Wiring⁢ maintenance⁣ on Gibson semi-hollow guitars is often viewed as a daunting task by many guitar technicians. I remember my first attempt at fixing teh wiring on my vintage ES-330 years ago;​ it took me an hour just⁣ to extract the⁢ harness and nearly two weeks to reinstall it!

Some liken this process to the ⁤challenge ⁤of fitting a ​ship⁣ inside a bottle. However,wiht the right techniques and tips,you’ll find that wiring can be more ⁤manageable than you might ⁣expect.

guitar Overview

Today, we’re focusing on a Gibson ES-335 from the late 2000s, which has been experiencing issues​ with scratchy potentiometers⁤ and tone controls that⁣ only⁤ seem to work when nearly turned off.

James, ‌the owner of this guitar, decided it was⁣ time for an upgrade. He opted for a new wiring harness featuring⁤ Armstrong Music’s Premium 450 Series 550k potentiometers and Luxe Radio’s ⁤Sprague​ Black Beauty replica capacitors.

Disassembling the Guitar

To begin the harness removal, you’ll need to take off the strings, tailpiece, bridge, and pickguard. If you can’t measure the action beforehand,use masking tape to secure the bridge-post thumbwheels in place.

Removing the control knobs can be tricky,⁢ especially if they’re tightly fitted onto the pot shafts. While there ‌are specialized ⁢tools for this, I frequently⁣ enough‍ use two teaspoons to gently pry ⁤them off. Just​ be sure to place thick cardboard⁤ or ‍cork between the spoons and the guitar body to avoid damaging the finish.

Next, unscrew the nuts securing the⁣ potentiometers⁣ and output jack, along with the switch ring nut. The harness should drop into the body, but first, ⁢you’ll‍ need to disconnect the ground wire,‌ typically soldered to​ the bridge pickup’s lead wire. Remove the four screws from the pickup ring, lift out the pickup, and you’ll find the ⁣connection.

Be⁤ cautious as the‌ wire can be stiff ‌and wrapped around the pickup ⁢wire. Carefully unwrap it while melting the solder. It’s wise to cover the guitar to protect the finish from any solder drips.

Harness ‌Removal Techniques

Check the bridge pickup cavity to see if you can extract the harness⁤ through the pickup⁤ hole.In this case, there was‌ a generous gap through the center block, but some⁤ semi-hollow guitars‌ may only have a narrow‌ opening for the pickup ​wire, necessitating removal through the ⁣treble-side f-hole.

Using​ my fingers and a ‍wooden dowel, I guided the switch toward the pickup ⁣cavity, which also pulled out the ‍neck-pickup ⁢control pots, followed by the jack socket and‌ bridge-pickup pots. If you encounter tangles with the pickup wires, take a step back and gently maneuver them instead of forcing anything.

Soldering the New Harness

Wiring ‌guitars like Teles,Strats,SGs,and Les Pauls is relatively straightforward since you can attach switches and pots to the body or pickguard⁢ before​ soldering.Though, with​ Gibson thinlines and most hollow-body​ guitars,⁣ proper spacing of ⁣components is crucial for a⁣ smooth installation.

To achieve this, I created a template. I ‍placed a sheet of A4 paper over the body ⁢holes and pressed⁤ down to make‌ indentations. This simple‍ method accurately marks the control layout positions, which I then highlighted with‌ a ‌pencil.

Next, I placed the paper over a piece of MDF and used ‍a spike to transfer the layout by poking through the⁤ pencil marks.‌ After⁤ drilling ⁤holes in the ‌MDF,⁤ I could mount the socket, ⁢potentiometers, and switch before assembling the new ⁣wiring harness. For the jack socket⁣ and pots, a 9.5mm or 10mm bit is needed, and a 14mm bit or step cutter for the switch.

While MDF is not the⁤ best material due to its softness, I plan to⁤ use Perspex next time. Since the harness is assembled from the underside, marking each template ‍hole on both sides⁢ helps avoid confusion.

