Pinch Roller Cleaning

[BassHead]

I got a new mini box in the mail and of course issues with the cassette deck. Near the end of a quick maintenance run through, I started to clean the pinch roller. After about 30 q-tips (both sides), the black stuff wasn't getting any lighter. I tried a little fine sand paper to see if that would help, and it got more gunk off. Then I went back to cleaning with Q-tips and went through another 20. The dirt on the q-tip doesn't seem to be getting any lighter, making me wonder will this ever end?

I will admit the sound is getting much better. Should I keep cleaning until there is no more black gunk coming off the roller?! Just wondering if this is normal as this seems like a sh*t load of q-tips. About an hour into cleaning the roller and not even finished!

Thanks

Mike

 

[toshik]

I use cotton swabs with rubbing alcohol preferably 99% I don't go wild - just a few swabs so the main dust comes off don't go wild not to over dry pinch roller.

 

[Fatdog]

Mike, are you using something other than isopropyl alcohol? It almost sounds like you are using a solvent-based cleaner, which could be eating the rubber.

 

[Jorge]

Dude, it sounds like you have to buy a new pinchroller! Hope u'r using Naphta, not something else for this fit of mastur$&@...!!!!!
My 2cents of personal pain: I spent hours restoring a pinchroller for a "mini-me" for RC-550 (posted here, somewhere) only to realize that I do have to shell $20 for the new rubber ;-(

 

[BoomboxLover48]

Use my technique to make a new one.....

https://boomboxery.com/forum/index.php/topic/25320-how-to-refinish-pinch-rollers/?hl=%2Bhow+%2Bmake+%2Bpinch+%2Broller

Don't waste money to buy pinch rollers for $75.

 

[BassHead]

I've been using Isopropyl 91%. I own Rubber Renue (Rubber rejuvenator) but have also read a lot of bad things about the chemical and that it shouldn't be used on pinch rollers.

I do think the pinch roller on the 550 is toast. Also the motor had a dead spot...and now it's now gone kaput.

My pinch roller on my new JVC 525 cleaned off nicely with Isopropyl..about 5 swaps and light residue. Also the pinch roller spins is MUCH stronger....further indication the pinch roller could be the source of some of the issues I've had with the 550.

With my 525, the spindle plays strong. When I put in a cassette, it seems to struggle. It will play slow for a few minutes, then speed up, then slown down. Not slow W&F but extreme. It really looks like the spindle can't handle the torque. It seems very strange as the mechanism appears strong when there is no tape in the deck. Belts are brand new. Any clue what it could be? I think the motor could ALSO have a dead spot (Damn JVCs). Could that be the issue...worn motor...not able to provide the necessary torque?

Thank You.

 

[Jorge]

A new motor from Pacific Stereo should fix 550, or I can send you (my treat) restored original RC-550 motor (resto photos at square-2.com). I am going to buy a new pinchroller from Mihokm for my "mini-me 550" RC-414 (its just $20, about the same price as this whole "mini"... but I put so much efforts into its resto that it has to be finished nicely!) and shall report how it went. What you describe is exactly what I am dealing with now: worn capstan brass sleeve and totally ruined pinchroller. W&F over the roof, tape gets pulled side-wise and wrinkled, the whole nine yards!
BoomboxLover48 has a real awesome tip here, wish such know-hows were "pinned" somehow. While waiting for Mihokm pinchroller I will try this!

 

[BassHead]

I opened up the 525. This model uses a square drive belt (SBS10.7). Using tweezers, I removed the belt off the motor pulley and the motor plays very strong but every so often it's a little sticky but when slightly moved it starts spinning strong again (I don't think it's a dead spot in the motor...it looks like a lack of lubrication issue). Then when I put the belt back on the motor pulley...the motor struggles. The belt doesn't appear to be too tight. I'm going to buy some of the Naphtha product you recommend and clean all the rollers. I'm on vacation (w/ my 525) and don't have my lubricant and other supplies, so I will wait until I get back on Thursday.

