Pre-Wired harness common questions!
I've been proudly making, developing and installing my pre-wired guitar harnesses since the beginning of the Home of Tone back in 2015 (time flies when you're having fun right!). Although I feel I do my best in covering as much information as possible already across the various product listings, fitting guides and wiring diagrams and more, I thought it might be helpful to put together this article answering some of the common questions my customers ask either prior to ordering or prior/during installing in your guitar. I'm going to delve into a variety of questions for a range of the harnesses, but I'll try to do so in a clear way to help you find the info you are looking for!

Guitar wiring helpful tips

What soldering iron and solder should I use when installing my harness?
- IRON - Most hobbyist soldering irons we have in our tool cupboards at home are up to the job of helping you fit your harness. For working on guitar electronics, I personally recommend a 40w iron, this will provide ample working temperature for the task at hand. A variable temperature iron may be additionally helpful as you'll find you won't require as much working temperate for pot lugs, but need much more for soldering grounds for example.
- SOLDER - For commercial product reasons, I have to use lead free solder. I personally use Rapid brand lead free on harnesses and it’ll be what I used on your harness too, so if you’re deciding which solder to use, I’d happily recommend using Rapid lead free.. It’s available in small lengths too meaning you won’t necessarily need to buy a huge reel of it unless you're happy to stock up for future projects. Lead free solder might be a little tricky to use if you haven't worked with it before or are used to using leaded solder. So perhaps make a few practice solder joints prior on old components for example. Leaded solder works to a lower temperature than lead free so it's worth practicing with first if not used to it, particularly when soldering ground wires to the back of pots for example which are somewhat sensitive to excessive heat. Get a feel for the melting point, how it flows and how it 'takes' to the surface.

Types of guitar pickup wires

My pickup wires look different to what is shown on your wiring diagram, which wire is which?!
For my wiring diagrams, for consistency and simplicity sake, I show traditional 2 conductor wires. But what are the different types and which do you have?
- Types of pickup wire - There are two main types of wire seen on a pickup, two conductor or 4 conductor. Two conductor is perhaps the most common on vintage style pickups and for this you'll more than likely see two individual wires (often white and black) or a metal braided wire (silver metal braided covered wire with a black covered wire inside). These are nice and simple really, one wire is your 'hot' lead, the other is your ground. There are sometimes differences in the colours used which I'll get to in a moment! If you're ever not sure about which wire is which, I would recommend to consult your pickup manufacturers specifications.
4 conductor pickup wires are most commonly seen on humbuckers, as it enables a wealth of switching styles to be achieved such as coil splitting. Now this unfortunately is where it gets a little bit complicated as sadly not all pickup manufacturers play by the same rules here and each company uses a different colour scheme/coding for their pickups. Below is a really helpful diagram by Seymour Duncan, which shows a variety of pickup brands and how they colour code their 4 conductor pickup wires. But again, I would highly recommend you check out your pickup manufacturers specifications before diving into your install.
If you've purchased McNelly Pickups from me with 4 conductor wiring, you'll find the colour code diagram over on our wiring diagrams page or by clicking HERE if you're already reading this article!

Guitar pickup wiring colour codes


Will my existing control knobs fit the new CTS pots?
Now, this one although might seem otherwise menial, is a really important question as trying to force fit the wrong sized control knobs or even the correct sized ones in some cases, onto the pot can completely damage them. So please do take the time to read through this one as it could prevent some headaches after everything is installed and a simple control knob ruins your hard work!
I use across my harness range, USA spec pots which for split shaft versions measure 5.95mm with 24 splines, and 6.35mm for solid shaft versions. 
In most cases, the original control knobs on import type guitars such as Squier or Epiphone for example, will have metric sized control knobs suited to smaller pot shaft diameters. These items simply won't fit onto the larger USA spec pots I'm afraid. If your guitar is a Fender or a Gibson, USA made guitar then chances are your original control knobs will fit onto the new harness pots just fine. But it is still VERY important to ensure care is taking when installing those push-fit control knobs as damage can still be done to the pot if fitting incorrectly believe it or not. 

Fitting push-fit guitar control knobs

- Fitting push-fit control knobs helpful tips - 
Push-fit spline type control knobs are designed to be a snug fit on the pot shaft, but if forced on can cause extensive damage to your pots. Gently push them onto your pot shaft first. If it feels too tight, to the point that excessive pressure is required or that you get a feel that you are forcing it on, then stop immediately and remove the control knob. With the control knob removed, slightly pinch the split shaft of the pot together like shown in the above photo and re-fit the control knob, repeat if required until fit is perfect. It should push on fairly easily but with enough pressure to feel like it has sufficiently gripped the pot shaft and your control knob will stay put. If you have import/metric sized control knobs that suit 18 splines these will NOT fit the CTS pots I used for my harnesses, they’re too small and will damage your pot in forcing on to fit, so please do not attempt to fit these to the harness.
They are of course super super easy to fit, but surprisingly super easy to break your new pots in doing so as well. I advise to take care when fitting to avoid any damage to your pot. Nothing worse after spending time fitting your fresh harness, string back up etc and finally end up damaging your pots by forcing the control knobs on afterwards.
Solid shaft pots aren't quite as much of a worry, as it will be pretty obvious if the control knob doesn't fit on and you'd have to be doing incredibly well to try and force fit a control knob that is too small. Solid shaft pots I use measure at 6.35mm for reference and the control knobs usually suitable for these variation of pot are those with a small grub screw to retain them. You'll see these on most Telecasters for example. 
If you want to use grub screw retainer type control knobs to your guitar which has split-shaft pots, you can still certainly do that but you will require some conversion sleeves. I stock some brass conversion sleeves which slide over the 5.95mm split shaft pot, and convert the out diameter to 6.35mm essentially making it a USA spec solid shaft pot. With these installed you'll be able to use any 6.35mm suitable grub screw retainer type control knob.

Split shaft to solid shaft guitar pot conversion sleeves

If you are looking for a new set of control knobs for your harness, I stock a small selection of plastic and metal control knobs in a variety of styles but ALL suitable for the CTS USA pots I supply and use. As I don't stock any import style, metric pots, I don't stock their matching control knobs either so no risk of ordering the wrong ones from this website for your new home of tone harness.



My jack socket hasn't arrived pre-soldered, why is that and how to I install it?
Unfortunately, due to the restricted control cavities and wire channels on some models of guitar, like the Strat or Les Paul for example, I can't pre-solder the jack sockets for those harness kits. If I did, you'd have to de-solder it and re-solder it which is unnecessary extra work! So inside your harness box, you'll find your new Pure Tone brand multi contact jack socket supplied separate ready to install after the wires have been passed through the relevant body wire channels. I sometimes see photos of other brand pre-wired harnesses showing strat jack sockets already soldered to the wires and my heart sinks, knowing the receiver is going to have to de-solder and re-attach that jack socket when they come to install their new harness. You shouldn't have to do that, so I pre-solder everything I physically can harness end, and allow you to fit a brand new jack socket to nice new contacts when you have passed the wires through the body wire channels.  
A standard mono jack socket has two solder lugs, one for your 'hot' output and one for your ground connection. If you look closely at your jack socket, you will see one of those lugs is connected to the 'tip', the portion of the socket which contacts the tip of your jack plug when pushed in. The other lug is connected to the sleeve, which contacts the ground/sleeve part of your jack plug when pushed in. I have written a previous blog article with info on how to solder a jack socket with a variety of commonly seen wire types on guitars and you can read that article HERE!

Will CTS pots fit my scratchplate/guitar body?
This is a really important question and one understandably asked a lot. The CTS pots I use across my harness range have a mounting thread diameter of 9.5mm. This is quite a bit larger than common import sized pots seen on Squier, Epiphone or other far east made guitars, which usually have a mounting thread diameter of 6mm or 8mm depending on type or brand used. So chances are, if you have a far east made guitar, you will need to widen the holes in your pickguard or guitar body depending on what type of guitar you have, to suit the larger CTS pots used in a new harness. 

Installing USA spec CTS pots on far east made guitar

To carry out this task, I recommend doing this using a step cutter. This is in my experience the safest method as it will reduce the risk of paint chipping around the hole if a guitar body mounted pot, I usually widen the pot mounting hole on pickguards or bodies, to a 10mm hole to comfortably suit and fit the CTS USA specification 9.5mm shaft diameter. A good technique is to tape off the stop point diameter required on the step cutter to avoid drilling to the wrong diameter hole, and carefully run your drill to ensure an accurately finished hole. Once this is done, you can final finish the hole to straight edges by running a regular 10mm drill bit through for the pots to easily fit through. IMPORTANT- I highly recommend that if you are not comfortable with doing this in any form, or importantly don’t have the correct tools, then please considering taking this to be done by a trusted professional guitar technician. It’s not worth the upset and disappointment in damaging your guitar!

