Wiper skipping/grinding on windshield

[purplegreendave]

2008 Mazda 3 Hatchback. I think the trim is GS but I'm not 100% sure.
Passenger side wiper has been skipping across the windshield for a while, it's got quite bad now and has even started scuffing/scraping the glass. I suspect the wiper arm is bent, maybe from trying to move snow with them. It's hard to tell for sure though because I have nothing to compare it to. The problem has persisted across more than 1 set of blades, and I can't see any other adjustments from a cursory glance around the car.

My first instinct is to just try and unbend it, but I'm afraid of overdoing/snapping an already bent (weaker) piece of metal. I imagine replacing the arm wouldn't be too hard, but I'm also not sure where to pick one up (I'm actually in BC not Toronto but this was an active Canadian board so I made an account). Ideally an online shop - WrenchMonkey has one for $65, which turns into $90 after tax + shipping. Any other reputable online sources where I might find the part?

[TheMAN]

if you're saying the arm was bent, that's the cause of the problem... wiper arms needs a certain amount of tension and angle to work effectively... a bent arm or missing/worn spring will cause issues

all you have to do is go to the dealer and buy a new arm... if there's anything else on your car that needs replacing, and you're not sure where to find the part, check the dealer!

[SonicBoy]

Are you sure it's the wiper arm and not the actual windshield?

Take a look at this video:

.

You could also try and clean and treat the wiper however you mention you've changed them and same thing.

[TheMAN]

there's special glass buffing compounds you can buy and it works great removing oil film (which causes blade chatter)... I rather use those than a steel wool