Grinding discs and flap discs both fit an angle grinder, but they do very different jobs. Using the right one saves time, gives a better finish and makes the disc last longer.
Grinding discs: fast, heavy removal
A depressed-centre grinding disc such as the 4″ x 6mm grinding disc removes metal quickly. Use it to grind down heavy welds, bevel plate edges and remove large amounts of material. It leaves a rough surface, so it is usually followed by a flap disc if a smoother finish is needed. For bigger grinders there is a 7″ grinding disc.
Flap discs: grind and finish in one step
A flap disc is made of overlapping abrasive flaps. It removes material more gently and leaves a smoother surface, so it is ideal for blending welds, removing rust and mill scale, and finishing edges.
- An aluminium oxide flap disc is a good general-purpose choice for mild steel.
- A zirconium flap disc cuts faster and lasts longer on hard steel and stainless steel.
Cutting discs: cutting only
Thin discs such as the 4″ x 2mm cutting disc are made for cutting, not grinding. Never use the side of a cutting disc to grind: it can shatter.
Flap wheels and mounted stones
For inside corners, pipes and small areas, a flap wheel or mounted grinding stone on a die grinder reaches where a disc cannot.
Steel or stainless?
Use discs marked for stainless steel (INOX) on stainless, such as the stainless steel grinding disc. They contain no iron or sulphur that could cause rust spots.
Quick guide
- Heavy weld removal and bevelling: grinding disc
- Blending welds, rust removal, finishing: flap disc
- Cutting bar, plate or pipe: cutting disc
- Corners and inside pipes: flap wheel or mounted stone
Whatever disc you use, follow our grinding and cutting disc safety habits.
Abrasives in Singapore
Fong Yung Industries LLP stocks grinding, cutting and flap discs in the EVO-Abrasive range. Browse the range or request a quote.