Progress update. Nearly complete. If you have a C22, MX110, C11, MA230 or MA5100 with loose and/or scarred rocker covers, this solution may interest you.
I originally planned to make this repair given the loose, sloppy feel of the rocker buttons and rotted foam. I took the opportunity to install new rocker covers as the old ones were scarred with scratches and fingernail indentions. You could just as easily keep your original rocker covers if you are happy with them.
Tools used:
- Oscillating multi-tool with metal cutting blade (e.g. Dremel MM40-05 Multi-Max).
- Scissors or exacto knife
- Shop vac
Parts:
- K&S Precision Metals #9820 2mm brass tube
- New McIntosh C22 reissue rocker covers #07159700
- Pemko Camper Tape PEM-P480 (mylar backed closed cell vinyl sponge tape, waterproof)
- 99% isopropyl alcohol
- Cotton swabs
- Rubber Cement
Steps:
- Use an oscillating multi-tool to drill through the solid rivets, which have hollow crimped ends.
- Vacuum metal debris
- Use 99% isopropyl alcohol to remove glue and foam from the slider switches (and old rocker covers if you reuse them)
- Cut foam to size and adhere with rubber cement (or a superior adhesive) to back of rocker covers
- Cut 2mm brass tube to size. You will need to cut four pieces total because the potentiometers make it impossible to thread two long pieces of tubing. Instead you need one medium and one short length of tubing per side -- totaling four pieces.
- Install new rocker covers and insert 2mm brass tubing
- Crimp ends of brass tubes
Below: multi-tool cutting rivets to extract the old rocker covers
Below: The elusive slider switches finally revealed.
Below: Vacuuming debris
Below: The old tired, scarred rocker covers
Below: New C22 rocker cover sitting on top of extracted 1960s MX110 rocker cover for comparison. New cover appears to be virtually identical to vintage.
Below: testing the fit of K&S 2mm brass tube through the pivot hole of brand new rocker cover.
Below: Experimenting with the Pemko P480 camper tape using an old rocker cover in order to match the old glue marks for sizing. This tape has an adhesive side which faces the back of the rocker cover. In addition, the tape has a mylar protective coating which faces the slider switch. I discovered that adhesive on the Pemko facing the rocker cover will need to be supplemented. I'm thinking rubber cement may work but I haven't yet tested it. You can tell from the yellow gunk on the old rocker covers that McIntosh also had to use some type of extra glue material to lock down the foam.
Below: clean debris off of the slider switches.
Below: Confirming the brand new C22 rocker cover will fit with the 2mm K&S brass tube. The new rocker cover is fresh and unscarred by decades of fingernail indentions!
Next steps: I need to find a suitable adhesive to bind foam and plastic. Would rubber cement be best?
After I have the new foam firmly secured, I will install the new covers, crimp the tubing and button it back up.