Flap wheel alternative for weld prep

[AlphaHare]

I saw a fabrication video and glimpsed this product from 3M. I got one from Amazon and tried it out today.

This is the freaking bomb. It took off mill scale and rust about 90% faster than with a flap wheel - it blew my mind. Great finish, no real metal removal.

https://www.amazon.com/dp/B07L1CXBRZ?

We'll see how long it lasts. It's not cheap at $22, but good quality flap wheels are nearly the same. But as a time saver - wow am I impressed.

Caveats:

I need to get a respirator - I should have one already but the barn I work in is, shall we say, well ventilated. This throws a lot of dust.
Do NOT get near sharp edges in tight corners. This thing will grab and launch your grinder out of your hands. First time for me in 30 years.

 

[Mr P]

How does it compare to a wire wheel?

 

[AlphaHare]

Honestly don't know. I haven't used a wire wheel in a long time - I've never found them that great. Maybe I should revisit that.

 

[nikitis]

I use wire wheels and they are pretty cheap and you can get different sizes in a pack too, Skinny ones for corners, medium sized ones with nothing in the middle for rounded surfaces, then the wide ones for large flat surfaces. Rust comes right off quick too.

I used a medium sized wire wheel the other day on my trucks ball hitch, as it was rusting, and it make it nearly like new.

I've used that pad as well by 3M, it's really mostly good for large flat surface areas, not for tight or rough spots as you pointed out.

 

[Rucker]

I have two angle grinders, one small, one large. For scale removal I use a cup wire wheel. Both require strong arms. The larger angle grinder cup wire wheel is huge and you can't screw around when you're grinding but it works the best for heavy work.

 

[Cheezewhiz]

Ah, nice to hear those things are decent. I've never tried em, because price, and I know my other stuff works.

How long do they last, compared to flap discs/wire wheel?

 

[AlphaHare]

I'd want to try a couple more before I say anything definitive, but my first wheel is clearly wearing faster than a flap wheel. I did chew it up a bit at first when I launched my grinder....

I'm guessing that I wont keep using them unless I want to treat myself. I suspect they have a good commercial use case where the time savings would more than pay for the difference especially as they leave a paint-ready finish. A fast 40 grit flap wheel won't do that.

As Nikitis pointed out, these are best at large flat areas, the length of bar stock, panels, also paint prep and paint removal. You can see it deteriorating when you hit a sharp corner.