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The subject of completely refinishing a car from the metal out has been covered. However, it frequently happens that the old finish is in such condition—or keeping the cost down is so important—that it is desirable to refinish without stripping the car down to the metal.

Have the car and chassis thoroughly washed—the latter, steam cleaned if possible. Then remove the wheels and all outside hardware such as door handles, lamps, bumpers, etc., and take license plates off.

The old finish is then sanded thoroughly with No. 400 paper and high test gasoline. Be careful to avoid scratching the surfaces. Now wipe off the car with a clean cloth and pure turpentine or commercial wax remover.

Any rust spots or breaks in the finish must be sanded out to form a feather edge with the old finish. Then spot glaze these places with a combined surfacer and primer. When dry, sand to level off with the rest of the finish. Deep, sharp breaks in the finish should be spot puttied and sanded smooth.

Now spray both sides of the fenders and hood and the surfaces of the body with one coat of combined primer and sealer. When this is thoroughly dry, spray on two coats of surfacer. After this has dried it should be sanded down with fine sand paper and all dust blown away and the surface wiped carefully.

From this point on, the refinishing job is identical with the procedure outlined for refinishing a car from the metal out.

Inexpensive refinishing

While refinishing over the old finish reduces costs somewhat, there is almost as much rubbing as when building up a finish from the bare metal. And rubbing takes time and costs money.

Finish manufacturers have recognized this and have produced lacquers and enamels that can be used with practically no rubbing. Such refinishing is popular with car owners and in the used car departments.

Such refinishing is invariably done over the old finish. Do not skimp the cleaning job on chassis and motor. Remove door handles and other outside hardware and also wheels. Sand down all surfaces with fine sand paper. Blow off and wipe away all dust.

Touch up all bare metal spots with primer, and when dry give the whole job a coat of combined primer and sealer, sprayed on. If the old finish is very rough a coat of surfacer will also be needed.

Whenever spraying over an old finish, the use of a sealer is very important. This sealer forms a bond between the old and new finishes and keeps the following coats of lacquer from softening the old undercoats. If the undercoats soften, several undesirable things happen. The finish may become roughened—"alligator" surfaced as some call it. Or the finish may not dry as quickly as it should. And if a very heavy first coat of lacquer is sprayed over the old finish, the whole thing may run or sag badly.

After sanding the last undercoat, spray on two coats of black gloss lacquer. Then mask the fenders, splash aprons and other parts that are wanted black on the finished job, and spray the balance of the car with two or three coats of gloss lacquer in the desired colour.

This lacquer need not be rubbed, as it dries with a gloss. However, this gloss can be improved by spraying on a light coat of thinner. The under parts should be sprayed with a coat of chassis black, the body striped, and the job reassembled. Then it may be polished to raise the gloss if desired.

Refinishing right over the old finish is so popular in many sections—and for many reasons—that the step-by-step procedure of two of the outstanding manufacturers of refinishing materials is here given.

From the Duco instructions come the following:

Class B job

Instructions for application of Duco finish over old finish.

  1. Remove door handles, license plates, emblems and drop rear fenders. Remove wheels. If steam pressure is available its use will simplify cleaning operation.
  2. Clean chassis and underneath fenders and wash body and engine clean.
  3. Sand down old finish on the body, using No. 320 paper and gasoline. Dry-sand enamel parts with No. 100 or No. 150 sandpaper.
  4. Mask all window and windshield glass. Spray one coat du Pont No. 1538 Pyroxylin Primer or equivalent material over entire job. Allow to dry twenty or thirty minutes and spray on two coats of du Pont surfacer to body, fenders and hood. Dry from one to two hours or longer if necessary.
  5. Inspect carefully and fill all defects in surface with du Pont No. 1031 Pyroxylin Putty.
  6. Sand out surface with No. 220 wet or dry sandpaper and water, and finish sanding operation with paper No. 280. Wipe off and blow off.
  7. Spray fenders, splash aprons and upper structure of body with necessary coats of selected colour of Duco, which has been reduced with du Pont Thinner. Dry one hour or longer if necessary.
  8. Cover fenders, splash aprons and gas tank with paper, securing with adhesive tape, also mask off upper structure in same manner.
  9. Spray hood and body with thin coats of desired colour of Duco, reduced to proper spraying consistency by using Duco colour and du Pont Thinner. Allow to dry sufficiently and remove masking.
  10. Refinish wheels in accordance with specifications under "Wheel Finishing."
  11. Polish Duco with du Pont No. 2 Rubbing Compound, reduced with water to a creamy consistency, or du Pont No. 3 Rubbing Compound, reduced with kerosene.
  12. Spray chassis, etc., with one coat of du Pont Chassis Black. Stripe with proper colour du Pont Striping Duco.
  13. Reassemble car and clean up for delivery.

