Hohner SG Lion RepairThere seem to be a construction error in the tremolo system on all Hohner Professional SG Lion models. |
The construction error is that the rightmost metal, pointed out by the red arrow, is too weak to withstand many years of pressure from the two blue springs.
You can see that the edge is no longer completely straight.
The red V illustrates how far the base of the springs have been pulled out of position.
The problem is to force the base of the springs back to its original position.
The idea for this repair is insert a bolt inside the guitar, and then pull the springs back.
A bolt with a big round head is modified (1) to fit between the springs (2) and get a firm grip of the spring base.
The tremolo system is mounted after repair.
The bolt that pulls the springs back can be adjusted from below the microphone.
Since no tools I could find allowed me to drill horisontally inside a 70mm by 70mm hole, I had to invent the tool myself.
A flat 8mm drill was cut in two (1) and the edges of the drill head was changed (2) to fit into an angeled bit holder (3) for a normal electric screwdriver.
With the newly made drillhead it is now possible to make a perfect hole inside the guitar, from the room under the tremolo system to the room under the microphone.
I messured out that the hole must have its center 21mm below the upper edge for the type of bolt I had at hand.
The microphone space is not as deep as under the tremolo system, so the bolt enters directly over the surface.
To make space for the nut you will have to remove a few millimeter of wood.
Check that the nut can turn before mounting anything.
Modify a piece of metal to reinforce the narrow wall of wood, before tightening the nut.
There is less space for the microhpone after repair because of the reinforcement plate.
Check that your microphone can be mounted with the plate in place before assembling anything
You need to be able to hold the bolt in an upright position while tightening.
The bolt must be modified so you can hold it with one hand, while turning the nut with the other hand.
An adjustable spanner will fit the modified end of the bolt and the open spanner on the next picture fits the nut.