Repair your Magnus Chord Organ:
Now that you have disassembled your organ, it may be necessary to repair it. Listed are the most common problems and the proper course of action to repair them. We will then give you a few tips and reassemble the unit on Page 3.
Buzzing Notes
Buzzing notes are caused when the reed contacts its channel. See the first reed? Notice how it scrubs the channel on the left? This is easily repairable with a utility razor blade. Find where the point of contact is and shave the channel and/or reed as little as possible around it's perimeter to fix the problem.
Silent Notes
Silent notes are usually caused by a stiff or stuck reed. If the reed is stuck, free it and trim around its perimeter to prevent sticking again. If you can not blow on reed or flick it on the tip with your fingernail to produce a very quiet tune, then it has become stiff. Clean it with rubbing alcohol and use a small screwdriver to work it back into proper vibration. BE CAREFUL not to move it too much or too far, it might break. If note plays, but is very quiet or wimpy sounding, this is caused by an air leak that we will address how to repair in a few moments.
Sticking Keys
The keywork of the organ is very primitive. The keys are one piece, numbered for orientation, and have a rocker shaft that passes thru them and the holder. To remove the shaft, remove the E-Clip that holds it into the metal frame and remove the shaft. This is MUCH easier said than done, the shaft is about a 9/10 in difficulty to get out but easy to put back in. You can NOT use WD-40 or any sort of chemical in this step as it will damage the keys.
Once the shaft is removed, sand it smooth and now you may give it a light coat in WD-40 and let it dry completely. Clean the keys (Dawn and water) dry. But DO NOT submerse the keys.
Use a Q-Tip to clean the spring buckets out. Note the rusty rocker shaft, this is from sitting outside or haven gotten wet at some point. Half of the time you will find further rust in the case or a sticky spot from where something was spilled in the organ years ago. Also note it is common to find broken chunks of case and dead bugs... yummy!
Tuning Notes
Unfortunately a Magnus Chord Organ can not be tuned. The organ is just a giant harmonica with buttons. People have debated shaving of the reeds and adjusting their heights but it has limited success. The two octave models are usually fairly in tune with themselves, and even other instruments. The three octave models from the late 70s are fairly decent, however the older models high octave is usually quite poor, and even lower octaves are not in tune with other chord organs. Magnus moved the fan further in and forward and got a higher-powered unit that will force the correct amount of air thru the upper reeds and make them speak properly on the latter models.
Air Leaks
Since the Magnus Organ is so primitive, there are a few things we can do to prevent air leaks, which is the number one cause of improper playing. Step one is easy, and involves simple 3/4" masking tape. Since the rubber seal shown below is all that keeps air from seeping out of the duct, and we don't want to glue the duct in for future repair, run a few pieces of tape (two layers thick) around the perimeter of the board with the seal still in place. If your seal is not 100% intact, you will need to replace it with foam weather stripping 1/8" thick or something similar you have laying in the garage.
Seal attached to duct:
Taping perimeter of board to duct:
No more air leaks!!!
You need to do this same procedure around the auxiliary (chord) boards and to the outer edge of the duct where it fits into the case. Use a pencil to mark and poke holes where the screws went and tighten them up. Not too tight, remember this is plastic (or bakelite): snug will do it. This same procedure can be done to the vent holes where the keys fit if the seal grate is torn or damaged, but usually it is fine. Also, some people have fit felt or rubber pads to the bottom of the keys where it covers the air vent. I have not tried this but believe it would work but may quieten the organ if the seal was too thick, (more than 1/8"). However, this could be a good thing as some are LOUD!
Now that you've fixed your organ, it's time to put it back together on Page 3