Help: Disk Drive Repair

[Dog Cow]

I cleaned the heads of 3 different SuperDrives (1.44MB, and all of that) and 1 IIgs 800k drive. Well, three of them, I managed to mess up. Here's how: I used a Q-tip to wipe some grime off the heads. The lower head was easy, since it's fixed. But since the upper head is on an arm, I lifted up the arm to get a better view when cleaning. Well, I guess I lifted the arm up too high, since now it won't snap down when a disk is inserted. If I use my thumb to press down the arm, the disk will read and boot OK, but that's not practical!

Any suggestions? It looks like maybe a spring or something got stretched out. I really hope this is fixable! 8-o

 

[superpantoufle]

Sadly no suggestion, but I too would be very interested in other's feedback on this topic. I recently manage to save one of my IIgs' 800K drives, but broke the other one in a similar manner than you. While trying to fix it, I disassembled and messed around with five of those drives, from the IIgs, a Mac Plus and a SE. Now I have two of them working fine, one completely blocked with a badly bent part in the eject mechanism, and two with a loose upper head, just as yours.

I'll folow this thread with greates interest, since I haven't got rid of those broken drives yet!

 

[Dog Cow]

The screws on the head arm are quite small, and so I shall have to purchase a miniature screw driver to remove the arm. Beneath it there appears to be a small spring, so I will likely need to make a trip to the hardware store to purchase a new spring for replacement. This spring appears to pull the arm down from below. OR, I could do something weird and glue a spring on top of the arm to press it down, such as is the case on a newer SuperDrive in the Quadra 605.

 

[Dog Cow]

Some intensive searching has revealed a few topics, but most are not so helpful. The mechanisms are actually Sony drives, as are most, so searching for the keyword Apple does NOT help.

Anyway, here's one topic:

http://techreport.com/forums/viewtopic.php?f=29&t=26001

I've managed to resurrect quite a few dead floppy drives by popping the lid off (they're so cheaply constructed these days that the lid usually just snaps into place rather than being screwed down), and gently cleaning both heads using a cotton swab dipped in 91% isopropyl alcohol. You'll need to lift the upper head arm slightly (it is spring-loaded), in order to reach the face of both heads.

Another:

http://www.howtofixcomputers.com/bb/ftopic59439.html

You might also take a cotton swab and pure alochol, cleaning

the heads gently AFTER blowing any excess dust out. If the

tension spring on the head arm seems to not be applying

enough pressure, and if it's the stepped-notch design for

the spring, adjust the spring to the next higher notch.

That's about all, if it still doesn't work then replace it.

It looks like I'm going to have to figure this out on my own. :-/

 

[tomlee59]

There is no adjustment, no pull-down spring that I recall. And don't unscrew anything; that will only make things much, much, much worse.

If you did not bend the copper-ish spring (it's not coiled; it's the flat piece that connects the head arm to the chassis) to the point of putting a crease in it, you have a chance of fixing it. But if there's a visible crease, your chances of resurrecting it go to approximately zero. You'll notice that the head's bottom travel limit is set by a plastic flange hitting a metal piece (or the other way around; I'm doing this from years-old memory, so there are bound to be errors). Temporarily lower that limit by gently bending the metal away, and then rebend the head arm to this new lower limit. Once you've accomplished that, bend the metal back to its original position. With care and luck, you should be able to get the head to load onto the disk surface properly.

 

[Dog Cow]

There is no adjustment, no pull-down spring that I recall.
If you did not bend the copper-ish spring <> With care and luck, you should be able to get the head to load onto the disk surface properly.

I did that before posting this topic, even putting a weight on the head overnight to keep it bent down. Helped a little bit, I think, but still wasn't enough. I haven't looked at the drives since last weekend, but I know what you are talking about with the copper piece. And I remember thinking to myself, "Is that the thing which pulls down the arm?!" I don't remember if I've creased it or not, so I'll have to take a look. But I'm almost certain I saw something which looked like a spring down below. I'll have to take a closer look.

Thank you for your advice.

 

[Scott Baret]

You're better off just replacing the drive. These internal floppy drives are still fairly common since many older Macs are parted out when they are combined with others.

If you need any drives let me know, I've got several spare 1.4MBs and a few 800Ks.

 

[Dog Cow]

Buying a new drive will be my last resort (thanks for the offer, though). The 800k drives are working now. It turns out that the heads were merely dirty, not bent.

However, there is definitely a tension spring which lurks below the head arm to keep it pulled down! It is hard to see, but when you shine a bright light, it can been seen attached down below. The next step is to obtain a small screwdriver so I can disassemble the head arm assembly further and see what to do about that spring.