Saturn Plastic Repair Information --- Whitepaper
 

Stumbled across this. Seems rather informative.

Problem is it is from 1993 and may not be representative of the later designs and repair and paint approaches.

Unc, seems like it might be of interest to you w your 94.

here's the link

Research Bulletin 1993-5

Here's the pasted text
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Saturn Plastic Repair Information

Introduction

The purpose of this bulletin is to identify and locate all steel and composite body panels used on Saturn vehicles. It will also provide important information concerning the repair and refinishing of these panels.

Exterior Body Panels

Most exterior panels on the Saturn are made of plastic composites which are mechanically fastened to the vehicle substructure. This method of attachment provides a more accurate fit and reduces removal and replacement time as compared to traditional welded-on body panels. The hood, decklid and roof panel are constructed of mild 1008 steel. Both rear quarter panels and front fenders are made of Polyphenylene Ether (PPE). All outer door panels are Acrylonitrite/Butadine-Styrene (ABS)/Polycarbonate (PC) and the front and rear fascias utilize Ethylene/Propylene, Photograph 1.


Four Levels of Physical Damage

The Saturn company lists four levels of damage that can occur to its composite plastic panels:

• Level 1 indicates paint scratches and requires paint refinishing only.
• Level 2 indicates a gouge in the plastic and requires plastic filling and paint refinishing.
• Level 3 indicates a crack or puncture to the plastic and requires plastic reinforcement, filling and paint refinishing.
• Level 4 indicates severe or multiple damage locations which will require replacing and refinishing the exterior body panel(s).

In addition to determining the various levels of repair for their composite body panels, Saturn has classified the composites into two distinct groups: parts made of Rigid Plastic and those made of Flexible Plastic.
Refer to Table 1, under the Identifying Symbol column. ABS, ABS + PC, and PA + PPE are considered Rigid Plastic, while components constructed of PE, PP and E/P/TPO are considered Flexible Plastic.
Accordingly, all rigid plastic components require rigid type plastic repair material and all flexible plastic components require flexible type plastic repair material.

Rigid Plastic and Steel Repair

Level 1 Damage Repair: The following procedure is recommended for correcting paint scratches.

1. Clean component with wax and grease removing solvent.
2. Scuff-sand panel lightly (wet or dry) with #400 sandpaper.
3. Apply metal conditioning to any exposed metal.
4. Apply urethane primer-surfacer, covering all bare surfaces and allow to dry completely.
5. Scuff-sand panel (wet or dry) with #400 sandpaper.
6. Apply color coat.

Level 2 Damage Repair: The following procedure is recommended for the repairs of cosmetic damage, minor scratches and gouges.

1. Clean repair area with soap and water. Follow-up with isopropyl cleaner and wipe the area dry.
2. Grind a 1&1/2" taper around the damaged area using a grade 80 sandpaper on a D-A sander. For deep gouges, use a grade 36, 3 in. disc followed by a grade 80 sandpaper.
3. Featheredge paint around repair and sand repair area with grade 180 sandpaper with D-A sander. Wipe area with a clean, dry rag. Saturn recommends the use of epoxy and urethane based plastic fillers because of their ability to adhere to smooth surfaces.
4. Mix Rigid Plastic Repair Material according to manufacturer's instructions. Apply with a plastic spreader, building the material slightly higher than the undamaged surface.
5. After the material is cured, sand with a 180A grade sandpaper using a D-A sander. Follow-up using a 240A grade sandpaper.
6. Fill scratches and pin holes with a thin coat of Rigid Plastic Repair Material and sand as in step 5.
7. Apply a double coat of Glasurit Glassohyd Sealer 1109 or comparable product over the repair area. Air dry for 1-2 hours at 16 to 27 degrees C (60 to 80 degrees F) or bake at 61 degrees C (140 degrees F) for 30 minutes. Lightly scuff-sand with a grade 320A sandpaper. Wipe with a clean dry cloth.
8. Apply urethane primer-surfacer to entire part and allow to dry completely. Block sand (wet or dry) with #400 sandpaper.
9. Apply color coat.

Level 3 Damage Repair: The following procedure is recommended for repairing small cracks or punctures. If panel damage includes cracking, first drill a 1/8 inch hole at each end of the crack to prevent further cracking.

