Lapping films are thin polyester films coated (resin bonded) with tightly graded abrasive particles such as aluminum oxide, silicon carbide, cerium oxide or diamond. The popular particle grades (particle size measured in diameter) are 0.05, 0.1, 0.3, 0.5, 1, 1.5, 2, 3, 5, 6, 9, 12, 15, 20 and 30 microns. (One micron is about 1/50 of a human hair diameter)

The applications for lapping films range from polishing fiber optics, optical components, ceramic capacitors, computer hard drive read-write heads, ceramic seals, etc. The main characteristic of lapping films is that they produce very flat surfaces, especially across materials having a wide range in hardness.

What are lapping films used for?

Lapping films are used for lapping and polishing a substrate to achieve super-fine, highly consistent finishes. Their major applications include fiber optic connector polishing, magnetic heads, floppy disks, magnetic media, metals, plastics, oxide disks, etc.

Why are diamonds used in these lapping films?

Diamond is one of the hardest materials on earth. So diamond particles are used to polish some very hard materials such as ceramics, glass, carbide, composites, exotic alloys and other hard materials that aluminum oxide, silicon carbide or other abrasive materials can not handle.

What kind of substrates can 3M diamond lapping film polish?

3M diamond lapping film can be used on ceramics such as zirconia (material used on fiber optic connector ferrules), glass, carbide, stone, exotic alloys, etc.

Are there alternative materials than diamonds?

Yes. Lapping films with other type of abrasive particles such as aluminum oxide, silicon carbide, cerium oxide are even more popular because of their low cost.

What are the advantages of using 3M diamond lapping films instead of cheaper aluminum oxide or other abrasive lapping films?

1. Long life

2. Produces superior surface finish

3. Reduces overall process time

4. Produces high yields

5. Consistent results throughout life of product

What forms are available of these lapping films?

3M diamond lapping films come in shape of sheets, discs and rolls. The maximum width is 12 inch. The most popular sizes used in fiber optic connector polishing include 4 inch disc, 5 inch disc and 6x6 inch sheet.

The 3M diamond lapping film color code for diamond grit size

Each lapping film manufacturers may use their own color code to distinguish between different particle sizes. For 3M diamond lapping films, the color code is as follows:

0.1 micron - green, 0.5 micron - white, 1.0 micron - lavender, 1.5 micron - light green, 3.0 micron - pink, 6.0 micron - brown, 9.0 micron - blue, 15.0 micron - orange, 20.0 micron - burgundy, 30.0 micron - green, 45.0 micron - amber, 60.0 micron - amber

How do you store 3M diamond lapping films and what are their shelf lives?

Although the storage of lapping films usually do not require special condition, the recommended storage temperature is 10~32°C, relative humidity if 30~70%. It is recommended that the product should be used within 2 years of purchase.

3M Diamond Lapping Film Discs are available for wet or dry (W/D) applications with Pressure Sensitive Adhesive (PSA) or Plain Back from 0.1 micron to 45 micron. Special size orders are also available.

3M Diamond Lapping Film Discs or Sheets have a longer life and are recommended for critical applications. Available in discs and sheets from 0.5 micron to 9 micron. Special size orders are also available.