Doctor B.
02-15-2008, 12:54 PM
I knew from day one that my new 29 year old CT-F1000 would need a set of pinch rollers. The old ones were hard and shiny. Cleaning and sandpapering only made them smaller and didn’t significantly increase the traction especially on the take-up side. The spring for that roller was at maximum tension and the roller was at the top of its range of travel when the transport was engaged. On thin tapes, it was slipping. Disaster struck when a rare tape that I found at the GW for 50¢ got mangled as I was cleaning it hoping to get it to stop slipping in the tape player.
Searching for pinch rollers for the CT-F1000, I found that they are made of “unobtainium.” The Pioneer parts web site showed them as no longer available. There is an AK member who rebuilds rollers and I imagine he does good work, but that would cost me $75.00 for the set of two.
I found that MCM sells pinch rollers (www.mcminone.com - no association), but the closest size they have is 10x6x1.5mm. The CT takes 10x6mm rollers, but the pinch roller shaft is thicker than 1.5mm. I figured that for 83¢ apiece I could figure something out. One option was to try drilling out the nylon hub so that it would fit the shaft on the pinch roller assembly. If I had a good drill press with a fine set of blocks for small work, that would have been the first thing I would have tried.
I noticed that the original pinch rollers are fixed to a brass ring and a brass hub is pressed into the center of the ring. The original brass hub is slightly larger than the nylon hub in the new pinch rollers from MCM. (Please pardon me for not giving exact measurements - no micrometer at hand.) Using a vice, it was easy work to press out the brass hubs from the old rollers and then to slip them into the new rollers. Because the brass hubs are slightly larger than the nylon ones, I am not too worried about the rubber moving out of place when the rollers are operating under pressure. Perhaps a drop of superglue would make them more secure, but I didn’t try that.
When I reassembled the left pinch roller assembly, I found that the slight increase in the new roller’s size made it rub against the plastic tape guide. Removing the tape guide and placing two strips of paper under it and screwing it back to the assembly gave enough clearance around the roller and it could move freely.
I put everything back together and put in a test tape to align the azmuth. The test tones sound pretty solid to my ears. I don’t know how to make precise measurements for wow and flutter (though I am interested in learning). For the moment, I like what I am hearing and the deck is playing tapes consistently well. I am keeping my eye on the rollers to see whether they “creep” on the hubs. If so, I’ll try a drop of glue. So far, they are staying in place. Time will tell whether this is a good permanent fix. I’ll post my results after a few months of use.
$1.66 plus shipping is my kind of repair. :music:
The attached pics show 1) left: original CT-F1000 pinch roller, right: 42-3255 pinch roller from MCM, 2) left: original roller with the hub pushed part of the way out, right: roller with no hub, 3) left: original roller with no hub, center: new roller with nylon hub removed, right: new roller with original brass hub installed.
If anyone has the Additional Service Manual for the CT-F1000, I sure would appreciate a scanned copy. I'd like to make sure the playback equalizer and flat amp are adjusted correctly. I don't plan to record, just listen.
Searching for pinch rollers for the CT-F1000, I found that they are made of “unobtainium.” The Pioneer parts web site showed them as no longer available. There is an AK member who rebuilds rollers and I imagine he does good work, but that would cost me $75.00 for the set of two.
I found that MCM sells pinch rollers (www.mcminone.com - no association), but the closest size they have is 10x6x1.5mm. The CT takes 10x6mm rollers, but the pinch roller shaft is thicker than 1.5mm. I figured that for 83¢ apiece I could figure something out. One option was to try drilling out the nylon hub so that it would fit the shaft on the pinch roller assembly. If I had a good drill press with a fine set of blocks for small work, that would have been the first thing I would have tried.
I noticed that the original pinch rollers are fixed to a brass ring and a brass hub is pressed into the center of the ring. The original brass hub is slightly larger than the nylon hub in the new pinch rollers from MCM. (Please pardon me for not giving exact measurements - no micrometer at hand.) Using a vice, it was easy work to press out the brass hubs from the old rollers and then to slip them into the new rollers. Because the brass hubs are slightly larger than the nylon ones, I am not too worried about the rubber moving out of place when the rollers are operating under pressure. Perhaps a drop of superglue would make them more secure, but I didn’t try that.
When I reassembled the left pinch roller assembly, I found that the slight increase in the new roller’s size made it rub against the plastic tape guide. Removing the tape guide and placing two strips of paper under it and screwing it back to the assembly gave enough clearance around the roller and it could move freely.
I put everything back together and put in a test tape to align the azmuth. The test tones sound pretty solid to my ears. I don’t know how to make precise measurements for wow and flutter (though I am interested in learning). For the moment, I like what I am hearing and the deck is playing tapes consistently well. I am keeping my eye on the rollers to see whether they “creep” on the hubs. If so, I’ll try a drop of glue. So far, they are staying in place. Time will tell whether this is a good permanent fix. I’ll post my results after a few months of use.
$1.66 plus shipping is my kind of repair. :music:
The attached pics show 1) left: original CT-F1000 pinch roller, right: 42-3255 pinch roller from MCM, 2) left: original roller with the hub pushed part of the way out, right: roller with no hub, 3) left: original roller with no hub, center: new roller with nylon hub removed, right: new roller with original brass hub installed.
If anyone has the Additional Service Manual for the CT-F1000, I sure would appreciate a scanned copy. I'd like to make sure the playback equalizer and flat amp are adjusted correctly. I don't plan to record, just listen.