Assembling the Harness

Although the potentiometers James provided were rated at 550k, the actual⁤ values often differ. You can measure the true ​value‍ by checking the resistance across the⁢ outer solder tags.In my experience, vintage 500k pots frequently‌ read higher, sometimes closer to 600k.

If you want to‌ reduce muddiness from a neck pickup, use the pot with the highest actual value in‌ that ⁢position. Conversely, ⁢opt​ for the⁤ lowest value‍ pot for the⁢ bridge volume if it sounds overly radiant.⁤ In this case, three pots measured between 515k and 519k, while one was 529k.

With ⁣the switch, jack socket, and all pots secured to the template, ​it was time⁣ to assemble the‌ harness. While it’s possible ​to install the harness‌ through the bridge-pickup cavity, I prefer the‍ f-hole method, having ‍learned a few tricks⁤ over the years.

Installation Tips

One key tip is to solder⁣ the braided wires to the sides of the pot casings instead of the backs. ⁤I discovered this technique while reassembling a harness from a 1964 ES-335.

Getting the potentiometers through⁢ an f-hole requires a twisting‍ motion, and there’s limited wiggle room.When the braided wires are soldered‌ to the back, it can create a tighter fit, but attaching them to the‌ sides⁢ makes them almost invisible.

Another helpful ‌trick is to lengthen ⁤the wires connecting the neck tone control to the jack socket and ⁢between the neck‍ and bridge⁣ pickup controls. This allows for a ⁢more‌ staged​ installation rather than trying⁢ to ‌fit everything​ in at‍ onc. ⁢Some techs use ​string or twine to pull components into position,⁢ but I’ve found that surgical tubing often leads to tangles.

Rather,I start by ⁤securing the jack socket while keeping the other ​components outside the body. I thread some braided cable‌ through ⁤the socket hole and ‍pull it out through the f-hole.⁢ After placing a star washer over the wire, I push it ‌through the socket and ​tie ⁢a knot.

With the star washer ‍and socket inside the body, I pull them into position ⁤using the braided wire. Maintaining tension, I run⁣ a washer ‌and nut⁢ down the wire⁣ and tighten everything up. ⁢As long as there’s enough wire accessible at ⁢the ⁢f-hole, phase one is complete.

Before connecting the neck⁣ pickup controls, the‌ pickup wire must be threaded through the f-hole and soldered to ‍the volume pot. I ensure there’s ⁣adequate protection between ⁣the ‍pot and the finish ⁢while making the solder joints. After ⁢that, the switch and neck⁢ pickup controls can also be inserted through the f-hole.

Once inside, I ‌secure star washers to prevent twisting. You⁤ can use your fingers to⁣ maneuver the switch into position before tightening⁤ it with its ring nut. The volume pot ​can ⁢be adjusted similarly, but the tone ⁣pot is often harder to reach.

When the harness is assembled on a template, you can be confident ‍that the pot shaft will align with the hole. I use a⁣ dowel to guide ⁤the pot until the shaft⁤ is visible,‍ then grab it with long tweezers to pull it ‌through.

From​ there,it’s straightforward: solder the bridge pickup to the volume pot and push the⁤ pots through the f-hole. Both pots will be⁣ easily accessible, allowing ⁢you to ‌lever them up ‍through⁢ the holes to complete the installation.

Final Steps

The extra wire length in the⁤ harness is roughly equivalent to a couple of pedalboard patch ⁤cables, which doesn’t concern me. This⁣ added length not only simplifies the ‍harness installation but also allows for individual removal of ‌volume pots for cleaning or pickup swaps without needing to take out ‍the entire harness.

Even though I only tackle this job about once a year, I’m no longer intimidated by it. Nowadays, I can complete it in about 45 ⁤minutes rather of two⁤ weeks. So, give it a ⁢try!