Henkel 661

Surface Preparation

Minimal Surface Preparation Required.

The 661 adhesive requires no surface preparation on most metal, ferrite, and glass surfaces. For optimum bond strength on metal parts the surface should be washed with a solvent or cleansing solution, abraded with an abrasive pad, and then rinsed with a solvent or cleansing solution. Glass surfaces should be cleaned with a commercial glass cleaner before bonding. Painted surfaces should be abraded lightly and then wiped clean.

Application

BONDMASTER's Equipment Group has a complete line of industrial dispensing equipment to dispense the 661 in magnet bonding applications. Equipment is available to dispense the adhesive through BONDMASTER's unique External Mix dispensing process. The External Mix Dispensing System is a technology that results in high performance without the use of a static mixer. This allows the use of the adhesive in high-speed production without having to change static mixers frequently. The External Mix technology also provides the user with a higher performance than conventional bead on bead systems.

Mixing

For optimum performance, 661 should be mixed in a 1:1 (A:B) ratio. However, the adhesive has a very forgiving mix ratio, and complete cure can be achieved even when the adhesive is not mixed exactly in a one to one ratio.

BONDMASTER 661 Part A & Part B should not be mixed in large quantities, as a vigorous chemical reaction will occur generating a significant amount of heat and vapors.

Curing

Exposure to air will inhibit the cure of all acrylic adhesives. Because of this inhibition, the exposed surface of any mixed adhesive squeezed outside the bondline will remain tacky for a few hours. Only the cure of the exposed surface is inhibited, not the adhesive in the bondline.

Clean-Up

Unreacted Part A & Part B can be cleaned up using acetone, isopropanol, or MEK.