Help converting a VCR into a tape cleaning machine

[Henenen]

I've seen this German guy on YouTube who's stripped down an old VCR and made a rather charming Heath Robinson tape cleaning machine, to quickly remove loose mould from old VHS tapes.

https://www.youtube.com/watch?v=gG4Jt-VxMpg

I really want to make something similar, but have very little knowledge in how to do it myself, would some kind souls please help me?

I've already got an old Matsui donor VCR. I've taken the head drum out. The cassette still inserts and is taken up OK when I press play, but then is immediately retracted back into the cassette and the machine shuts off.

I'm guessing there's some sort of sensor dictating this behaviour? Is there something that checks for tension against the head? Or isn't there some sort of light sensor in VCRs that shut them down if certain conditions aren't met (to avoid tape damage, etc...)

Here's my machine with the tape taken up:
http://oi45.tinypic.com/x5poc3.jpg

[Maarten]

The drum motor needs to be connected to provide servo feedback. It's not clear from the picture whether it is.

[Rick62008]

The link you provided for the photo isn't working for me.
If your VCR has a normal DC motor just disconnect it from the VCR and plug it to 5 to 12 volts.
Also it would be better to disassemble the tape and run the tape reels directly on the VCR deck. The cassette's housing and the tape reels themselves should also be cleaned.

I need to do this myself one day, I just haven't got a junk VCR yet for it :P

If anyone has better suggestions please shoot, I would like to improve this cheapo technique as well

[ben]

All that device is in the video is an old Funai deck with the load arms screwed in position and the motor hard wired to a 12v supply. I once made something similar. The older the deck the better, the new ones are too flimsy!

[Henenen]

Originally Posted by Rick62008

The link you provided for the photo isn't working for me.
If your VCR has a normal DC motor just disconnect it from the VCR and plug it to 5 to 12 volts.
Also it would be better to disassemble the tape and run the tape reels directly on the VCR deck. The cassette's housing and the tape reels themselves should also be cleaned.

Here's photo link again: http://oi45.tinypic.com/x5poc3.jpg

Why would it be better to run the reels outside of the cassette? Just so the cassette & spools can be cleaned?

TBH I was gonna clean the spools too, but just put them in a non-infected cassette, of which I have 100s!

If I just connect the motor to a 12V supply, how do I make it go at different speeds, is it be increasing/decreasing the voltage? Also, how would I make it rewind?

[ben]

Spools are better outside the cassette so that dirt falls off.
To alter the speed somewhat, you can vary the supply voltage I suppose. You don't necessarily need to alter speeds or make it rewind, just put it back in the cassette when it has passed from spool to spool, cleaned.

[Henenen]

Originally Posted by ben

Spools are better outside the cassette so that dirt falls off.
To alter the speed somewhat, you can vary the supply voltage I suppose. You don't necessarily need to alter speeds or make it rewind, just put it back in the cassette when it has passed from spool to spool, cleaned.

I don't really want the dirt to 'fall off'!

It's microscopic mould spores, ideally they'll be caught on the wet cloth. If they become airborne I risk infecting all my other tapes.

I'd like to be able to vary the speed so I can slow it if needed and check/watch the mould is coming off and how it's coming off. I've seen some guys o YouTube just put a mouldy tape in a normal VCR, FF it through and 'hey presto, the mould is gone!' Except it hasn't, it's now scattered all around their machine.

[Rick62008]

Originally Posted by Henenen

If they become airborne I risk infecting all my other tapes.

It would be best to do it in a open space, even for health reasons although i guess that black mold should be the most dangerous of all, but also rare.

Yesterday i have tried to clean a moldy tape with the help of a old tape rewinder and a spare empty cassette shell and cassette reels.




And a closer look:


I opened the original cassette, removed the tape reels, disconnected the tape from one of the reels and connected it to a cleaned tape reel and then placed it inside of a clean empty cassette shell. After half of the tape was winded and cleaned i removed the spare cassette from the tape rewinder, cleaned everything possible inside and replaced the cloths with new ones and continued with the winding\cleaning until the tape reached the end. Then i replaced the other original reel with a spare clean reel to rewind the tape again and repeated the same steps (until half-way of rewinding replaced the cloths and cleaned everything inside the space cassette shell).
While tape was winding i cleaned has best as i could the original tape reels and original cassette shell. Maybe reusing the original shell and tape reels wouldn't be at all advisable but i wanted to give it a go and see how it went.

