Structural Adhesive Film

AF 30 (5, 10 and 12 mil)

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Product Application

Surface Preparations

A thoroughly cleaned, dry, grease free surface is essential for maximum performance. Cleaning methods which will

produce a break-free water film on metal surfaces are generally satisfactory.

Suggested Cleaning Procedure for Aluminum

1. Alkaline Degrease – Oakite 164 solution (9-11 oz/gallon water) at 190°F ± 10°F (87.8°C ± 5.6°C) for 10-20

minutes. Rinse immediately in large quantities of cold running water.

2. Optimized FPL Etch Solution (1 liter):

Material

Amount

Distilled Water

700 ml plus balance of liter (see below)

Sodium Dichromate

28 to 67.3 grams

Sulfuric Acid

287.9 to 310.0 grams

Aluminum Chips

1.5 grams/liter of mixed solution

To prepare 1 liter of this solution, dissolve sodium dichromate in 700 ml of distilled water. Add sulfuric acid

and mix well. Add additional distilled water to fill to 1 liter. Heat mixed solution to 66 to 71°C (150 to 160°F).

Dissolve 1.5 grams of 2024 bare aluminum chips per liter of mixed solution. Gentle agitation will help

aluminum dissolve in about 24 hours.

To FPL etch panels, place them in the above solution at 150 to 160°F (66 to 71°C) for 12 to 15 minutes.

3. Rinse – Rinse panels in clear running water.

4. Dry – Air dry 15 minutes; force dry 10 minutes (minimum) at 140°F (60°C) maximum.

5. It is advisable to coat the freshly cleaned surfaces with primer within 4 hours after surface preparation.

Note: Read and follow safety and precautioning recommendations for the components of this etch solution prior to

preparation.

Primer Application

Advantages –

Priming of adherends offer two distinct advantages: (1) insures complete wetting of metal surfaces which normally

results in superior environmental properties, and (2) simplifies production by protecting cleaned parts until bonding

can be completed. Primers have been applied successfully by flow coating, brushing and spraying.

For additional information, please refer to the 3M™ Scotch-Weld™ Structural Adhesive Primer EC-1660 (5%)

Technical Data sheet.

Primer Dry

A primer dry which will result in a solvent free coating is generally satisfactory. Drying temperatures above 300°F

(149°C) should be avoided, since a primer overcure will hinder the wetting action of the adhesive film to the primer.

The following chart lists suggested dry cycles for primers:

Air Dry

Force Dry

Force Dry Temperature

Scotch-Weld EC-1660

30 minutes

30 minutes

225°F (107°C)

The primed surface, after cooling to ambient temperatures, is ready for adhesive bonding. The primed surface should

be protected from contamination introduced by dust, fingerprints, oil, etc.

Film Application

Care should be taken to avoid contaminating adhesive and cleaned or primed aluminum by any substance which will

hinder wetting action of the adhesive.

1. Cut portion of film to be used from roll with protective liner in place.

2. Place film on metal using the liner as a protective cover.

3. Roll film into position with a rubber roller insuring that no air is trapped between primer and film.