Rust

[u/dcrey24]

So I have a 93 MR2 and want to work on it but kind of neglected it. So now I'm starting to get back on the grind and the 1st issue I need to tackle is rusting on the roof/rear pillar. Would the best option be grinding and if so, what wheels? I recently acquired a angle grinder for various jobs and wanted the opinions from everyone.

Thanks in advance

[u/_clever_reference_]

That needs to be cut out and fresh sheet metal welded in. That's beyond just some grinding.

[u/dcrey24 → u/_clever_reference_]

Just a simple answer I was looking for, I didn't know if grinding or cut off would be easier to do before welding. There is no denying that welding is necessary here

[u/_clever_reference_ → u/dcrey24]

When I did all my rust repair on my Datsun (there was a ton), I used these on my Milwaukee die grinder. https://link.amazon/B0avZKgKE

A 4.5" grinder with cut-off discs is a bit overkill for sheet metal stuff like this, although it would work.

You'll also want some sanding discs, I used these again on my Milwaukee 90 degree die grinder. They're ok, don't last too long but they're cheap. https://link.amazon/B0hp3J2ZV

These also work really well at removing paint etc but won't cut into the sheet metal, for when you're just trying to clean not cut. https://link.amazon/B09Ojdavt

If you want to see everything i did and what i learned check out my videos www.youtube.com/@blokgarage

[u/dcrey24 → u/_clever_reference_]

Great options and will get these to start working on it. Thanks for the awesome tips

[u/404-skill_not_found]

The straight line of rust is deeply concerning. I don’t know the panels of your rig, but this hints that there’s a broken joint hiding under there.

[u/dcrey24 → u/404-skill_not_found]

Don't know much about it either but the part under the sheet is still very solid (I've been poking at the bubbling that has been going on) but I already know it's going to be a lot of work but don't mind

[u/404-skill_not_found → u/dcrey24]

Well, it could be relatively minor. You’ll get to decide if clearing the rust leaves enough solid material, to trust, behind. Also, an effective (plus dangerous) rust remover is a knotted wire wheel, on the grinder. They dig a little deeper than sanding type disks. The disks need to take down the metal surrounding the rust divots, while the wire wheel can reach down a bit more. Dangerous? Most wire wheels don’t fit with the guard in place. Plus, they’ll shred anything soft that they come in contact with.

[u/geking]

Thats really bad rust. Thats on the b pillar near the engine cover? Totaly a load bearing location. Is it through the outer sheetmetal?

Its gonna need the rust cut out with a cut off wheel, new metal formed and welded in. If it was not a structual part of the unibody I would say use a fibrelass patch but that needs metal welded in there...

[u/TheAmericanIcon]

I mean for aggressive paint and rust removal without removing much metal, wire. Those twisted steel wire brushes you see should do the trick. I like the cup brushes for specific spots like this, a true wheel shape might get away from you a little easier.

You’ll end up messing up that trim piece though if that’s plastic. You’ll have to be extra careful or probably pull that trim so you can get behind it. That’s the part that might be nasty, the hidden rust.

[u/nostradumbass7544678]

Start grinding off the paint until you get back to solid metal, then realize it's in 10x worse shape than you initially thought, and check the prices on rust-free southern shells.