Surface grinding discs - difference between premium and standard?

[bwehman]

I need to clean up a concrete garage floor (remove old coatings, paint, spilled epoxy, etc) and waffling between the standard and premium discs. Any reason to go with one over the other?

 

[dsweetser]

Premium has larger surface area and much thicker. It will last much longer.

 

[bwehman]

Premium has larger surface area and much thicker. It will last much longer.

Gotcha. What do you mean by larger surface area? They both appear to be 130mm.

 

[dsweetser]

The segments with embedded diamonds are larger.

 

[Steve1]

Take care to keep the disc parallel to the floor. 
If you tilt the grinder, you will quickly put circular grooves into the floor.

 

[mino]

As already said. The "PREMIUM" disks have bigger diamond blocks which are also higher.

In general, if you are just chipping-in, get the "normal" disc first.

When/If you get through it, you will know if you want the (longer lasting) "PREMIUM" one .. Also do pay attention to the various types. You are better off with multiple "basic" discs of different types compared to, say, just a single "HARD" PREMIUM one.

By my estimate, the PREMIUM ones last about 3x as the basic ones. Give or take. The geometry makes them also a bit easier to work "straight" when used at low speed, but the difference is small. Both discs type have a huge gyro effect when at full speed that negates this.