Features of each pellet shape

Pellet Recommended Workpiece and Features
  • It is used to grind relatively soft products like ceramic, glass or brass.
  • It contains less diamond compared to square shape, so grindability is lower.
  • It can be applied to all types of workpiece.
  • It contains more diamond compared to round shape, so grindability is higher.
  • It can be applied to all types of the workpiece.
  • Especially it is used to smoothly release chip of large workpiece.
  • It is usually used when using CBN wheel.
  • It is applied when using products with the soft ground surface (when using soft particles)
  • It has less area of epoxy, so it gets less scratches.
  • The arrangement polishing grooves on epoxy area after reclaiming
  • Smoothly releasing chip
  • Easy chip releasing
  • Good grindability
  • Longer dressing period
  • It can be the cause of scratches.
  • It is easy to polish small workpiece.
  • Pellet is less damaged by the impact.
  • It is helpful to improve roughness of workpiece
  • Chip releasing is not smooth, so dressing period can be short.

List of Size of Micron Powder

SYD wheel can be applied to various grit size ranging from #80 ~ #15000.

Nominal dimension
Special grade American Standard
Association grade
F.E.P.A Size
Grit size #
0-1/2 1/4-1 60000 Polishing
0-1 1/2 28000
0-2 1/2-20 1 M1.0 14000
1-2 M1.6 13000
1-3 2-3 M2.5 12000
2-4 2-5 1-5 3 M4.0 8000
3-6 2-6 4-6 5000
4-8 6 M6.3 3000
5-10 6-10 2200 Lapping
6-12 8-12 9 M10 1800
10-15 3-16 8-15 1400
10-20 10-18 M16 1200
12-22 B 12-25 8-22 15 1100
15-25 15-30 1000
20-30 B 15-30 20-25 M25 800 Grinding
22-36 A 25-27 30 700
30-40 B 28-41 35-45 M40 600
36-54 A 40-50 30-60 45 500
40-60 400/500
54-80 40-80 60 M63 325/400
60-100 270/325

Roughness and Surface Flatness of Workpiece

Surface Flatness and abrasive grain of polished side of wheel made by vitrified diamond & CBN have direct impact on workpiece. SYD super vitrified wheel is made in 0.02mm of flatness when released, so it can help customers’ products be polished more precisely.

How to correct wheel

Wheel gets surface flatness or one-sided wear due to various conditions including dressing, how to use, location of workpiece or materials of workpiece. If such phenomenon is ignored and the work is continued, polishing time is increased reducing life cycle of wheel and precision due to serious product variation causing defects. Therefore, surface flatness of wheel should be regularly checked to improve productivity.

The picture below is to understand and modify the variation of wheel. When polishing, if wheel and carrier are rotated only in one way, polished sides of wheel are changed like the picture below. When dressing, alter the direction of lower wheel and carrier to maintain surface flatness of wheel.

Variation of wheel When dressing, alteration of the rotating direction
  • Alter the working condition to make lower wheel and carrier in the same direction
  • ex) upper: CW, lower & carrier: CCW
  • upper: CCW, lower & carrier: CW
  • Alter the working condition to make lower wheel and carrier in the opposite direction
  • ex) upper & carrier: CW, lower: CCW
  • upper & carrier: CCW, lower: CW

When using SYD wheel, one-side wear can happen due to conditions like location of workpiece, pressure, etc. Therefore, please be extremely careful for using and managing wheel.

Wheel performs high grindability reducing polishing time below 1/10, maintaining excellent precision and resolving defects fundamentally. It is important to improve work efficiency in accordance with proper polishing conditions to keep such excellent performance.

1. Relationship between grit size and roughness of ground side

If grit size is big, workability is increased. If ground side is rough and grit size is small, roughness is better, but workability is decreased. Therefore, it is important to select proper grit size for characteristics of workpiece to improve productivity.

2. Pressure

Optimized pressure is one of critical conditions for increased workability and roughness and defect removal in case of polishing flat surface. But, if the pressure is higher than the normal level, workability is better, but workpiece is damaged or the side is rough compared to grit size. (Optimized pressure can be different according to materials of workpiece.)

3. Cutting fluid

One of features of SYD wheel is that when polishing, lubrication is performed by water and cooling not oil. However, according to the type of workpiece, grindability will be higher by adding proper amount of cutting fluid.

※ CBN wheel uses large amount of cutting fluid.