Corrosion Control

Industrial Wash Primer
Sherwin Williams P60 G 2, R7 K 44

Lee H. Erb
EAA Chap 1000 Det 5, Arlington TX

Originally published March 1998

(The subject primer was brought to our attention by Chapter 1000 member Ed Dutreaux)

Industrial Wash Primer, P60 G 2 is a fast drying, pretreatment type, 2-package acid catalyzed vinyl washcoat. The purpose of this Sherwin Williams product is primarily to provide excellent adhesion of top coat paints.

I have not used this product but Sherwin Williams provided a data sheet. Most of the words below are from that data sheet. My comments will be noted later.

Advantages

Promotes excellent adhesion.

Serves as a tie coat over non-ferrous metals (aluminum, brass, copper, and magnesium), ferrous metals, and zinc coated steel.

P60 G 2 is an excellent primer for many enamel topcoats such as Kem Lustral®, Fast Production Enamel, Quick Dry Enamel, Acrylic Enamel Systems, Polane®, and Dimenso®.

Non-photochemically reactive when reduced 150% with Reducer R7 K 44. Do not use any other reducer.

Product Limitations

Catalyst reducer, R7 K 44, is the only reducer to be used with Wash Primer P60 G 2. It must be reduced 150%.

Zinc coated or galvanized steel comes in many forms, therefore, the coating system should be thoroughly checked before final recommendation.

Do not apply P60 G 2 over sand blasted metal. P60 G 2 does not have enough solids to cover the blast profile and to provide suitable protection.

After addition of R7 K 44, the primer must be used within eight (8) hours.

Safety Cautions

Contains Ketones, Alcohols, and Zinc Chromate. Flammable. Vapor harmful if inhaled, may affect the brain or nervous system, causing dizziness, headache, or nausea. Irritates eyes, skin, and respiratory tract.

Volatile Organic Compounds (VOC)

P60 G 2 as reduced for application 150% by R7 K 44, has 6.2 pounds per gallon. (Where I live, Det 5, Arlington, TX, the four-county area is limited to 3.5 pounds per gallon. Therefore I can not use it.)

Personal Comments

My understanding is that the wash primer functions between a chemical film (chem film) coating and an epoxy primer. For industrial use (where permitted) I can see many valid commercial uses including cutting finishing time/costs.

I cannot recommend it for the homebuilder primarily because of the danger of inhaling the vapor by someone (maybe kids, dog, or cat). Although not proven, I believe that chem film and epoxy primer will provide a stronger deterrent to corrosion.

Thanx

Thanks to Ron Yarborough for keeping me informed on EPA and OSHA rules.


EAA Chapter 1000 Home Page
E-Mail: Web Site Director Russ Erb at erbman@pobox.com

URL: http://www.eaa1000.av.org/technicl/corrosion/wash.htm
Contents of The Leading Edge and these web pages are the viewpoints of the authors. No claim is made and no liability is assumed, expressed or implied as to the technical accuracy or safety of the material presented. The viewpoints expressed are not necessarily those of Chapter 1000 or the Experimental Aircraft Association.
Revised -- 24 September 1998