Benchmark Abrasives 4.5" x 7/8" Premium High Density Jumbo Zirconia Type 29 Flap Disc 40 Grit - 10 Pack

I have a metal shop in my garage where I make a variety of metal art, and I am constantly using flap disc. These are not the least expensive disc out there because of their thickness and density. They are well-made and they do last longer than the very cheap and thin disc that are out there. I use them frequently and they work well. Given the nature of what they are I do not expect them to last for a terribly long time, but it is what it is and they do a good job.

Great disc , last decent , grind off material really well

Good quality, price and quick delivery.

Very good flap disc, last a long time.

I recently ripped out carpet from a very old tongue and groove floor — a floor that had two decades-old layers of paint. The paint was not peeling, the tongue and groove installation was not level, and for various reasons a floor sander was not a viable option. After trying 40 grit paper with both a belt sander and a random orbital, I resorted to these flap discs on an angle grinder. The difference was stark. I am getting much better results from the discs (it's not even close) and working much faster (again, it's not even close). There are however a few caveats. First, sanding wood with these is MESSY. While the sanders have a modicum of dust collection, the angle grinder does not, and these discs spit up a LOT of sawdust. At least twenty times messier than using a sander is my estimate. Second, compared to an orbital sander or even a belt sander, sanding a large surface with an angle grinder is really hard work and requires a fair amount of hand and wrist strength. Third, an angle grinder, even with a sanding disc as opposed to a cutting wheel, is a much more dangerous tool than a sander, and sanding is really only a viable option if you remove the safety guard. So you have to use good sense and have decent skills if you want to undertake this. You'll also want to protect your eyes. Fourth, sanding your floor this way can gouge it up pretty bad very quickly, especially if you're trying to remove paint from deeper pockets, which requires more angle. If you don't want a distressed look, or if you're unwilling to spend the time to sand out gouges, this is probably the wrong tool for you. But in my case, these drawbacks were well outweighed by the benefits. I am looking to dye the floor, not paint it, and I really wanted to get the paint off, including near the edges of the grooves and other spots where my belt sander and random orbital sander really struggled to get to bare wood (and only with a lot of time investment). And given the circumstances with this floor, which is patched and was not cleanly installed to begin with, I'm perfectly happy with a little bit of a distressed look. One more advantage: if you have nails or screws you can't get out or further in (or that you just plain missed), they will rip your sandpaper to shreds. With these discs, you can easily just grind them down. (Be aware though that grinding creates a lot of sparks.) How are the discs holding up? I had about 400 square feet to sand, and I estimate I'm close to 3/4 done. I probably could have swapped more frequently; nor have I attempted any method to clean out the discs of gunk (other than banging the disc on the floor a couple times), and I just put the third disc on prior to quitting for the day. If these discs were $8 or $10 each, I'd probably be dissatisfied with that, but given the price of this pack, I'm really happy with that sort of cost–longevity ratio. In my opinion, these are giving really good value. As I indicated, not everyone will want to use these on their floors. But in the right circumstances, this is a great option.