working on this customer’s guitar: it’ll be okay when I do the prototype test pieces and then I sit down to work on The Clydesdale and then it decided to play up. The real pain here is that I didn’t have any more cream PVC material to cut another one, and it being the week before Christmas getting replacement was very slow. Although I immediately ordered replacement material, it didn’t arrive until Friday by which time I was getting ready to wrap up for xmas along with juggling some last minute contract work. Obviously this was hugely disappointing.

What do I think went wrong here? My current theory is that the controller being cheap means it’s struggling with floating point numbers occasionally. The g-code language used to describe what the CNC-router should do is full of floating point numbers, and computers always struggle with floating point numbers a little, as they can’t represent them perfectly. For example, you can sometimes get a computer to add 1.0 and 1.0 and it’ll give you 2.00000000001. A friend took a look at my g-code and observed on the g-code for my pick guard had the curved edges represented as a lot of very small lines rather than as a series of larger curves. If you have bug numbers than floating point inaccuracies in computers don’t matter much, but if you have lots of small numbers then these inaccuracies can start to cause real trouble, and it could just be bad luck that the controller (which we know isn’t built to the highest standards) just got its maths wrong at that point. 

I do have more material now, and I will try and get the pick guard cut again when I get back from xmas obligations, so I might yet get this guitar built before the year is out, but it’s going to be tight!

After all the other failures we had slowly been planing to replace the controller on the CNC router at Makespace. I hadn’t rushed this as my assumption was it was the more complex designs I do that were causing it to fail, but given the pick guard here was a relatively simple design I decided to refocus my week (given I was no longer fitting hardware to The Clydesdale) on moving that upgrade process forward.

Adrian, one of the Makespace directors, had built a test rig that let us try out new controllers and related software; in the summer we’d spent a day taking the CNC router apart and putting it back together only to find the replacement controller we had at that point didn’t work, so a test rig like this make finding a new controller much easier.


Adrian’s done a fantastic job with this rig: it features three axis motors and motor controllers, a bunch of physical switches for the various triggers that would be on the actual machine, and a display to show how fast the spindle would be driven. To top it all, he’s mounted it nicely up and labelled it all - a top job.

My task then is to figure out the software side of this. On the board currently is an Arduino running the popular hobbyist controller software Grbl. But Grbl only does half the controller job: it expects to be fed by some other g-code reading tool on a PC or similar device and then it will take commands from that and send them to the motor controllers etc. I tried a lot of bits of software, but the ones showing most promise are Universal G-Code Sender, and Easel by Instructables.

When assessing the software I wear two hats. Firstly, as a guitar builder I’m looking to see whether the software can cope with the complex designs that am generating these days with complex curved surfaces etc. Secondly, as someone who trains people on the CNC Router at Makespace I’m looking for a tool that is easy to get started with and will easily do the simple 2D shape cuts that most new members actually want to make. My research makes me think I can’t solve those two use cases with one bit of software, which is why now I’m looking at two different solutions. 

Easel is quite a nice bit of easy to use software if all you want to do is cut out some simple 2D shapes. It has a nice visualiser of what you’re going to cut, and when you go to machine it has a wizard that takes you step by step through getting everything ready. The only issue I’ve had this week is that although it acknowledges the z-probe on our test rig it doesn’t seem to want to use it, so I need to find a way to get that to work.

Screenshot 2018-12-24 at 12.26.51.png

Universal G-Code Sender has a much more complicated UI and relies on you knowing a lot more, but at the same time you can then do a lot more with the tool.

Screenshot 2018-12-19 at 18.42.00.png

Neither tool is perfect - and for all its faults the current controller we have for the CNC router has a robustness about it that I feel is missing from both these software solutions. If anyone has any recommendations for tools in this space they love please do let me know (Grbl based or otherwise).

That said, I’m getting to the point where I want to try these tools on the actual machine, but there’s still a couple of things I need to get comfortable before we tear the CNC Router apart again.

In unexciting workshop tasks I fixed my headphones in preparation for carrying on my guitar practice when we visit the in-laws for xmas week. As often is the case the wire had broken internally where it entered one of the ear pieces, but thankfully it has a 2 m cable on it, so I just cut it off and soldered a new connection on an unbroken bit of wire. 

