06-25-2013, 09:42 AM
I posted this on the other forum but I want to also put it here to get as much exposure as possible.
This A.B. chassis has 4 bands; 3 SW and BC. It has a band switch shaft which has a round wheel on it (like a pulley);Y on picture. It connects to a small color wheel (X on picture) via a belt. When the band switch is rotated to a different band, it is supposed to turn the color wheel so the appropriate color shows up in a small window on the dial (Z on 2nd picture). For example, when the band switch is tuned to the "red" band (6-18 MHz), red is supposed to be displayed in the small window. As you can see in the picture of the dial, it is mostly red but some blue is showing. This is a good example; sometimes one color shows, sometimes two colors show, and sometimes they are completely "off" from the correct band because of slippage.
I believe originally there was a metal braided belt of some kind which controlled this wheel. However, it is now missing and I'm trying to figure out some way to replace it.
I have tried a rubber O ring, highly tensioned, but that has not proven to be successful. The lower band switch "pulley" is smooth brass and the color wheel is mounted on a hub which is also smooth metal. The O ring simply won't "grab" either so that it turns correctly. I have put some rosin solution on it trying to help its "grabbing power" but that was also futile.
I am wondering if any one has a suggestion what might be a possible solution. I have considered trying to super glue some sandpaper to the color wheel hub in order to gain some traction. But this is impossible to do on the lower (band switch) end of it because it is so narrow---just wide enough to accept a small diameter O ring. So it would continue to slip there even if the sandpaper idea worked on the top end.
Any ideas?
This A.B. chassis has 4 bands; 3 SW and BC. It has a band switch shaft which has a round wheel on it (like a pulley);Y on picture. It connects to a small color wheel (X on picture) via a belt. When the band switch is rotated to a different band, it is supposed to turn the color wheel so the appropriate color shows up in a small window on the dial (Z on 2nd picture). For example, when the band switch is tuned to the "red" band (6-18 MHz), red is supposed to be displayed in the small window. As you can see in the picture of the dial, it is mostly red but some blue is showing. This is a good example; sometimes one color shows, sometimes two colors show, and sometimes they are completely "off" from the correct band because of slippage.
I believe originally there was a metal braided belt of some kind which controlled this wheel. However, it is now missing and I'm trying to figure out some way to replace it.
I have tried a rubber O ring, highly tensioned, but that has not proven to be successful. The lower band switch "pulley" is smooth brass and the color wheel is mounted on a hub which is also smooth metal. The O ring simply won't "grab" either so that it turns correctly. I have put some rosin solution on it trying to help its "grabbing power" but that was also futile.
I am wondering if any one has a suggestion what might be a possible solution. I have considered trying to super glue some sandpaper to the color wheel hub in order to gain some traction. But this is impossible to do on the lower (band switch) end of it because it is so narrow---just wide enough to accept a small diameter O ring. So it would continue to slip there even if the sandpaper idea worked on the top end.
Any ideas?
