Mac Plus "Sad Mac" problem

[Phipli]

Does anyone know if the Mac LC III floppy drive is the same 800k drive as the one in the Plus? Or is it a 1.44mb or something? I don't know much about floppies. It looks like a very healthy drive so I was wondering if I could swap it once I have the Plus.

The LC III came fitted with two different floppy drives, the manual inject and auto inject. They changed the case between them. If your LC III has a smooth face it has the later manual inject, if it has a single groove across the front it has the older manual inject. Both drives are a 1.44MB drive.

The older style drive will probably fit the Plus and even work as an 800k drive I believe, but... I'd probably try and find an 800k drive for it if I had to. But, drives are usually repairable, so I'd expect to repair rather than replace, assuming the drive isn't missing. Especially as any replacement is just as likely to need work.

The newer style drives aren't ideal for older machines. The slot is at the right height and you can't easily push the disk in far enough for the drive to accept it (where they're fitted stock, the later drive openings have "lips" so you can push your finger in - the older drives don't have the lips and the drive itself takes the disk off you, hence auto-inject).

 

[PowerPCFan]

The LC III came fitted with two different floppy drives, the manual inject and auto inject. They changed the case between them. If your LC III has a smooth face it has the later manual inject, if it has a single groove across the front it has the older manual inject. Both drives are a 1.44MB drive.

The older style drive will probably fit the Plus and even work as an 800k drive I believe, but... I'd probably try and find an 800k drive for it if I had to. But, drives are usually repairable, so I'd expect to repair rather than replace, assuming the drive isn't missing. Especially as any replacement is just as likely to need work.

The newer style drives aren't ideal for older machines. The slot is at the right height and you can't easily push the disk in far enough for the drive to accept it (where they're fitted stock, the later drive openings have "lips" so you can push your finger in - the older drives don't have the lips and the drive itself takes the disk off you, hence auto-inject).

Alright makes sense. I actually don't have the case, board, HDD, etc., for the LC III - just the floppy drive and power supply. Do the manual and auto inject ones look different on the inside?

 

[Phipli]

Alright makes sense. I actually don't have the case, board, HDD, etc., for the LC III - just the floppy drive and power supply. Do the manual and auto inject ones look different on the inside?

Do you have a photo?

 

[PowerPCFan]

Do you have a photo?

I'm actually not at home right now but later today I can take off the cover of the LC III drive and send a photo. I think mine was from around September 1993 if that helps.

 

[LaPorta]

This looks like a very nice project. Two suggestions on top of all the very good ones above:

If you want a set of adjusting sticks:

Amazon.com

Something like that is cheap and will work on all kinds of adjustments.

Second, it isn’t hard at all to fully disassemble the floppy drive when it is time, if you are so inclined. My video shows how easy it can be to remove the Mylar discs:

 

[Phipli]

Second, it isn’t hard at all to fully disassemble the floppy drive when it is time, if you are so inclined. My video shows how easy it can be to remove the Mylar discs

Yes.... I didn't say it wasn't do-able. It is just mylar is brittle and if one does fail it would be tricky to get a replacement Mylar washer with an interference fit to post on a 35 year old floppy drive... given that not removing the still results in a perfectly serviceable drive, I just don't bother taking the risk. It isn't a difficulty issue, its a consequence issue.

One of my overhauled drives working perfectly without having had the second layer removed :

 

[LaPorta]

Yes.... I didn't say it wasn't do-able. It is just mylar is brittle and if one does fail it would be tricky to get a replacement Mylar washer with an interference fit to post on a 35 year old floppy drive... given that not removing the still results in a perfectly serviceable drive, I just don't bother taking the risk. It isn't a difficulty issue, its a consequence issue.

One of my overhauled drives working perfectly without having had the second layer removed :

Absolutely. Most times I don’t bother (and, frankly, with a Plus that doesn’t have a fan, I never have). For that LCIII with fan, there could be a significant dust collection under there. All depends on operating conditions: I’m sure that you, too, have seen from totally pristine drives to ones that you’d think a cat coughed a hairball into!

All depends on how far our friend @PowerPCFan wants to go.

 

[Phipli]

I’m sure that you, too, have seen from totally pristine drives to ones that you’d think a cat coughed a hairball into!

Its always nice to work on a drive from a machine without a fan. My external drive looked new inside!

 

[PowerPCFan]

What's the battery for on the back of the Plus? Looks like an energizer battery from the 80s or 90s but i don't think it leaked

I ordered a torx screwdriver for the handle, it should arrive soon

Edit: it chimes, but shows that zigzag line pattern

 

[LaPorta]

The battery is for holding the PRAM settings and time for the clock. Not strictly necessary for the operation of these machines at all. They do sell equivalents on Amazon and the like if you want it. I keep my working machines with their batteries, though many do not.

 

[dochilli]

If it chimes, then the ROM may be ok.
Did you turn the brightness knob (under the apple logo)?

 

[PowerPCFan]

If it chimes, then the ROM may be ok.
Did you turn the brightness knob (under the apple logo)?

No, but the screen is extremely bright so I doubt that's a problem

 

[PowerPCFan]

also, is the mouse connector supposed to be missing a pin in the corner?

 

[s_pupp]

All my working mice for the Mac Plus are missing a pin, including the mouse that came with the Mac Plus I bought new in 1986.

To add to the complications of replacing the floppy drive in a plus is that you have to match the floppy cable (yellow stripe vs red stripe) to the floppy drive (red label vs black label - the BMOW website has some details regarding this. If mismatched, you can end up with a floppy drive stuck in eject mode - the eject motor runs continuously until the power is switched off.

 

[bibilit]

The Analog Board is provided with another potentiometer for brightness, you can always try to get it down once the casing has been removed.