I have an HP 3055 all-in-one. I've been refilling the genuine HP 2612a
toner cartridge that came with it. I've refilled it 4 times. During
the last refill, I also drilled the waste chamber and emptied it (it was
making a black streak down the middle of the pages printed). Now it has
developed a black mark down the extreme left margin. It is about 8 mm
(5/16") wide, looks like a railroad track, and runs from the top part of
the page to the bottom. I thought it might be due to some waste toner
still stuck in the end of the waste chamber, but I have tapped the
plastic in that area and it has made no difference.

Also, the cartridge prints a little faint.

I want to see how many refills I can get out of it before it dissolves
in a pile of dust. I give the money I save to charity. Any suggestions
as to how to fix the RR tracks and the faintness?

By the way, the holes I am using are:
To fill: 30 mm (1-1/4") to left of and 30 mm (1-1/4") below the left
hand tip of the lifting handle.
To empty: 37 mm (1-1/2") to right of and 37 mm (1-1/2") above the right
hand tip of the lifting handle.
(These descriptions are based upon the cartridge sitting so that the
label area is above the handle.)

Thanks

Henry