Sony TC640A Reel to Reel

[smartalec]

Recently acquired a Sony TC640A Reel to Reel.
Everything works well except stopping from rewind.
Supply reel (Right Hand One) keeps on turning dumping lots of excess tape before coming to a halt. Any suggestions very much appreciated.
Attached photo of brake mechanism.

[Kentode]

I've not worked on this deck but there is some adjustment on the brake spring in my picture. Try moving the spring up or down by one notch: it'll be better or worst!

[vidjoman]

Make sure the brake parts are free to move and also very clean and free of oil and grease.

[TIMTAPE]

Good advice already given. The proper test is the tension needed to overcome the braking. So a cord is wound around the hub of an empty reel, attached to a spring balance. The tension for one direction is higher than the other, and both reels should match in respective tensions.

[ms660]

What are the brake linings like, if they are worn you might have to adjust the brake lever to compensate.

Lawrence.

[ben]

This looks like a similar arrangement to the TC755A. Around the spool table lower drums there is a metal brake strap with a sort of sandpapery inner lining which disintegrates. You will have to renew this with something suitable. I used some industrial adhesive tape, not ideal but the best I have found so far. Some adhesive felt for protecting floors from furniture legs would be ideal but all that I found were too thick.

[smartalec]

Looks like i have managed to cure the tape dumping problem.
However i now have seem to have a horrible squeal coming from the brake drum on stopping,any suggestions appreciated,thanks to those who responded to my previous thread.

[ben]

Perhaps you would be so good as to tell us how it was solved, so that it would be of use to others in the same situation. Also, surely this post would be better off in the existing thread so we can follow the progress of the repair?

[AC/HL]

Threads merged

[vidjoman]

Originally Posted by smartalec

However i now have seem to have a horrible squeal coming from the brake drum on stopping,any suggestions appreciated.

Possible contaminated or hard brake pads.

[smartalec]

Originally Posted by ben

This looks like a similar arrangement to the TC755A. Around the spool table lower drums there is a metal brake strap with a sort of sandpapery inner lining which disintegrates. You will have to renew this with something suitable. I used some industrial adhesive tape, not ideal but the best I have found so far. Some adhesive felt for protecting floors from furniture legs would be ideal but all that I found were too thick.

I believe the Sony TC755A uses a brake band system,the TC640A uses a system very much like a brake shoe. Thanks anyway.

[smartalec]

Originally Posted by ben

Perhaps you would be so good as to tell us how it was solved, so that it would be of use to others in the same situation. Also, surely this post would be better off in the existing thread so we can follow the progress of the repair?

Problem was solved by bending the portion of the brake lever as shown in the service manual. Page 10 Brake Torque.