Card reader head cleaning

[Dave Britten]

What's the conventional wisdom on keeping mag card reader heads clean? I know there were some special purpose "cleaner" cards provided back in the day, but what's available now that's safe to use? Can I just snip a piece of an index card to roughly match the size of a mag card, and feed it through a couple of times? Maybe give it a very light coating of 99% isopropyl alcohol first?

[Raymond Del Tondo]

Hi,

if you can find an index card of the thickness of the mag cards, it should work.
Thicker cards may lead to kinda paper jam.

I'm not sure whether isopropyl alc. could damage the transport wheel or not.
If the transport wheel has been replaced, it could work w/o damage,
but if the card reader wasn't serviced so far,
I suspect the alc. damaging the old transport wheel.

[teenix]

(12-30-2019 03:46 AM)Dave Britten Wrote:  What's the conventional wisdom on keeping mag card reader heads clean? I know there were some special purpose "cleaner" cards provided back in the day, but what's available now that's safe to use? Can I just snip a piece of an index card to roughly match the size of a mag card, and feed it through a couple of times? Maybe give it a very light coating of 99% isopropyl alcohol first?

Pushing "something" in may damage the rubber drive wheel. The head itself is more accessible from the exit side of the calculator.

You could also open the calculator and clean the head and any other dust and "stuff" that might be in there. I have used IPA in the past. Acetone is probably a bad idea as it may damage plastics.

I'm not sure I would use abrasive tape cleaning products anymore. Some of the heads I've seen are quite worn already.

cheers

Tony

[Dave Britten]

(12-30-2019 04:38 AM)teenix Wrote:  

(12-30-2019 03:46 AM)Dave Britten Wrote:  What's the conventional wisdom on keeping mag card reader heads clean? I know there were some special purpose "cleaner" cards provided back in the day, but what's available now that's safe to use? Can I just snip a piece of an index card to roughly match the size of a mag card, and feed it through a couple of times? Maybe give it a very light coating of 99% isopropyl alcohol first?

Pushing "something" in may damage the rubber drive wheel. The head itself is more accessible from the exit side of the calculator.

You could also open the calculator and clean the head and any other dust and "stuff" that might be in there. I have used IPA in the past. Acetone is probably a bad idea as it may damage plastics.

I'm not sure I would use abrasive tape cleaning products anymore. Some of the heads I've seen are quite worn already.

cheers

Tony

Ah, so it would be better to stick a little cleaning strip in from the left side instead?

I made a little "unprotect" card for my 65 so I can rewrite application pack cards that have degraded magnetically, and when inserting it from the left, I can feel a small increase in friction/resistance at about 1.5 inches in, and then it's blocked completely at 1.75 inches (I'm assuming it's hitting the drive wheel). Is that quarter inch of increased friction where the heads are located?

[teenix]

(12-30-2019 04:51 PM)Dave Britten Wrote:  Ah, so it would be better to stick a little cleaning strip in from the left side instead?

I made a little "unprotect" card for my 65 so I can rewrite application pack cards that have degraded magnetically, and when inserting it from the left, I can feel a small increase in friction/resistance at about 1.5 inches in, and then it's blocked completely at 1.75 inches (I'm assuming it's hitting the drive wheel). Is that quarter inch of increased friction where the heads are located?

That's correct. The slight friction is the head, then you hit the drive wheel. The ball switches are further in which you won't get to from this side unless you force the card through the drive wheel.

cheers

Tony

[Dave Britten]

(12-30-2019 10:09 PM)teenix Wrote:  

(12-30-2019 04:51 PM)Dave Britten Wrote:  Ah, so it would be better to stick a little cleaning strip in from the left side instead?

I made a little "unprotect" card for my 65 so I can rewrite application pack cards that have degraded magnetically, and when inserting it from the left, I can feel a small increase in friction/resistance at about 1.5 inches in, and then it's blocked completely at 1.75 inches (I'm assuming it's hitting the drive wheel). Is that quarter inch of increased friction where the heads are located?

That's correct. The slight friction is the head, then you hit the drive wheel. The ball switches are further in which you won't get to from this side unless you force the card through the drive wheel.

cheers

Tony

Okay, and the heads themselves would be on the bottom, right? i.e. the cards have data written on the back. I wouldn't use anything more abrasive than paper to clean the heads, with maybe a tiny drop of alcohol applied on the cleaning side, then just give it a couple of swipes in and out the left side of the slot. Does that sounds like a safe way to do it?

So far the card reader is working fine, I'm just planning ahead in case the heads get any oxide buildup.

[teenix]

(12-30-2019 11:14 PM)Dave Britten Wrote:  Okay, and the heads themselves would be on the bottom, right? i.e. the cards have data written on the back. I wouldn't use anything more abrasive than paper to clean the heads, with maybe a tiny drop of alcohol applied on the cleaning side, then just give it a couple of swipes in and out the left side of the slot. Does that sounds like a safe way to do it?

So far the card reader is working fine, I'm just planning ahead in case the heads get any oxide buildup.

Cleaning solution on same side as magnetic surface of card - facing downwards.
Sounds ok

Years ago when I worked for the telephone company we used to have to clean relay contacts with thin strips about the same size as the magnetic cards. These had a micro brush surface on both sides which would be ideal for this purpose.

cheers

Tony