3M 7000044840 Diamond Lapping Film 668X 1.0 Micron Psa Sheet

Product Description

The 3M 7000044840 is a pressure-sensitive adhesive (PSA) diamond lapping film designed for precision surface finishing of extremely hard materials. Precisely graded 1.0 micron diamond particles are uniformly coated onto a dimensionally stable polyester film backing, delivering a consistent, repeatable finish with each pass. The PSA backing allows the sheet to mount securely to a flat lapping plate or fixture without additional adhesives or fixturing hardware. This product is used by machinists, tool-and-die technicians, fiber optic technicians, and precision instrument specialists who require controlled, measurable material removal on hard substrates.

The 668X film is suited for fine finishing and polishing applications on carbide, ceramic, glass, hardened steel, and optical or fiber optic components. At 1.0 micron particle size, it falls within the fine-polishing range, producing smooth surface finishes with tight dimensional tolerances. Each sheet measures 9 inches x 11 inches, making it compatible with standard lapping plate setups and manual polishing fixtures. The PSA backing simplifies sheet changes in production or field-service environments where repeatability and speed matter.

Key Features

• 1.0 micron precisely graded diamond abrasive for consistent, repeatable material removal
• PSA backing mounts securely to flat lapping plates without separate adhesives
• Polyester film backing provides dimensional stability under lapping pressure
• 9 inches x 11 inches sheet size fits standard lapping plate formats
• Effective on extremely hard materials including carbide, ceramic, and hardened steel
• Available across a broad micron range from 0.10 to 30.0 micron for multi-stage finishing sequences

Compatibility

Designed as a PSA-backed alternative to the 3M 661X diamond lapping film series, suitable for use on flat lapping plates and fixtures used in precision machining, fiber optic polishing, and hard-material surface finishing applications.

Installation Notes

Surface preparation is critical before applying the PSA sheet — the lapping plate should be clean, dry, and free of oils or debris to ensure full adhesive contact. Peel the liner and apply the sheet smoothly from one edge to avoid air bubbles that can cause uneven lapping. When sequencing through multiple micron grades, clean the workpiece thoroughly between grades to prevent cross-contamination of abrasive particles. Technicians should follow facility safety practices for handling fine abrasive media, including appropriate eye protection when dry lapping.

Technical Specifications

• Abrasive Type: Diamond
• Particle Size: 1.0 micron
• Backing Type: Polyester film
• Attachment Method: Pressure-Sensitive Adhesive (PSA)
• Sheet Size: 9 inches x 11 inches
• Weight: 0.02 pounds
• Sold As: Each
• Minimum Order Quantity: 10
• UPC: 00051111499856

Standard Information

• Brand: 3M
• Manufacturer Part Number: 7000044840