Scotch-Brite Clean and Strip XT Pro Disc - Rust and Paint Stripping Disc - 4.5” diam. x 5/8-11 Quick Change Thread - Extra Coarse Silicon Carbide - Pack of 1

Lasted for about 50 seconds before worn down to nothing, yep I timed it... Went back to standard wire, and flapy disk for rust/scale removal.

I especially like that it sticks a bit out from the grinders protective shield, allowing to put it down horizontally. Pretty aggressive on wood though, need to touch down very gently.

I removed mill scale from a price of 1/2” plate. The disks work best if you use light pressure and take your time. If you are pushing really hard they break down quicker and the amount of mill scale you remove per disk greatly decreases. Working from the edges of the mill scale also works best, rather than starting on top of a solid mill scale area.

I used this to remove *heavy* mill scale from all the surfaces of a 10” piece of W8x40 I-beam. It took probably 65% of the disc to do it but it did an outstanding job. 3M states it’s only for light mill scale; mill scale doesn’t come much heavier than what I used it on. And no danger of cutting into the good steel or dishing it.

I took a chance on this disc, but Im glad I did. Eventually, I clogged this up by accidentally grinding into something sticky, but until then it did fantastically at removing paint and mill scale. This model threads onto a threaded arbor. My angle grinder has bushings, so when I reordered these, I went with a 10 pack of the unthreaded ones. Theyre a bit cheaper.

These are pricey but for people like me that need a quiet, fast stripping blade this is great. For small panels like doors and fenders this works super fast and somewhat quieter than other options for stripping paint and filler. I’m in an urban area so noise levels are a big concern so I don’t mind spending a little more on a quality blade.

Like the way it removes surface rust on a old 1950 car that has rust completely over entire body. Also like that you can spin it 10,000 rpm on a angle grinder. It does appear to be wearing a little fast and I am not pressing on it just laying on the panel. You don’t have to worry about particle buildup using this. Also it is threaded and spins right onto your grinder.

I have pretty much every kind of grinding and finishing tool, and probably 30 electric tools: disc sanders, angle grinders, D/A, orbitals, air grinders, what have you. Metal worker for 40 years. Honestly these discs are pretty amazing. First encountered them on a drum type surface conditioning tool meant for metal brush finishing. Used that machine on some aged wood with old paint - super fast and smooth finish. Went looking for a disc style because its smaller and more versatile. Sandpaper and grinding discs are slow and wear out fast in comparison to these. They dont load up with paint so amazing stripping paint from wood, metal, concrete. I bought these specifically for a basement upgrade project. To clean concrete residue from timber, which is a slow job with a regular sanding disc or D/A. Could use a wire wheel but they are slower and dig out the grain a lot more. And discovered on the same project that these are perfect for stripping old paint off the concrete floor, and for cleaning the concrete walls. Those are all tough jobs with few quick solutions. Awesome. (If rather a dusty job!) I went with 3M because the discs last a long time, and 3M is not generally the cheapest but their sandpaper usually lasts the longest. This will clean rust and paint off concrete and stone like nothing I have seen. Leaves a fairly smooth finish. The grades of these are oddly named. The green one is coarser, more aggressive, but leaves more scratches. The purple one looks almost identical but leaves a finer finish. I would probably go with purple first but if it seems slow switch to the green. Rust is easy with these things but mill scale on steel is about the toughest coating on earth to remove. I would think green better because its more aggressive. Scale will still wear these discs out. A grinding stone disc wears longer but bounces around and leaves a much more scarred up surface. For stripping paint and rust, cleaning stone and concrete, metal finishing, lumber cleaning, bbq grills - this is hands down the one disc I would recommend most people have in their tool shed. The only negative thing I would say is that a mini-grinder tends to spin at over 10,000 rpm which is just too fast. I put these discs on a 5 Makita sander that runs about half that and its much easier to control, but the arbor needs to be adapted which is a longer story. If you can find a mini grinder with adjustable speed that would be ideal but they are not common.

Be careful here.3m part number 29900 is not silicon carbide,it’s aluminum oxide.

Removes paint and mill scale without marring the underlying steel better than anything Ive ever used. Durable. Worth the price for a quality product.