Then, to try and give it better chance of surviving I replaced the old strain gauges with bits of orange Sugru; at least now I’ll be able to spot which headphones are mine in the workshop :)

The final act of luthiery before xmas was going to the pub with a couple of other local Luthiers: Matt from Fidelity Guitars and Jamie from Swannell Guitars. It was a nice evening and a reminder that I spent too much time head down in the workshop and not chatting to others to help keep me motivated. Something to work on in 2019!

A busy week in the shop

This week was fairly busy in the shop as I try wrap up two guitars, and had another one come back in briefly for a repair that turned into an upgrade.

The Clydesdale offset build has properly entered its assembly phase. This week I did the cavity EMF insulation, made a prototype pick guard, and finally fitted the neck to the body,.

All the guitars I build have their internal cavities lined with copper tape to provide protection from radio noise for the pickups and wiring. The end result looks stunning, but is never actually seen by the user, as it’s all hidden away inside - a hidden inner beauty. This stage took slightly longer than I expected due to running out of tape halfway through, but thanks to Amazon Prime was completed a day later.


Cavities lined, I then did a quick mockup of the pick guard in cardboard to ensure all the sizing was correct for both placement on the body and that the holes for the pickups are correct.


As I mentioned last week, I’ve not had much luck in the past making custom pick guards on the CNC router, but for this guitar what I have in mind really needs to be done that way, so before I made the one for The Clydesdale I wanted to try cutting another one as an experiment first for a different technique, which I’ll explain below.

Finally, I also mounted the neck to the body this week, taking what has been two parts for so long and making them into one. To simplify the CNC process at the start of a build I don’t cut the neck on both sides using the CNC router, just from the front, which means I have to make the holes for the neck screws by hand. It’s not a major imposition (people have to do this all the time when they buy a new neck for their guitar), but given I do use an initial CNC roughing pass this sees a bit silly, and something I’ll rectify in future builds to save time. Anyway, it took me an hour or so to make sure these were lined up perfectly and straight (at this point the fretboard is rounded remember, so ensuring everything lines up isn’t just a matter of whacking the neck on the drill press and going for it). 


This picture makes me very happy though. The end starts to be in sight!

I mentioned last week that I had finally set up the bridge for the Prototype Offset guitar such that it would stay in tune when you used the vibrato unit. This made me happy, but I decided I wasn’t that pleased with the pick guard I’d made for it previously. Earlier in the year my attempt to made a pick guard on the CNC router had gone a bit wrong: the PVC material they’re typically made from did not sit flat (but to being quite flexible) and thus my attempt to make countersunk holes for the mount screws was a disaster. As an alternative at the time I just made one out of a duo-tone acrylic I had using the laser cutter, but now I looked at the finished guitar it just looked not up to the standard of everything else. 


Thus, I decided now was time to try again, applying all the learning I’ve had on the CNC router since. The problem I faced is that if you make an angled cut on the CNC router, if the material isn’t perfectly flat then you’ll get different amounts of material removed depending on the height of the top of the material from the bed, so I need everything to be as flat as humanly possible before I start cutting.

The first thing I did before doing anything with the pick guard was to level the sacrificial bed on the CNC Router itself to make that perfectly flat again. It needed doing anyway (if you recall I last did it back in late July), and this was a motivator for me to finally get around to it. This time was much quicker, having upgraded the CNC router recently to take 1/2” shank bits we now have a 2” diameter facing off tool, rather than the 1” one I used before.

Once the bed was levelled I took my PVC material and attempted to make sure it was perfectly flat on the bed. Just screwing it in at the corners isn’t enough for a material this flexible, so I took two approaches to this. Firstly, I covered the underside of the PVC with double sided sticky tape, and stuck it to the bed, which gave me overall confidence that things would be flat. However, I didn’t quite trust the double sided tape to hold up to the CNC router’s tug alone, and so the second part of my strategy was I drilled the holes for the screws that would hold the pick guard on the guitar before I did any other cuts, and then I used those to screw the material to the CNC router bed just as I would on the guitar! These screws follow the chamfered edge and gave me as good a guarantee as I can get that this bit of the material will remain flat, and the screws themselves are small enough they’ll be clear of the cutters by a safe margin. As an added bonus, this also meant I didn’t need to use tabs when cutting the material out either, meaning no manual sanding tabs off after cutting.

Plan down, I assembled the bits I needed for the job, can went to work: a 2mm bit for the mount holes for the guard itself, 3.5mm drill bit for the pickup mounts, a 2.5 mm end mill for the contours, and a 30˚ V-cutter to chamfer the edges.


Here you can see the results of the first pass, the material is now properly anchored down by the same screws I’ll use to attach the guard to the guitar.


And the end result was this:


Note the bits inside the pickup holes haven’t come loose despite not being held with tabs: it turned out the double sided tape was quite effective, and the free bits did stay in place. I then had to take the guard off the bed, remove the protective film from the top which was now frayed at the edges, clear up the edges a little and peal off the tape (and wash off the remaining residue. Then it was a little work to swap the old pick guard for the new one, and the guitar now looks so much better!


I’m really pleased with how this has turned out, and also with the fact I’ve got custom pick guards licked after several failed attempts. This coming week I’ll attempt to repeat this success for The Clydesdale.

This guitar here though is now just waiting final setup before I list it for sale. If you fancy a hand built offset guitar, fitted with top quality components (House of Tone pickups, a Mastery Bridge, fitted hard case, etc.) , this get in touch. It’ll be going up on Reverb shortly I expect, priced at £1500 plus postage. 

The very first guitar I built for myself still sees regular usage (indeed last week went to Rotterdam with me), and I was sad to note that the volume pot was starting to fail this week: mostly it’d be fine, but occasionally you’d whack the volume to max and it’d cut out until you rolled it back off and up again. Thankfully it’s a simple enough fix to replace the pot, and was finally the excuse I needed to give this guitar a coil split option on its humbucker.


As I’ve probably mentioned before, a humbucker pickup (the silver rectangle just under the neck in the guitar above) is actually made from two pickup coils, rather than just one as you might expect (and is common for a lot of pickups). The idea is that the two pickup coils are wound in opposite directions, so that radio interference picked up on one is picked up as a negative on the other and when you combine the signal from the two it cancels out (and thus it eliminates the “hum” you get on single coil pickups, thus the name hum-bucker).

In addition to the noise being cancelled out, because you have two coils working together you get a stronger output from a humbucker compared to a regular pickup, which is good if you want heavy rock tones, but there are times when you’d like something less juicy from your guitar. One way to achieve that is to put in a coil split, where you electrically cut out one of the coils in a humbucker and just use it as a single pickup. You risk getting the hum back then (you can see why I do the copper lining above now), but you’ll get a second tone out of your one pickup; and the more tones you can get out of a single instrument the more versatile it is, which in my book is a good thing.

To achieve a coil split you generally need your humbucker pickup to have an extra pair of wires coming out of it already to support this, and the Gibson 490R pickup in my blue tele did indeed have wiring to support this. Thus, all I needed to do was add a switch to let me toggle that extra coil on or off. What’s this got to do with the volume control you ask? Well, the conventional way to add this switch is to have a volume knob that will pull out to switch the second coil out, and push in to return it to its rightful place - so now that I needed to replace the volume control it was time to make this change! I already had the right push/pull switching pot in stock, so all I had to do was remove the old one and install the new one.


You can see here the previous wiring, and the new pot beside it with the extra solder lugs on the bottom of it to let me do the switching. My soldering must be getting better, as doing the swap was a lot quicker than I remember it was putting this guitar together back in mid 2016 when I just got started. I’m really pleased with the results: the new tone on this guitar is still clearly related to the humbucker sound, but if I want to play something a bit more nuanced then I can, but I can still run it as originally intended when I want to crank up the noise. A simple mod that gives you a bunch of flexibility. 

If you’re in the Cambridge area and would like a mod like this for your guitar, do get in touch!

On the topic of circuits, it’s frustrated me that I don’t have a proper way to record existing circuits I’ve made for documentation purposes (like those in the guitar or in the amp I made) or a way to record new circuits that I come up with, so I finally sat down for a little bit and started trying to learn Autodesk Eagle. It’s early days, but I’m starting to get my head around it, despite it’s quite archaic interface. I used to work for Intel a long time ago, and back then hardware design tools always seemed to lag substantially behind other domains in terms of usability: it seems nothing much has changed in the decade and a bit that has passed since then.

Finally a little word of caution if, like me, you find yourself taking your Apple laptop into the workshop. I noticed that my laptop wasn’t charging properly at times, and that the magsafe power adapter wasn’t sitting in it’s socket quite right. I finally had a look at the socket, and it turns out it had picked up a bunch of iron shavings that had stuck to the magsafe port!


Getting them out of their wasn’t easy, as it turns out the magnet in the magsafe port is really quite strong, but once I fished them out the laptop worked a lot better :)