cracked disc tray on scsi cdrom drive

[Nathan]

I recently obtained a replacement used SCSI cdrom drive for my Power Mac 6100/66. The previous drive (original I think) had a problem with not ejecting the tray (made motor noises but no eject). Unfortunately in the process of using the newer one (which does work at least) I discovered that it's disc tray has a  crack down the center (horizontal, parallel to case front). It's not quite broken, but still...

Is there a solution for this besides hoping for the best and/or stealing a tray from a different drive? Could it be glued? Any chance I could swap out the tray from the other drive (assuming that one's not damaged in some other way)?

old:   AppleCD 300i Plus CR-503

new: AppleCD 12X         CR-507-C

 

[FacnyFreddy]

I used to take short lengths of Trylene fishing line then swab 2-part clear epoxy (Elmers brand) over it carfully and I got moving parts like trays and such to function again.

 

[Alex]

I had a drive that would not eject. I fixed it by adding a thin piece of tape between the magnet and the other piece that the magnet goes over. It  appears that the motor weakens over time but the magnet remains strong therefore it doesn't eject. I am not sure about the crack but I would use glue designed for plastic to prevent it from separating completely.

 

[butterburger]

Belts go bad (weak, stretch, loose), in optical drives as young as even five years. A modern optical drive's disability to open tray, is usually due to worn/aged belt, not due to weak motor. Geared trays are noisier than belted trays, but can go decades without ageing/decaying. However, gears are more likely to break than belts.

 

[Alex]

Belts go bad (weak, stretch, loose), in optical drives as young as even five years. A modern optical drive's disability to open tray, is usually due to worn/aged belt, not due to weak motor. Geared trays are noisier than belted trays, but can go decades without ageing/decaying. However, gears are more likely to break than belts.

Some good points but in my case I had to go with a similar solution. 

In my case, as in the case of the instructions in the video, it's about reducing the strength of the magnet. By reducing the magnetic strength the motor that spins to pull away from the magnet succeeds with disengaging otherwise the tray doesn't open.

Hope this helps.

 

[butterburger]

Alex, your method does help. I had done something similar, rather than buy a replacement belt: I opened drive (removed case top) and stuck ordinary sticky tape directly onto spindle. Your solution is much cleaner: you put the spacer into counter-spindle disc pad (or whatever to call it), where it cannot erode. I did not know how to do that! I thought that shiny metal circle part of top case was welded, or somehow otherwise permanently affixed; I did not try to pry it off. Thank you for sharing.

I would like to clarify one thing from my earlier reply: a gear is more likely to break than a belt, if used heavily (such high duty role might be high volume disc duplication, or integrity checking). Usually, the gear which breaks is the one which is smallest, and spins at highest speed. A geared tray open/close mechanism can seem to last forever, if used sparingly. After much time, belts can break, even if never used.

 

[Alex]

I wonder if the belts should be lubricated to keep them from drying and cracking. Perhaps my assumption is wrong. Does anyone know a source for the belt? Lube might work but may cause slipping, not sure.

In terms of gears, I might suggest a total take apart and inspection and an eventual clean up of the gears and fresh lubricant. I've done this and it should help as it clears the tracks, avoiding added pressure. The old lube may become hardened if dried out, or even sticky, becoming a dust and dirt collector. This might help prevent damage and allow longer life.

Finally, its fun to take stuff apart, learning as you go and eventually reconditioning things.