My trusty Toshiba SCSI CDROM drive recently started spitting out any
disc it was asked to load after 3-4 seconds.

Took it apart and found the plastic tray drive gear had cracked - small
one, on the motor spindle, ~5mm diameter. It's a press-fit on the
spindle, and apparently still had enough grip to open and close the
tray, but let go when the additional load of lifting the laser head sled
into place was applied.

I went looking for super glue, but it was all dried up as usual - even
the one in the fridge. I've been known to tackle the odd plumbing job,
so when I found a bottle of "PVC to ABS transition solvent cement", I
couldn't resist trying it.

I opened one end of the cracked gear about 0.5mm with a razor blade,
poked cement into the crack with a needle, squeezed it between two
fingers for a couple of minutes, then cleaned off excess cement with the
needle.

The repaired gear was a tight fit on the spindle, but did not crack
again. CDROM now works perfectly :-)

Sunny