Acrylic Adhesives

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Handling/

Curing

Information

Directions for Use

1. For high strength structural bonds, paint, oxide films, oils, dust, mold release agents and all

other surface contaminants must be completely removed. The amount of surface preparation

depends on the required bond strength, environmental aging resistance desired by user. For

suggested surface preparations on common substrates, see the section on surface preparation.

2. Mixing

For Duo-Pak Cartridges

3M™ Scotch-Weld™ Acrylic Adhesives DP805 and DP820 are supplied in a dual syringe

plastic duo-pak cartridge as part of the 3M™ EPX™ Applicator System. To use, simply insert

the duo-pak cartridge into the EPX applicator and start the plunger into the cylinders using

light pressure on the trigger. Next, remove the duo-pak cartridge cap and expel a small amount

of adhesive to be sure both sides of the duo-pak cartridge are flowing evenly and freely. If

automatic mixing of Part A and Part B is desired, attach the EPX mixing nozzle to the duo-pak

cartridge and begin dispensing the adhesive. For hand mixing, expel the desired amount of

adhesive and mix thoroughly. Mix approximately 15 seconds after uniform color is obtained.

For Bulk Containers

Mix thoroughly by weight or volume in the proportions specified on the product label or in

the typical uncured properties section. Mix approximately 15 seconds after uniform color is

obtained.

3. For maximum bond strength, apply adhesive evenly to both surfaces to be joined.

4. Application to the substrates should be made within 2 minutes for Scotch-Weld acrylic

adhesive DP805 or 15 minutes for Scotch-Weld acrylic adhesive DP820. Larger quantities

and/or higher temperatures will reduce this working time.

5. Join the adhesive coated surfaces and allow to cure at 60°F (16°C) or above until completely

firm. Heat up to 120°F-150°F (49°C-66°C) will speed up curing. Scotch-Weld acrylic adhesive

DP805 will fully cure in 8-24 hours @ 73°F (23°C) and Scotch-Weld acrylic adhesive DP820

will fully cure in 24-48 hours @ 73°F (23°C).

6. Keep parts from moving during cure. Contact pressure necessary. Maximum shear strength is

obtained with a 3-5 mil bond line.

7. Excess uncured adhesive can be cleaned up with ketone type solvents.*

8. Once Scotch-Weld acrylic adhesive DP805 has been applied to a surface, it is best to join the two

mating surfaces together as soon as possible. The reason for this is that after approximately one

minute Scotch-Weld acrylic adhesive DP805 may begin to form a very thin “skin” over the

exposed surface. If left exposed long enough (2-3 minutes), a thick enough “skin” may form

which will inhibit the proper wetting needed to achieve maximum performance. In instances

where an extended exposed open time is required, it is still possible to achieve excellent bonds

by coating both substrates to be joined and making the bond in such a manner as to rupture the

“skin” surface. Scotch-Weld acrylic adhesive DP820 does not exhibit this skinning characteristic.

*Note: When using solvents, extinguish all ignition sources, including pilot lights, and follow the

manufacturer’s precautions and directions for use.

Adhesive Coverage: A 0.005 in. thick bondline will yield a coverage of

320 sq. ft./gallon (typical).

an EPX static mixing nozzle, according to manufacturer’s directions. Thorough hand mixing should offer

comparable results.