mac 512k won't boot from floppy

[mloret]

Hey guys,

A couple of weeks ago I posted a question about making a bootable floppy for my newly acquired Mac 512k. I managed to get disk copy on my Mac SE to create a serviceable copy of an OS 3.2 disk image on my floppy emu. Worked like a charm, no problem. Today I tried to boot and it didn't work. The issues vary but they are characterized by the happy Mac, but then it goes into a grinding noise when it says "Welcome To Macintosh" and I get a variety of errors and bombs. I just tried and it just kept trying to load but wouldn't get past the "Welcome to Macintosh" screen. I could hear that the drive was struggling mightily.

I tried another disk that I created and it didn't fare any better. The machine runs fine from the emu, so I'm thinking this is either a problem with the way I created the floppies OR the drive needs help. Which seems like a better starting point?

 

[mloret]

Oh yeah, I should mention that when I boot from the emu, it reads those same malfunctioning floppies fine. It just doesn't want to boot from them.

 

[mdeverhart]

When you boot from the Emu, you say that it reads the malfunctioning floppies fine. Have you tried copying anything to/from the malfunctioning disks when you’re booted from the Emu, or do you just mean that the disk shows up and you can open it and see the contents?

Has the drive been serviced at all? These old drives need to be cleaned and re-lubricated after all of these years. The heads may also need cleaning. You’ll want to service the drive if it hasn’t been done yet. @LaPorta has a great video on YouTube on how to do it on the 800k/1.4MB drives - I don’t know how similar the 400k drives are.

 

[LaPorta]

Which drive is it? The 400k is a totally different beast, and I haven’t had the chance to play with them as of yet!

 

[mloret]

Thank you for the response. I have serviced the drive and had it working but it randomly started doing what I described above. I plan on cracking the thing open again today to see what it does. I have used LaPorta's video with 800k drives and yeah, it's a different beast.

When I say that the disk works fine, I mean that it the floppy shows up as does its contents. I haven't tried to copy to/from the malfunctioning disks.

 

[LaPorta]

As a test, do you have a normally-working external 800k drive to test the disks on with this machine? I know you said the FloppyEmu works, but I wonder if the disks themselves are the issue.

 

[mloret]

Howdy. Yes I tested the disks on one of my 800k drives and both seemed to work. I'm a little perplexed why my 400k drive seems to read it when running from another disk but will not boot from the "bad" disks. Any idea? I hear what sounds like the stepper grinding...

 

[mloret]

and then the picture shakes sometimes and other things go awry. It's like it's not properly reading the disk, only parts of it. I suspect dirty heads or dirty stepper. Does that sound right to you?

 

[mloret]

Well, I found a neat article on here that detailed how to remove the carriage on the floppy. I had visions of an e-clip shooting across the room never to be seen again, but I actually was able to get the carriage off and I cleaned up the stepper which was disgusting. As of last night the computer booted from the floppy I created. I'll see what it decides to do today. Thank you for your help!