A classic Gibson design, the Les Paul Junior is thankfully also very easy to wire. Consisting of one volume and one tone control, the single pickup rock machine has become one of the world's most loved guitars. The versatility from a single pickup with a volume and tone control has gripped players worldwide. In this guide, we will show you how to wire the Les Paul Jr (which is also the same for the SG Junior) using our Les Paul Junior wiring kit. There is a wiring diagram at the start of the guide and we recommend you print it off and study it before starting.
To wire a Les Paul Junior you will need
- 2 x CTS 500k short shaft audio pots
- 1 x 0.022uF orange drop capacitor
- 1 x Switchcraft USA long threaded 1/4'' jack
- 1.5ft of braided cloth guitar wire
- 25-40w soldering iron
- Lead/Tin solder (60/40)
- 3.5mm diameter heat shrink tubing (12cm in length)
- Les Paul Junior wiring diagram
The first thing to note is that the Les Paul Junior is wired entirely using braided guitar wire. The volume/tone controls and the jack are all connected together using a single length of braided wire. The second thing of note is the capacitor - typically a Les Paul Junior will use a 0.022uF cap but as they often come with P90's, a 0.047uF is sometimes used. In this guide and diagram the capacitor is wired in the "50s" style which is preferred by many to the modern way of doing it as it acts somewhat as a treble bleed on the volume control (retains high end frequencies as it is rolled back) and the volume and tone controls become more interactive with each other. If you prefer the modern version, refer to the diagram at the end of the article - it is simply changing the location of the capacitor.
As is the case in the majority of our guides, the Les Paul Junior is another that is easier to wire outside of the guitar. The control cavity is small and it is too easy to burn either the wires in the harness or worse still, the guitar's finish itself. Therefore, it is ideal ot make a little jig to allow you to do the bulk of the work outside of the guitar.
Take a 10cm x 15cm piece of plywood, acrylic or sturdy cardboard and place it under the top side of your guitar - this allows you to easily trace the pot holes through the control cavity onto the card underneath. The idea is to replicate the inside of the guitar's control cavity. For official Les Paul Junior dimensions, the centre to centre distance of the two holes is 6cm. Having traced the holes you need to drill them to 3/8'' (M10) diameter to accommodate the CTS pots.
Next it is time to ground the two pots together using tinned copper wire. Start off by tinning the two lugs which need to be grounded (lug 3 of the volume control and the middle lug of the tone control). Also tin the back of each CTS pot by spreading a light puddle of solder around. Feed a single piece of tinned copper wire through both lugs and ground at each end. Refer to the video and the below photo.
Next, using your braided wire, push back the outer braid and inner cloth wire to reveal the inner wire - solder this to the output lug of the volume control (middle lug). This will run all the way to the jack. Solder one end of the capacitor to the same lug and the other end to lug 3 of the tone control the lowest lug from a birds eye point of view). Once done, feed a couple of cm of the heat shrink rubber tubing to cover the braid.
The braided wire will run all the way to the jack - however, we need to ground the outer braid to the side of the tone pot casing on the way. Braided wire acts as two wires in one - the outer braid is the ground, while the inner wire is the hot/live.
Tin the side and top of the tone pot casing by spreading a small puddle of solder in the area where you will solder the braid to. Then use your masking tape to hold the wire in place while you create a "bridge" of solder between the pot casing and the wire. Refer to the below photos.
Before we connect the jack, feed some more heat shrink tubing over the braided wire, leaving half a centimetre or so before arriving at the jack. Use a heat gun or lighter to shrink the tubing into place.
Pull back the outer braid, revealing the inner wire - this is what gets connected to the jack's output lug. The outer braid goes to the ground lug (the lug with the ring)
Unravel the remaining outer braid until you can twist it and snip it to leave a little ledge - it will wedge into the hole of the jack's ground lug and will be easier to solder.
Cut the excess leaving a ledge of 2mm or so - it will wedge into the hole of the jack's ground lug and will be easier to solder.
Connect the inner cloth wire to the jacks output lug and cover it a with a snippet of heat shrink tubing, then solder the wedge of outer braid to the ground lug.
There we have it - how to wire a Les Paul Junior - one of the most simple yet versatile wiring setups in an electric guitar.
That's pretty much it - it is time for final assembly - remove the harness from your template and put it back into the control cavity of your Les Paul Junior. The final step is to simply attach your pickups. As usual, the pickup ground goes to the back of the volume pot casing and the live goes to the input lug as per the wiring diagram. You will also need to ground the circuit to the bridge - this is achieved by running a ground wire from the back of the pot, through the body and to the bridge or tailpiece studs.
Guitar Wiring Guides