I did winded and rewinded it in my balcony so i couldn't care less about airborne mold.

I guess you can never clean a moldy tape at 100% and i know this isn't a perfect technique, but still this worked for me.

As for variable voltage why don't you try something like this?
http://alexcentro.gr/images/detailed...ptor-mw701.png

It's cheap and easy to use.

[Henenen]

Ah yes, tape rewinders - I'd forgotten about those!

Where I live however, people are literally throwing VCRs out day by day so I've no shortage of junk decks to get my hands on.

I've stripped the main tape playing mechanism out of the deck:
http://oi48.tinypic.com/2daj9k8.jpg

This is the motor:
http://oi47.tinypic.com/2vjew0n.jpg

Do I just snip the red and white wires away and connect the positive and negative wires from a 12V supply?

Someone said earlier it had to be a DC motor - how can I tell if it is?

Yes, I also plan to do this outside, or round a friends house who doesn't have and VHS tapes any more.

[ben]

The motor in the second pic looks like the load motor, not the spool drive. Can you post a pic of the deck underside?

[Rick62008]

Seems like there will be an driver IC for the capstain\reel motor. Either you get the schematic for it and get it going or that VCR was a bad pick for that specific project :P

[Henenen]

Here's the underside:

http://oi50.tinypic.com/v2vfx0.jpg

What's a Driver IC?

[Rick62008]

The driver IC is that integrated circuit (black part) near that big wheel with a belt which is a three phase flat motor (if i'm wrong someone please correct me on this). In order to make it run you would need to get a datasheet for that integrated circuit but if you don't have much experience with this kind of electronics than it could be a bit tricky.

You're better off checking another junk vcr and pick one with a motor and two wires going in much like the load motor on your deck or even like the one in the video you showed in your first post.

Another ideia would be this.

https://www.youtube.com/watch?v=A4V028IIt9s

I might build one of these myself!

[ben]

Rick's right.
Ideally you need a video from the 80s, like a Hitachi VT11, or an Amstrad vcr4000 or 6000 which (I vaguely recall) use a straightforward DC brush motor for spooling.

[Henenen]

Would the service manual have the datashet for that integrated circuit?

I've seen lots of downloads for the service manual of this VCR model (it's a Matsui), but they're all paid for.

Are there any free databases/websites of service manuals?

[ben]

If I were you I would not waste time with that Matsui. You'll have a hard, time-consuming and possibly expensive job to make the necessary driver and power requirements for that motor.

I have just dug out and photographed one of the mechanisms I was talking about. As you can see from the underside pic, it uses a single large DC sankyo motor to drive the spools (reverse polarity for rewind!) and capstan. There is another little one for the mode cam and eject/cass basket. The drum motor has its own DD brushless one. All motors can be used independently of each other

That deck was used in roughly 1988-1990 vintage Funai, Amstrad (Note: pic attached - found online), Fidelity, Roadstar, Philco, Shinko, Aiwa VCRs.

[Maarten]

Ah yes, that nice-and-awful-at-the-same-time Funai deck. One of the first really 'bendy' decks on the market, and it went downhill from there. When (not if) the dumper rubber went soft, it was an easy fix to just bend the piece of metal it was once mounted on and not fit a new rubber. The (by then quite obsolete) separate DC-motor is a definite plus.

[ben]

Once you changed the belt kit (they didn't use to last long!), and attended to that rubber stopper, they were actually quite reliable. However, occasionally there'd be one with a duff mode switch (symptom: poor unlacing, pic search mode not working motor not shutting off) which wouldn't respond to cleaning, they were a PITA as considerable disassembly was needed to gain access.

[Henenen]

OK, will take your word for it on the IC!

The chances of me finding an older machine for free are much much slimmer. I might try wrapping the heads of an old machine in cotton wool in the meantime, like this guy:
https://www.youtube.com/watch?v=UFsXZDd4K-8#t=3m37s