Let me know how the pinch roller replacement goes. I will be looking at doing this to the 550. The pinch roller is shot on the 550. As you had mentioned on square-2, there is flat pin on either side and may take some creativity to replace. I'll look for BoomboxLover's recommendation.

Man you are awesome. If you really would offer....I'd throw you shipping cost for that 550 motor . Plus I would send you the "dead" motor currently installed as I'm sure you could do something with it.


What are the main areas of the deck that you need to keep greased? The spindles? What type of grease? Knowing this would help...and I think the 525 might be needing some grease...somewhere, just not sure where.

 

[Jorge]

will ship RC550 motor on Monday-Tuesday, not a problem! RubberRenu should work, Naphta is just something a real Pro recommended to me once. Sold for a few bucks at hardware stores, among lacquer and paint thinners.
yours sound like a classic "dead spot", but once up and running it should pull the mechanism. Dont be shy, with belt off try rotating the flywheel with your finger with Play or FF engaged. If there is something askew you should feel it.
Re oils, there is a whole list of recommendations at tapeheads forum, mine included 5W30 motor oil from the nearest gas station is the one i still have to get into my collection
Capstan seems to get the hardest hit: eccentric pull from both pinchroller and flywheel can result in this horror:

(from my poor RC-414), rotating it 60 degrees clockwise is the only "fix" I could think of, but unfortunately for RC550 this is not possible because of the mounting screws/hardware

 

[BassHead]

Jorge...you are great! I got back from my trip to Massachusetts, to the package at my door. I spent the night sleeping at the DC airport because of bad weather/cancelled flight, so I wasn't in the best mood once finally getting home (34 hours after leaving MA). Haven't opened it, but know what is inside. Thank you so much. Need to get some sleep first, but will be opening the RC550 up this weekend to have a look and map out a plan. I'll be in touch.

As I previously mentioned, I took my solder class, and will be ordering a solder set. Actually met a DIY electronics group in the process, so it will be fun to pick their brains. I also want to swap the leads to the mid-speaker as you suggest!

 

[Jorge]

Hope the motor will fix the problem, Good luck!!! I did not see any hardened grease on mine (and it was in a pretty bad/neglected shape!) but as I mentioned before, just check with your fingers that everything else moves smootly. Now you can follow my photos and open your dead motor to clean and lube. Or send it my way, maybe someone else will need it. I put a new Elna SilmicII cap in yours, just because I had it. But Rubycon 105C rated cap should be better.
Re new pinchroller: in this JVC the pin should be drilled out, unfortunately... I will post photos once get a new pinchroller from Marian Mihokm
Hope to see your report of resurrected 550 soon
Cant wait to see if you like its sound with mid driver flipped!

 

[BassHead]

Jorge....these are a couple photos that might help explain some of the text from my PM. It looks like the pinch roller is near impossible to remove...but I cant imagine JVC designing it this way considering this is a wear part.

 

[Jorge]

Unfortunately Yes, thats how JVC designed it... I had to drill out the pin. If you stop just when it is free to go, you may be able to reuse it.

 

[BassHead]

Hi All. Hi Jorge (sent you a PM).

Been away because of personnel issues, but will be back trolling again!

While I had been away a new pinch roller from overseas made its to my house, and by bending the assembly and removing the rock hard old roller, I was able to get it on! Now I have a new roller on the 550 pinch assembly. See attached photos. Behind this assembly was a spring, shown in the 3rd photo. What is it used for? It seems like it still would engage without it. Secondly does anyone have a photo to help me install it correctly or provide some verbal instruction?!?

This is it...and then I'm putting her together. This will be the first box that I replaced all belts, replaced motor, replaced pinch roller, as well as several cosmetic items. I'm excited to see what happens when I hit play. Its been a great learning experience nonetheless.

 

[baddboybill]

The spring is needed to keep tension on pinch roller against capstan shaft so yes it does need to go back in same way.