By: Mike Bennett
BRC/Thorn Tuner Repair
The main problem is the plastic parts that lock each tuner button when pushed
Regarding those collars, you can use normal washers but, unless you use enormous ones, the springs tend to ride up over the washers and start uncoiling themselves or getting tangled up with the latch mechanism. All you need are some M6 cup washers for use with 19″ rack equipment and some M6 “penny” washers. These can be obtained all over the place, but here’s as good a place as any.
Anyway, below are some instructions on how to fix those pesky Thorn tuners.
To fix the tuner:
- 1 – Remove the four screws holding the tuner latching mechanics to the tuner itself.
- 2 – Remove the tuning bar spring and separate the two sections. Put the tuner section to one
- 3 – Remove the customer knobs and put them to one side.
- 4 – Release the latching bar by straightening the two tabs and pulling the latch bar forward.
- 5 – Remove the latching bar and spring and put both to one side.
- 6 – Undo the four Phillips screws INSIDE the square-section push-bars. These can be very tight so the correct size screwdriver and a pair of pliers can be useful. Put the screws to one side.
- 7 – Turn the spindles in a clockwise direction (as viewed from the customer-end) and remove the square-section bars.
- 8 – Remove the four rear-most circlips (nearest the customer) that stop the spindles from returning too far and put them to one side.
- 9 – Now the spindles can be slid back enough towards the customer end to remove the spring.
- 10 – Remove the remains of the plastic collars from the square-section bars and throw them away.
- 11 – Remove the springs.Slide on to the spindle the metal M6 “penny” washers so that they touch the circlip at the end of the spindle thread.
- 12 – Take the springs and push each one into the cups of the plastic M6 “cup” washers and then push both back onto the spindle so the back of the “cup” washer touches the “penny” washer.
- 13 – Slide the square-section bars (slotted end towards the spindle) through the square holes and onto the spindles taking care to make sure the spring doesn’t get trapped or tangled.
- 14 – Screw the spindles anti-clockwise (as viewed from the customer side) a dozen-or-so turns to join the square-section bars to the spindles.
- 15 – Replace the rear-most circlips onto the spindles taking care to make sure the rubber and thin plastic washers are on the customer-side.
- 16 – Screw the four Phillips screws back into the end of the square-section bars. Make sure they’re reasonably tight.
- 17 – Check the action of the spindles and springs – make sure the square-section bars don’t come out of the slots when the spindles are turned fully anti-clockwise. The bars should be flush with the “chassis” – If they can be turned too far back then an extra “penny” washer is
- 18 – Replace the latching bar by pushing it through the slots and bending the tabs very slightly and re-attaching the spring.
- 19 – Check the action of the latching bar on each spindle.
- 20 – Replace the customer tuning knobs.21 – Re-attach the tuner and tuning bar spring to the mechanism.
- 22 – Test the action of the unit as a whole.
- 23 – And that’s it. You’re done.