SIGNI 5 Pack SiC Plastic Back Grinding Wheel for Granite/Marble/Concrete and Glasses (4.5 INCH, 24 GRIT)

All excellent services and product, good quality product and zero issues.

Works well to clean paint off of cement, only complaint is that it is a little shallow from a height standpoint so you have to have a very shallow dust shroud to make it work. I had to grind off some of the metal bracket on my dust shroud to make the dust shroud lower in height in order for it to work. Could be a crappy dust shroud design from DeWalt so I only took off one star.

30 seconds and the brick was grind down 1/4 Inch. Way faster than I thought it would...

It does the best job on concrete floors that are painted. We tried everything and these were phenomenal!

Made short work of my job

These wheels fit my low-speed grinder (a.k.a. polisher) just fine. Even at only 3600 RPM they do generate a bit of dust, which the vacuum hood picks up, but they also scatter silicon carbide chunks which the hood can't catch. As far as actually grinding goes, these 36G versions aren't the best. I'm trying to remove the thin layer of densifier from my so called "polished" concrete floor so that thinset will stick where I want to lay tile. The slightly open nature of these along with the somewhat flexible and less "jumpy" behavior makes me believe that these would be great for removing paint or gummy mastic from a concrete floor when compared to a diamond disc. However, they fall short when it comes to actually grinding slightly into the concrete. I don't know, could be the choice of 36 grit (which is typical for a diamond grinding disc). Maybe I should have gotten the 16G or even 8G discs. At over $8 each, I'm not sure these are such a great value over budget diamond discs. The disposible nature of them seems appealing, but it's not a plus when they aren't able to do the required job.

Terrible balancing causing the grinder to shake. I wouldn't recommend these even for a cheap grinder as it will be destroyed from the out of balance. The wobble was a 1/4" difference from the side touching the surface and 180° so the disk would destroy itself before all grinding grit would have touched the surface being ground. Returned for refund.

This fits just fine on a standard 4 1/2 inch angle grinder and the grinding disc, being plastic, allows it to be used either wet or dry. It can be used on concrete or other masonry and does an OK job but does not remove material as fast or last as long as wheels that use diamond grit. It does, however, do a pretty good job of removing paint from a cement floor. I tried it out on shaping some pine wood on a 2 by 4 and it does a passable job for that, but if you get too aggressive it will burn the wood. I used it to clean some rust off of some steel plate and it does a pretty effective job on that application (see my video). Since the plastic can compress, when putting it on your grinder, you should take extra care to make sure it is tightend sufficiently. The ones that I used seem to be balanced just fine but I only got the four and a half inch version. These discs are kind of novel and probably are different than the ones you are used to using. But they are an interesting concept and I can see some applications where their distinctiveness could be beneficial. My philosophy is that, for a rating system to be effective, the highest rating and the lowest rating should be reserved for a relatively small percentage of the best and the worst products. I DON'T take into consideration prices or issues with shipping. I stick to a fair and honest evaluation of the product itself. Following is each of the five categories of *stars* and how I assign them to a product: ***** Five stars - Exceeded my expectations. I really love it! **** Four stars - Met my expectations. I like it and recommend it. *** Three stars - Average- some pros but some notable cons. ** Two stars - Disappointed- few pros and too many cons. * One star - Terrible! Stay away from it! I don't often give five stars for something unless I really love it, and I rarely give one star. Hopefully this helps you to understand why I gave my star rating to this product. Thanks for reading my review! I hope it has helped you.