So what is a grinding disc/wheel?
Seems pretty obvious right? It’s a disc, usually 115mm in diameter, varies in thickness, composed of bonded abrasive material which is used for cutting, grinding and finishing metal or other objects.
What is a flap disc then?
This is also an abrasive wheel, usually 115mm in diameter but rather than being composed of bonded abrasive material, rather the abrasive properties are gained from overlapping abrasive paper which are bonded to a central fibreglass disc.
Don’t they both do the same thing?
Yes, technically, they both do perform the same function. They are both used for grinding metal and are both really, really good at doing that job. The stock removal rates for both are great (beware, like most things, they quality will vary) last for a reasonable length of time, the grinding disc arguably longer and are fairly inexpensive to buy as a consumable item. They both come in a number of variations whether diameter, thickness or grit (abrasiveness grading)
Why use a grinding disc?
Grinding discs are great for stock removal on flat heavy metal, where long welds require grinding, especially where two pieces have been fused together. They are also usually longer lasting bug beware there are a lot of poor quality products out there.
So….flap discs then?
Well, if you need flexibility or if the job requires a finer finish then flap discs are the tool for you. Blending, polishing and de-burring are all easier with the flap disc, the design allows you to manipulate the disc to work in more spaces than a grinding disc. The flap disc is available in a number of grits, or abrasive grades, meaning it is more versatile in engineering. The finer grits by virtue of the fact that they are less aggressive will tend to last a lot longer. They are also considered to be a lot safer as if they were to degrade under high RPM they would be less likelihood of serious injury than the much harder grinding disc.
I hope this helps clear up the differences between the two, it is always worth remembering that there are a huge number of brands out there and they are not all the same. You can buy a cheaper product but you will inevitably be disappointed. Always best to go with a trusted, recognised brand. That’s why we will only work with tired and (literally) tested suppliers.