Long or short shaft pots for my les paul

I have a Les Paul, will I require long or short shaft pots?
Without a doubt, the most commonly asked Les Paul harness question, so don't worry, you're not alone! As you can see from the above photo, there is quite a substantial mounting thread length difference between the two and that is basically down to the body cap or top depth differences across the Les Paul range.
Gibson are of course known for lots of transitional changes to specs from the golden era right up to the modern day built instruments. I have compiled a list of Gibson models which use either Short or Long shaft pots on the individual pot listing HERE But, if you're still not sure, the simplest answer is that ALL types of Gibson or Epiphone Les Paul will fit a long shaft pot, as you can adjust the two supplied nuts to suit the desired mounting height in the body. All Epiphone Les Paul's with exception of the Elitist model use short shaft pots.
If you're not ready to remove your old pots and measure the existing thread lengths, then hopefully the above info will help without having to touch any tools just yet. But do remember, if you're ordering or have ordered a harness through my website, feel free to send me a photo of the inside of the control cavity or a photo of the pot itself, hopefully I can help identify it for you. This isn't a faceless business, it's me here handling all orders personally so I'm happy to help guide you to the correct option for your Les Paul, whatever the model or where it's made. 
For your reference, a short shaft 500k pot has a thread length of 9.52mm and a long shaft 500k pot has a thread length of 19.05mm.

modern or 50s style

Whilst we're on the subject of Gibson's...
Modern style, or 50s Style wiring, what is the difference?
Honestly there is no right or wrong with this and it's really down to personal preference. So, 'which would suit my needs best?' you ask, and rightly so. 
The general consensus is that Modern wiring maintains the overall volume better than 50s style, maintaining volume when rolling down the tone pot for example, but it does lose some of the high end 'treble' frequencies when rolling down the volume pot which is where many players notice the difference in use. Although with the addition of a treble bleed, this is rectified and modern style can be the best of both worlds (so that's an option here too!). 
With 50s style, more treble frequencies are retained than modern style when lowering the volume pot, but the volume and tone controls work differently together and you can find that as you roll the tone pot down, you will notice the volume drop a little.
There really isn't a right or wrong, but hopefully the paragraph above helps in making the right choice for you. My modern style is ever so slightly different to other schematics you might see, and is based on the McNelly schematic which is actually inspired more by how a Telecaster is wired traditionally so hopefully that helps in some of those common modern wiring dislikes by some. But if you'd like to know which is the most commonly ordered harness, currently, 50s style definitely takes the win overall. It seems the Gibson vintage gear allure is too great to resist!

I am looking to install a harness into a 335, is it as tricky as everyone says it is?
Unfortunately, yes, you'll need to be sure you're patience levels are at their best for this one. Although honestly not a difficult install process at all, it can be time consuming and a little tricky due to having to feed the wires through the guitar's f-holes. For this I highly recommend due care and attention to ensure you don't damage the guitar's lacquer around the f-holes for example and HIGHLY recommend testing all of your connections and tap-testing the wiring all works correctly before spending the time putting everything back in there! If at all lacking in confidence to approach this task, I recommend taking your guitar to a trusted guitar technician to install your new wiring harness. 
There was a great article written by the tech inspiration that is Huw Price, for Guitar.com. HERE is a link to the article, where he shows a number of techniques when working on 335 wiring installs which might be of some help though!

What is the extra nut for that was supplied with my SG harness?
The thread length on a Switchcraft right angle 3 way toggle switch used on an SG due to the limited control cavity size, is rather shallow, so to allow it to fit through the body of the guitar along with the usual 'poker chip' rhythm & treble plastic piece, I supply with my SG harnesses a extended knurled nut. This is essentially a recessed/extended nut which makes it much easier to fit the toggle switch and allows it to be sufficiently tightened. I hope that helps!



