PrinterTechs swing plate assembly upgrade
So why the heck does this gear wear out anyway? There are several factors but in general the gears just aren't meshing as well as they should. There is too much movement between the fuser gear and the swing plate gear and the plastic gear isn't durable enough to take the stress.
There isn't much you can do about this. HP improved the swing plate assembly by adding a spacer disc (see below) which helps limit some movement in the gear but it's sort of a Band-Aid fix in my opinion. If you really want to fix it, buy the metal swing plate gear!
The second problem with the plastic gear is the metal pin wearing out the hole in the center of the gear. This problem is especially noticeable with the cheap aftermarket gears most companies are selling. The metal pin wears down the plastic and the diameter of the hole becomes larger. This speeds up the teeth wear because now the teeth aren't meshing correctly.
Another improvement worth mentioning is the metal reinforced locking clip. In the 42x0 43x0 printers two blue locking clips lock the fuser into place. The original clips had a tendency to break on the gear-end of the fuser as shown below, but the upgraded metal reinforced clips keep the fuser in place. Now just because the fuser is locked in place doesn't mean it stays perfectly still. The fuser wiggles and shimmies around a bit which probably contributes to the stress on the gears.
There isn't much you can do do stop the stresses that cause the plastic gear to wear out, but you certainly can beef up the gear. And beef it up we did! We tested our metal gear past a million pages worth of wear.
We tested the gear through normal printing conditions as well as a specialized test setup shown below. By adding an external motor to the main gear drive we cranked the RPM's up on the main gear assembly to the equivalent of 110 pages per minute, over twice as fast as the printer's rated speed.
BTW, this was also a great way to test the durability of our fuser fixing films. They performed incredibly well!. If you buy one of our maintenance kits with a remanufactured fuser you can rest assured the durability of our components are top notch! In fact I like our 42x0 and 43x0 series fixing films and grease better than HP's.
More info on the swing plate assembly: