Date   : Mon, 17 Aug 2009 20:26:46 +0100
From   : rs423@... (Mick Champion)
Subject: Floppy drive cleaner

Sorry Rick, I sent this to you vice list. Arrrgh!


Rick Murray wrote:


>   
> >Ribbed paper can not be considered safe IMO.
> That's why I said the REVERSE (flat) side of the paper.
Oh dear. I never read anything right first time. Sorry about
that.<embarrassed>


>  I think ribbed 
> envelopes are a heavier grade of paper.
I see.



>  Apply when the head is spun up 
> (3000rpm) with PRACTICALLY NO PRESSURE AT ALL. 
>   
Best to move the head drum by hand rather than power it up to be
honest.  It's 1500-1800rpm by the way (25-30 frames per second). I think
you have doubled your speed calculation based on 50 fields per second
whereas each field is read on opposite heads on the drum so 1 rotation
1 frame(2 fields). 25 frames per sec x 60 seconds = 1500 rpm. Well I
think this is correct?

> Move ONLY in the 
> direction of the spin, if at all. NEVER up and down!
I agree with you about never wiping up and down. Don't move in a way
that a tape wouldn't do itself.




>  A useful rule of thumb if your deck isn't overloaded with 
> electronics is to hit pause and see how 'noisy' it is.
>   
That is not such a good guide to be honest. As you know, regardless of
how many heads are on the video drum, only 2 video heads are used. Which
two depends on the mode ie.SP/LP/EP. Each head reads half a frame (1
field), and is switched in and out alternately. When on pause it is
likely that only one field / head is being read. So if one out of the
two heads is very dirty, when on pause you could either see nothing but
white noise, or a perfect picture (that's if your VCR did beautiful
pauses in the first place) whereas a single dirty head on playback would
appear to be the picture with white noise flashing in and out. What I
mean is a perfect pause, don't mean the heads are clean, just the one
being used for the pause.




> Oh, and don't forget that applying pressure of any sort to the spinning 
> drum will alter its speed so the picture freaking out like that is 
> normal. :-)
>   
I personally would not clean the heads with a tape inside, but I know
you have had success with your method, so who am I to knock it. :-)



>   
>> I'll use chamois leather every time.
>>     
>
> Try finding a suitable one. I found one in the supermarket and it had a 
> texture like felt. I can imagine if I put that anywhere near the drum, 
> it'd rip the heads off!
>   
When you say felt, do you mean soft or abrasive?. If you've got any auto
shops similar to Halfords over the Channel,  have a look for some there.
It should be soft / non abrasive and porous. If abrasive then really?,
and has as it still got any wool still attached ? ;-)   Don't forget to
also clean the erase and ACE(audio control erase) heads,  plus guides
and capstan.


>
>   
>> Last time I attempted clean a disc drive (5.25"), I must have applied 
>> too much pressure. One of the two heads promptly fell off :-( Treat
>>     
>  > them gently folks.
>
> I think the glue or whatever that holds heads in place can 'age'. Looks 
> like some sort of epoxy resin? I had one drive fall apart when I put it 
> on the desk (and I didn't throw it!). Thankfully there were little guide 
> holes in a sort of ribbon circuit that had the head mounted in it, so I 
> could glue the thing back together and, better yet, it worked!
>   
Wow, that's a great result. Did / does it read your old discs or only
write read new ones? I thought it was incredibly hard to get the heads
aligned properly. I wish I hadn't dumped my old drive now, but seeing as
it only read one side after I mangled it.....




> Treat old drives GENTLY, period!
>   
Yes boss ;-)



Take care,


Mick