And where the cheapest kind of refinishing job is wanted —especially for cheap used cars— Duco advises as follows:


  1. Wash car, chassis and motor. Remove door handles, tires, wheels, etc. Dry-sand body and fenders with paper No. 150. Wipe off and blow off with direct air pressure. Wash surface with high-test gasoline and wipe dry. Cover all glass with du Pont No. 2074 Shieldcote.
  2. Touch up bare metal with du Pont No. 1538 Pyroxylin Primer or a good primer-sealer and spray entire body and fenders with a single coat of same material. If thought advisable on account of imperfections in old finish, apply one coat of a good surfacer. Dry one hour or more as required.
  3. Dry-sand lightly with No. 280 wet or dry sandpaper. Clean up and blow off dust with direct air pressure.
  4. Spray two coats du Pont gloss black, reduced to spraying consistency, on fenders, aprons, gas tank, etc. Allow one hour for drying. Increase gloss by mist coat of thinner, if desired.
  5. Mask off fenders, gas tank and aprons with paper and one-inch adhesive tape.
  6. Spray on two coats du Pont Used Car Gloss Lacquer of desired colour to entire body and hood. This material should not be reduced, as it is furnished at spraying consistency. Increase gloss by mist coat of Thinner. Dry one hour. Used Car Gloss Lacquer should not be rubbed, as it dries with a gloss, which, however, may be increased by polishing with du Pont No. 7 Polish. If preferred, Duco can be used instead of Used Car Gloss Lacquer and the desired gloss obtained by rubbing and polishing in the usual manner, or by spraying a coat of No. 1907 Clear Duco over the entire job.
  7. Brush in raised moulding with du Pont No. 207-412 Striping Black Duco.
  8. Spray on one coat du Pont FV-40 Chassis Black on chassis, gas tank and underneath fenders.
  9. If desired, refinish wheels as covered in Chapter V.
  10. Clean up and reassemble.

Corresponding refinishing jobs done with Opex lacquers—a product of The Sherwin-Williams Company—are handled as follows :

Opex method no. 4

Over old paint or varnish

The success of the application of Opex Enamel over the old paint and varnish depends entirely on the method of application, the condition of the old paint and varnish, and the care of the operator. Thousands of cars have been successfully finished in the following methods over the old finish. We list three methods, each of them having its special interesting feature.

It must be definitely understood, however, that these systems for over the old paint are not offered as a cure-all. The old paint must necessarily be in good condition. If it is peeling or too badly cracked, the paint must be removed to the bare metal. However, for a quick and less expensive method of finishing we know that this system is entirely satisfactory.


Clean and sand off the car thoroughly. All loose paint, grease, oil and dirt should be removed. The adherence of the product to the old paint will be satisfactory, providing rust, grease, dirt, oil are eliminated. However, if you apply Opex to paint which is almost ready to fall off, there is no reason to expect that the new finish is going to hold the old on. Many refinishers are using ammonia to clean off the varnish and then sand off the remaining colour varnish.

1st operation

Apply one coat Oil Metal Primer and Sealer No. 12 or Opex Clear Binder No. 67.

2nd operation

Apply one light dust coat of Opex Binder Surfacer Gray, Light or Dark, reduced with equal parts of Opex Binder Thinner No. 2. This material dries for recoating and sanding in one hour or more.

3rd operation

Apply heavier successive coats, depending upon the condition of the original finish. Usually two or three coats of Opex Binder Surfacer Grey, Light or Dark, are sufficient to give a foundation which, when sanded out, leaves a perfectly smooth finish ready for the application of the Opex Enamel.

4th operation

Sand to surface with fine sandpaper. Deep cuts or scratches should be avoided. A hard, glossy surface should be secured.

5th operation

Apply Opex Enamel two or three coats reduced with Opex Binder Thinner No. 2.

Opex method no 5

For an even quicker and less expensive job the priming coat is eliminated in this method. Of course, if there are any rust spots, these must be sanded out bright and clean and primer applied to the bare metal where exposed.


Clean and sand off the body and car completely, taking all care suggested with regard to oil, grease, etc., as in Method 4.

1st operation

Spray one very light or dust coat of Opex Binder Surfacer Grey, Light or Dark, reduced with equal parts of Opex Binder Thinner No. 2 directly over the cleaned and sanded body.

2nd operation

Apply successive heavier coats of Opex Binder Surfacer Grey, Light or Dark, reduced as above, until sufficient material has been applied to fill surface imperfections.

3rd operation

Apply Opex Enamel, reduced with equal parts of Opex Thinner No. 2 same as suggested in previous methods.

Opex method no 6


At times for the cheapest type of job nothing is desired but a freshening up of the surface after all bare metal spots have been touched up with Oil Metal Primer and Sealer No. 12; Opex Enamel is applied over the old finish without surfacing. The car should be cleaned and prepared the same as in the two previous systems, taking special care that all grease, dirt and oil are removed.

1st operation

Where the old varnish film is not crazed or cracked, and therefore does not require surfacing, we recommend a coat of Opex Clear Binder No. 67, which serves as a bond coat between the old varnish film and the new lacquer. Opex Clear Binder is an especially designed product to serve this purpose.

2nd operation

Spray one very light dust or mist coat of Opex Enamel. reduced with equal parts of Opex Thinner No. 2. A heavy coat will probably raise the old finish. A dust coat if applied properly will never affect the old finish.

3rd operation

Apply two or three additional but heavier coats of Opex Enamel thinned with Opex Thinner No. 2 and bring up the finish the same as in methods previously described.