01/27/2025
Allen & Heath SQ Fader Repair / Replacement
Step by step how-to instructions - NOT ENDORSED by Allen & Heath - use at your own risk! This should be performed by qualified individuals only!
Note this is also how you replace failed faders (in this unit there was one, plus we broke one intentionally trying to modify). Note that replacement faders may have the same gummed up grease issue as well depending on their vintage and if the brass roller doesn't move freely should be cleaned and lubricated prior to installation.
On mobile the captions don't always appear so here they are:
1 - Identify the bad/slow faders by marking the front of the unit with painters tape and indicating the bad ones. Remove the fader caps from all faders by prying gently straight up with a small screwdriver. Use an index card against the chassis to avoid scratching.
2 - Flip the unit over on a soft surface, remove all screws indicated to release the lower rear cover. Caution fans on the cover are attached, so open slowly.
3 - Unplug left fan.
4 - Unplug right fan behind header connector
5 - Unplug fader board power connector by depressing tab and removing. Remove all fader connections (yellow). Remove screws indicated by arrows.
6 - Unplug fader board control header connector by sliding the release levers away from the center (green). Remove all fader connections (yellow). Remove screws indicated by arrows
7 - Unplugged. Number faders with sharpie if you plan to return them to the same slots.
8 - Unplugged. Number faders with sharpie if you plan to return them to the same slots.
9 - Faders exposed. Each fader is held in with two screws from the front of the unit. Remove as needed for work.
10 - Common issue location is the brass roller grease has gummed up and the wheel does not roll
11 - Video showing brass roller gum up issue
12 - Video showing how to clean the roller. Remove the belt first and pull out of the way with clean gloves. Use a solvent to dissolve the existing grease until the roller spins and falls freely. Spray one final time. Be careful not to get any spray on anything but the metal parts, the spray will destroy the belt and fader traces.
MG Chemicals 413B Flux Remover works well to clean grease from wheel. Horace Whitlocks Clock Oil works great to re-lubricate the wheel once cleaned (ensure solvent has completely dried first, typically place faders standing upright in parts box overnight).
13 - Video showing clean and dry brass roller moving freely. Reassemble belt on pully. Oil with small needle drops from Horace Whitlocks Clock oil. Test fader to ensure the wheel spins freely when fader is moved.
Reassemble unit in reverse order.
