PS2 drive grinds and pops out disc

Hi, I recently attempted an installation of the Flip Top cover on a v4 Playstation 2 [fat]. As I'm on this part of the forums, I've obviously encountered an error during the installation. I seemed to have done something to my disc drive accidentally. I'll try and post pictures later, so I'll be as descriptive as possible for now.

Problem [happens both with and without the Flip Top cover on] - Whenever I start up the PS2 and open up the drive (whether I place the disc in through the Flip Top or opening the drive), I place a disc in, ready for the game to boot up (or SwapMagic). However, when the drive slots in or when I start up the disc, the PS2 drive begins to spin (or really, just attempt to). The problem is that the disc that is in the drive doesn't stay in the drive holder. The disc begins to make a slight grinding noise against the drive holder's surface and usually will come out (kind of like pop out) of the disc holder. I have no idea how this happened as the installation went fairly smoothly. I'm a bit scared to try and test discs to see the problem as I don't have any blanks at the moment, thus risking some of my PS2 games to scratches from the grinding.

And just making sure, I did take the white magnet holder from my original PS2 disc top "case" and put it into the new Flip Top.

If anyone has a solution to this problem, I'm all ears. If I didn't describe the problem well enough, I'll try to get pictures up as soon as possible (or even a video link).

I appreciate anyone's help. Thanks <3.

Sounds like either one of two problems.

1. The magnet is not grabbing onto the disc very well, or at all.
a. Could be caused by making the fliptop lid too high so the magnet doesn't clamp onto the disc and grinds on the top of the disc and or bottom of the white magnet holder.
b. Perhaps the magnet, or metal piece is not in the white plastic thing anymore?
2. The rubber on the spindle is worn and not grabbing the bottom of the disc very well.
a. Check that it is clean, if not clean with rubbing alcohol.