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Apparently Possessed 400k Floppy Drive
Posted by: khannonnd on 2016-01-25 16:07:32
So I fired up my original Mac for the first time in about a month, and the floppy drive seems to have been possessed by a demon in the interim.  

The drive will read/boot from a disk no problem, but it makes an unholy sound whenever it reads or writes to the disk.  See attached movie.  It sounds louder than it does in the movie.

Is this as simple as the head needs to be lubricated or is this a sign that the drive is dying?

Thanks!

IMG_0681.MOV

Posted by: Gorgonops on 2016-01-25 16:13:20
Uhm... I dunno, it sounds like the drive in my 512k pretty much. Unless it's a *lot* louder in real life I think that's what they sound like?

Posted by: khannonnd on 2016-01-25 16:18:14
Uhm... I dunno, it sounds like the drive in my 512k pretty much. Unless it's a *lot* louder in real life I think that's what they sound like?
I guess what I can say with 100% certainty is that when I first got and had the drive installed 6 weeks ago, it was almost silent.  At least I seem to remember it being relatively silent...  Maybe I am just misremembering?

(and yes, I know that the latter half of this post gives lie to the beginning half which states I was 100% certain =p)

Posted by: khannonnd on 2016-01-25 16:32:12
Never mind, I must be crazy.  I YouTubed some videos of original Mac's in action, including the great videos from Jason (like this one: 

) and I guess the 400k drives are just generally loud compared to other drives.  Oh well.Sorry for the useless thread!

Posted by: Gorgonops on 2016-01-25 17:39:32
They do have that weird singsong warbling that makes you wonder, don't they?

Posted by: Elfen on 2016-01-25 17:43:41
Sounds normal to me. The 400K Drives speed up and slow down depending on what track they are on on the floppy disk.

If it worries you, you should take the drive out and with a q-tip and acetone, remove all the old lubrication from the rail and stepper screw the head is on and swab it down with some fresh White Lithium Grease.

Posted by: Gorgonops on 2016-01-26 09:37:53
 The 400K Drives speed up and slow down depending on what track they are on on the floppy disk.
So do the 800K drives (and Superdrives when they're reading 400/800k disks), but for whatever reason they don't sing the way the 400k's do. The one thing that is different is that all the later drives ignore the PWM signal from the Mac and control drive speed themselves depending on what track they're on instead of the Mac reading the Tach signal and tuning it in itself. Vaguely have to wonder if the speed control circuitry built into those later drives works more efficiently and some of the singing is due to the Mac having to "hunt" the correct speed a little more crudely on the 400k.

Posted by: techknight on 2016-01-26 14:35:04
this is normal for this day and age, However, re-greasing the spindle bearings will definitely quite it down some. 

Posted by: falen5 on 2016-01-27 15:43:34
all of mine sound like that. Those old drives used different speeds to rotate the disk didnt they -

Worst sound i ever heard from a mac floppy drive was from an 800k drive i got that was seized. The bearing on the motor/spindle for turning the disk had rusted and would not rotate -so i soaked it in wd40 - gave it a day - still would not turn

so i made the mistake of forcing the motor to spin(thumb on the spindle on the back of the drive). It freed up pretty easy after some crunching of rust sounds , that soon went away. after a minute or 2 it was rotating freely

-

so i plugged it in. as soon as i popped in a disk.....my god....the noise..........

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long story short....i must of cracked the bearing, or damaged a bush ...something... i dont know......but the spindle was loose(very slight sideways movement). When the drive tried to rotate a disk this very very small amount of play gave rise to some kind of resonance / harmonic motion that just screamed - it was terrible. The drive would only sometimes read.

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it is now in the spares bin.

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so if your drive's motor has siezed.....do not force it to rotate...it will kill the drive. I rekon i should of taken it fully apart and just soak  it in wd40 for a week or 2

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