Pinch rollers are critical part of each cassette player. Together with capstan they are responsible for keeping correct tape speed. They are also responsible for keeping accurate position of tape in whole tape path.
When pinch roller is faulty or aged, it can have following consequences:
- it can curl (eat) some or all tapes
- it can cause speed variations
- it can cause azimuth instabilities
- playback can be randomly stopped
Some original pinch rollers are of very good quality. I have recorders from early 70’s, with pinch rollers in excellent quality. On the other hand, I’ve seen late 90’s machines with pinch rollers deteriorated.
Sometimes, pinch roller looks very bad, but after very careful cleaning, it can be again like new. When you get such cassette player, do one-time deep cleaning. I use cotton wool soaked in IPA, and clean it until surface is nice matte with uniform black color. If cleanup doesn’t help, then pinch roller needs to be replaced. Surface sanding is only very temporary solution and it is not recommended.
It is very important to clean pinch rollers regularly.
How do I know that pinch roller is bad?
1. Rubber is very hard
2. Rubber has cracks on the surface
3. Rubber is very soft
4. Rubber has poor adhesion properties. Try how you feel it with your finger. If it reminds you more plastic than rubber, then replace it
5. Surface is not smooth
6. Pinch roller core is fragile or cracked
7. Outer shape of roller is rounded too much…
Here are some examples
Rubber is hard and surface is glazed. When surface is glazed, you need to replace the pinch roller.
Rubber has cracks and pinch roller needs definitely to be replaced.
This pinch roller is good, after cleaning it looks and works like new. There is no need to replace it.
Surface is not smooth. This roller needs to be replaced.
Rubber has poor adhesin properties. It reminds plastic material, on touch.
This is new pinch roller, at first glance it looks good but it has three serious problems:
1. Rubber used is extremely hard. It looks like this roller was processed on lathe, instead of compression molding.
2. Outer surface is not rounded. Well, it is rounded, but backwards.
3. Hub seems to be made of sintered bronze, which is correct. However, after production, hole looks like post-processed by drill or reamer, i.e. hole surface is no more porous.
Avoid buying such rollers.