Help! My Circular Saw Won't Cut Straight - Blade Wobble?

So I'm in the middle of a project and my circular saw started making this weird noise and the cuts are all wonky. I checked the blade and it seems tight, but it looks like it's wobbling when I spin it by hand. Could it be the arbor? Or the bearings? Any ideas before I take it apart?

Could be a few things. If the blade is wobbling, first check if the arbor nut is really tight. Sometimes they loosen up. Also, make sure you're using the right blade for the material - a dull or warped blade can cause that too. If it's not the blade, might be the bearings. I had a saw that did that and it was the lower bearing going out. Replaced it and it was fine. If you're not sure, maybe take it to a shop for a quick look.

Definitely check the arbor and the flanges. If the blade is mounted with a warped flange or the arbor is bent, it'll wobble. Also, check the blade itself for any bends. Put it on a flat surface and see if it rocks. If the blade is fine, then it's likely the bearings or the armature shaft. If you're handy, you can disassemble and inspect. Just mark the orientation of everything before you take it apart. Also, check for any play in the spindle - if it moves side to side, that's bad.

I've seen this many times. Old saws often have worn bearings that cause wobble. If you're comfortable, take the blade off and spin the arbor by hand. If you feel any roughness or play, it's bearings. I'd recommend replacing them - it's a straightforward job if you have the right tools. Also, check the blade washer - if it's not flat or has a burr, that can cause wobble too. And make sure you're using the correct blade for the saw - some blades have different arbor sizes and you might need a bushing.