Are they supposed to come with 2 dustwashers, and if so what is the second one for?
Supposed to? Not sure. As far as I know most models do and the second one can, depending on how the stick is mounted, be used as a secondary dust washer between the pivot and the top panel of your case.
yes and its for underneath the top panel if you can fit it. you dont really need it.
It comes with two. Like blind says it isnt nessecary, but I use it just to keep any dust or debris from entering the stick in case the top dust washer fails for some reason. If it fits, use it, if not, dont worry.
Keep both washers.
They are where they are to prevent dust from getting into the joystick pivot. Over time, dust collection can be become serious and gum up the works. Plus, you paid for that plastic – why throw it away when it’s good for something?
The only time I’ve ever NOT kept the bottom dustwasher in place is on my Tekken 5 sticks (can’t fit well under the standard Hori mount on that faceplate – not enough clearance for smooth movement) and on the LS-32’s that I modded JLF-CD’s for. In both cases, I just doubled up the washers on top of the faceplate.
Again, I hate throwing away stuff I paid for!
(In the end, I modded my T5 faceplates to remove those awful Hori joystick mounts. I’m keeping one JLF [on one of my personal T5 joystick cab’s] with a free-moving dust washer underneath the faceplate where it should be!)