What's the best way to test my my freshly fitted harness before putting all of the guitar back together and string-ing up?
This, although isn't exactly a commonly asked question, was something I've decided to include in this article as it might prove helpful to you when installing to prevent wasting time if a connection isn't right or unfortunately but not impossible, a component has failed. I refer to 'tap-testing' on a few articles on the blog, and by that I mean gently tapping the guitar's pickups after installing the harness and giving it an initial test. Spending some time soldering everything together, mounting it all back in, stringing and tuning up only to find something doesn't quite work right is disappointing. So, how do you give it a quick test before putting it all back together? I always just do a super primitive and simple 'tap-test'. When you have finished soldering all of your relevant connections, pickup wires and bridge ground wires etc, give everything a good once over, ensure the solder joints done by you aren't dry joints, they're nice and solid and everything is where it should be connections wise. Then without any strings on (if you have had to remove strings in carrying out your install for example), plug your guitar into an amp and turn it down to a quiet level as this process can be loud, then simply grab a screwdriver etc and gently tap the pole pieces of your guitar's pickup in the relevant switch positions. You can then check if the volume pot works as it should, if the tone pot works as it should and makes the tap sound result in a dull thud or a clear 'tap', run through each switch pickup position to ensure the right pickup is selected through all the positions. Just be sure to tap the pickups gently and to not leave the tool resting on the pickup's magnets for long at all. Just a quick, gently tap is all that's needed here. It might seem crude, but it's a great, quick way of checking the freshly fitted wiring functions as it should before spending time assembling the guitar back together. Really sucks having to take everything apart again! In terms of my solder connections, I take great care and pride in my work, and do double check all harnesses by looking closely and my solder connections to ensure they're not just neat, but solid and correct. I am only human though, I put my trousers on one leg at a time like everyone else lol! so I make sure I double check every harness I make before it's packaged up and sent to you. But I hope this quick tap-test trick helps you during your stage of the solder work and install. 

James' Home of Tone Pre-Wired guitar harnesses

What will be included in my harness and what components do you use?
I name my harnesses the 'Signature Series', mainly because after a number of years working on guitar wiring and making harnesses I've come to prefer certain brands or types of components and simply now use what I trust will be a quality replacement for your guitar. I use a selection of CTS 'TVT' Series +/-7% tolerance pots, Switchcraft and CRL switches, Gavitt USA made wire, tinned copper ground bus wire, pure tone multi contact jack sockets and currently UK made +/-3% tolerance capacitors. To see precisely which components I use in each model harness, you will find a run down of the exact specs in each product description.
You'll also find here what is included in your harness order. But it is worth noting here that I don't print off and supply the fitting guide or wiring diagram in each and every shipping box anymore as I feel it was an awful lot of paper being printed and potentially just thrown away. So I have created a great reference page here on the website which shows each and every wiring diagram suitable for every variation of wiring harness I make, along with the must read fitting guide at the top. You can find this wiring info page linked on my website or by clicking HERE too!If for any reason you're unsure of which is the right diagram for your harness, do please just drop me an e-mail/message and I'll e-mail a copy right over!

Will fitting a new wiring harness to my guitar make any difference?
Let's round this article off with the vital question, and an important question at that! The main reason replacement wiring harnesses are so popular for a number of brands, and a major part of my own business too, is because they offer a simpler way of replacing your guitar wiring if you have existing faults. But also some factory guitars have lower quality components which don't perhaps bring out the best in the guitar's pickups or operate unreliably too. I wrote an extensive article on this subject a while back here on the blog, and you can have a read through that HERE.
I am wholeheartedly proud of the quality of harness I make, and I personally see them as an upgrade or high quality replacement to install into your guitar. Without blowing my own trumpet too much here, the very best way I can share this best is by quoting some of my customer's e-mails and reviews left of my pre-wired harnesses as that to me is the very best example I could possibly give! 

Vince 20/07/2019 - "Hi James.....just wanted to send a quick message to thankyou for selling me a new guitar!!!!!!!!!!!. Seriously breathed new life into it. Installed the harness this morning and only just put the thing down.....very much appreciated"

Jonny 04/03/2019 - "Not only does James provide excellent customer service, but the harness I've installed feels like a significant improvement in my Japanese Telecaster"

Patrick 10/11/2019 - "I bought a telecaster harness to replace the original in my Squire Standard Tele. It arrived promptly and made a huge difference to the sound. James uses quality components. No more hisses or crackles. And the wiring looked great too"

Noel 29/01/2018 - "The difference is stunning and other people have commented on the tone transformation. I knew there would be an improvement, but not to this level! My Tele has turned into a beast! Many thanks"

Just a small selection of the many reviews left on the website or e-mailed to me by my kind customers. I hope this article helps answer some of the common questions, there are of course many more questions you may have before or after making a harness purchase so don't hesitate to e-mail and I'll do my best to help along the way. 

James

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