Procedures

TPO FLEXIBLE PLASTIC (FRONT AND REAR BUMPER COVERS)

Thermoplastic olefin (TPO) is a soft thermoplastic used for exterior applications where flexible characteristics are required in order to absorb minor impacts without sustaining damage. Special attention must be given to materials as well as procedures when repairing TPO. Among these are the need for adhesion promoters and epoxy based repair materials.

Level 1

Refer to refinish procedures for detailed instructions.

Level 2

Cosmetic damage, minor scratches and gouges.




1. Clean repair area with soap and water followed by grease and wax remover. Wipe dry.
2. Use a two or three inch #50 grade disc to enlarge the damaged area.
3. With a random orbital sander fitted with a #180 grade disc, remove the paint film from the surrounding area to be filled. The repair material should not overlap the painted surface.
4. Apply a double wet coat of 3M(R) Polyolefin Adhesion Promoter-#5907 to entire exposed area.
5. Mix 3M(R) Flexible Parts Repair Material-#5900 according to instructions and apply to the repair area with a squeegee or plastic spreader. Build the material slightly higher than the undamaged surface. Allow repair material to cure 20-30 minutes at 16 degrees C to 27 degrees C (60 degrees F to 80 degrees F).
6. When material is cured, shape repair material with a curved tooth body file. Sand with grade 180A Stikit gold disc followed by grade 240A Stikit gold disc.
7. If low areas or pin holes remain, first apply 3M(R) Polyolefin Adhesion Promoter #5907 or equivalent, then mix and spread additional repair material as in step 5.
8. Apply one coat of PPG DPX-800 Polypropelene Primer over the exposed bare substrate. Allow to dry 10-15 minutes.
9. Apply primer surfacer with flex as outlined in "Flexible Parts Refinishing" and block sand.

LEVEL 3

Damage in the form of small cracks or punctures.

Due to the flexible characteristics of TPO it is necessary to reinforce all cracks and punctures which penetrated the substrate with the following recommended procedure. This process is also useful for repairing attaching surfaces which are cracked or broken away.




1. Clean the backside of the repair area with soap and water followed by grease and wax remover. Wipe dry.
2. Align and secure the piece on the face side with body tape and clamp.




3. Sand the backside of the damaged area with a #50 grade disc and scuff the surrounding area with #180 grade abrasive.
4. Apply a double wet coat of 3M(R) Polyolefin Adhesion Promoter #5907 to prepared area of backside.




5. Cut a piece of fiberglass cloth large enough to overlap the damage 38 mm (1-1/2 in.).





6. Thoroughly mix a quantity of 3M(R) Flexible Parts Repair Material-#5900 and apply a layer around the damage area the approximate size of the fiberglass cloth.
7. Lay fiberglass cloth on a clean surface and use a squeegee or plastic spreader to force the repair material into the weave of the cloth.




8. Apply fiberglass cloth patch to backside of repair area.
9. Apply additional adhesive over surface of fiberglass cloth patch. Allow 20 to 30 minutes cure time at 16 degrees C to 27 degrees C (60 degrees F to 80 degrees F).
10. Remove body repair tape from front side and grind a V groove along the damaged area with a #50 disc.
11. Repair the front as outlined in Level 2 repair.