Rebuilding Mullen S12

Instruments, mechanical issues, copedents, techniques, etc.

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Bobby D. Jones
Posts: 3193
Joined: 17 May 2010 9:27 am
Location: West Virginia, USA

Rebuilding Mullen S12

Post by Bobby D. Jones »

I started rebuilding a Mullen S12 Jan. 1, 2026.
The first part went well. I cleaned/lubed pedal bar, Pedal rods. Removed the key head, Nut roller assembly, Cleaned and polished. Polished rollers.
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Bobby D. Jones
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Joined: 17 May 2010 9:27 am
Location: West Virginia, USA

Re: Rebuilding Mullen S12

Post by Bobby D. Jones »

Today I started on under carriage. The pull rods are a disaster. I am thinking about making new rods. Less work than cleaning these rods.
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Bobby D. Jones
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Joined: 17 May 2010 9:27 am
Location: West Virginia, USA

Re: Rebuilding Mullen S12

Post by Bobby D. Jones »

I removed the rods and found that the cross rods are bad too. The guitar has been around the ocean or store with some chemicals.
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Dean Smith
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Location: DFW, Texas, USA

Re: Rebuilding Mullen S12

Post by Dean Smith »

Looking good, Bobby....Following.
Patrick "Dean" Smith
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Larry Jamieson
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Joined: 30 Jan 2001 1:01 am
Location: Walton, NY USA

Re: Rebuilding Mullen S12

Post by Larry Jamieson »

Looking good so far. I'm curious... Is peanut butter a good cleaner or is it a lubricant? I'll keep track or your progress.
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Jerry Overstreet
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Location: Louisville Ky

Re: Rebuilding Mullen S12

Post by Jerry Overstreet »

Your guitar, but those pull rods are just fine the way they are. They will operate as intended. I've owned several Mullen guitars and some of the pull rods all looked similar. I suppose it's the material oxidation on them and the cross shafts but it doesn't hurt a thing.

That said, if you want to replace them they will look better though.
Last edited by Jerry Overstreet on 6 Jan 2026 8:54 pm, edited 1 time in total.
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Dennis Detweiler
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Re: Rebuilding Mullen S12

Post by Dennis Detweiler »

Rub the metal parts with 400 wet/dry under the faucet to get the bulk off. I'm thinking, get a bench mount buffer and some buffing compound. You should be able to make the metal parts shine. Rub with oil for preservative.
1976 Birdseye U-12 MSA with Telonics 427 pickup, 1975 Birdseye U-12 MSA with Telonics X-12 pickup, Revelation preamp, Ibanez Analog Mini Delay and Hall Of Fame Reverb, Crown XLS 1002, 2- 15" Eminence Wheelhouse speakers, ShoBud Pedal, Effects Pedals. 1949 Epiphone D-8.
Bobby D. Jones
Posts: 3193
Joined: 17 May 2010 9:27 am
Location: West Virginia, USA

Re: Rebuilding Mullen S12

Post by Bobby D. Jones »

This guitar came from near the Atlantic Ocean. I wonder if salty sea mist caused this problem.

I worked on the cross rods today, I used a wheel of steel wool with a plastic binder, It took the weird crud off.
The cross shafts, Pull rods, Little plates that the pull rod hooks into, Pedal stop brackets and changer bar stop plate are Cadmium plated. The cadmium and chemical reaction is the problem.
I think shinney stainless steel pull rods would give the under carriage a classier look.
Bobby D. Jones
Posts: 3193
Joined: 17 May 2010 9:27 am
Location: West Virginia, USA

Re: Rebuilding Mullen S12

Post by Bobby D. Jones »

Removed neck and changer. Removed all parts from underneath, Except 1 bar, It has the pickup wire run through a hole. Will clean it in place.
Removed all parts from cross shafts and cleaned them.
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When removing bell cranks or other parts from the hex shafts. (Remove set screw), Place wrench close to the parts base, Wiggle wrench parallel with the cross shaft to unseat and remove the part.
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Cleaning up the cadmium plated parts that are corroded. The changer stop plate needs its slots polished, For smooth changer movement.
Picked up enough 1/8" Stainless steel rod to make new rods for guitar.
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Sam Inglis
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Location: United Kingdom

Re: Rebuilding Mullen S12

Post by Sam Inglis »

Do you need to take precautions when cleaning cadmium plated items? The use of cadmium even in small quantities is pretty much outlawed in Europe owing to its toxicity.