1. Clean backside of damaged area with soap and water followed by grease and wax remover. Wipe dry.
2. Scuff backside of repair area with 180 grit abrasive.
3. Cut a fiberglass cloth patch large enough to overlap the damage by 38mm (1-1/2 in.).
4. Thoroughly mix structural adhesive and apply (to back side around the damaged area) the approximate size of the patch.
5. Lay the fiberglass cloth on a clean surface and use a plastic spreader to force the adhesive into the fiberglass cloth.
6. Apply fiberglass cloth patch to backside of repair area.
7. Apply additional structural adhesive over surface of fiberglass cloth patch. Allow 20 to 30 minutes cure time at 16 to 27 degrees C (60 to 80 degrees F).
8. Repair the face of the panel as outlined in Level 2 repair.

Level 4 Damage Repair: For severe or multiple damage, replacement of the damaged panel is recommended per Service Manual instructions and panel refinishing according to refinishing procedures outlined in Level 2 Damage Repair.

Flexible Plastic Repair

Level 1 Damage Repair: For correcting paint scratches on Flexible Plastic Panels, refer to Priming/Surfacing section of this bulletin for Flexible Plastic Refinishing Procedures.
Level 2 Damage Repair: Saturn Corporation recommends the following procedure for repairing cosmetic damage, minor scratches and gouges.

1. Clean repair area with mild detergent and water. Follow with grease and wax remover and then wipe dry.
2. Use a 2 or 3 in. #50 grit disc to slightly enlarge the damaged area.
3. Using a D-A sander fitted with a #180 grit disc, remove the paint film from the surrounding area that is to be filled. Repair material should not overlap the painted surface.
4. Apply a double wet coat of Polyolefin Adhesion Promoter to entire exposed area.
5. Mix Flexible Parts Repair Material according to manufacturer's instructions and apply to the repair area with a plastic spreader. Build the material slightly higher than the undamaged surface. Allow repair material to cure 20 to 30 minutes at 16 to 27 degrees C (60 to 80 degrees F).
6. When the material is cured, shape repair material with a curved body file. Sand with grade 180A grade disc followed by grade 240A disc.
7. For remaining low areas or pin holes, apply Polyolefin Adhesion Promoter, then mix and spread additional repair material as noted in step #5.
8. Once the repair area is sanded and ready for surfacing, an additional application of Polyolefin Adhesion Promoter is required followed by a double wet coat of Glasurit Glassohyd Sealer over the repair area. Allow the sealer to air dry for 1-2 hours at 16 to 27 degrees C (60 to 80 degrees F), or bake at 61 degrees C (140 degrees F) for 30 minutes. Lightly scuff sand with grade 320A Stikit gold disc. Wipe with a dry, clean cloth.
9. Apply primer surfacer with flex as outlined in Flexible Parts Refinishing and block sand.

Level 3 Damage Repair: The following procedure is recommended for repairing small cracks or punctures.

1. Clean the backside of repair area with mild detergent and water. Follow with grease and wax remover and then wipe dry.
2. Use body tape and a clamp (if necessary) to secure the piece on the face side.
3. Sand backside of the damaged area with a #50 grit disc and scuff the surrounding area with a #180 grit abrasive.
4. Apply a double wet coat of Polyolefin Adhesion Promoter to prepared area of backside.
5. Cut a piece of cloth large enough to overlap the damaged area by 38mm or (1-1/2 in.).
6. Thoroughly mix an adequate amount of Flexible Parts Repair Material and apply a layer around the damaged area approximately the size of the fiberglass cloth.
7. Lay the fiberglass cloth on a clean surface and use a plastic spreader to force the repair material into the weave of the cloth.
8. Apply the fiberglass cloth to the backside of the repair area.
9. Apply additional adhesive over surface of fiberglass cloth patch.
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 under Level 2 Damage.

Level 4 Damage Repair: For severe and multiple damage, replacement of damaged components is recommended per Service Manual instructions. For panel refinishing Saturn recommends Flexible Plastic Refinishing procedures outlined under the Priming/Surfacing section.

Priming/Surfacing

Rigid Plastic or Steel

1. Wash damaged panel and surrounding areas with detergent and water. Rinse thoroughly and let dry.
2. Clean panel with a wax and grease removing solvent.
3. Repair all damaged areas following the repair information provided in this document.
4. Sand entire panel with 240 grit sandpaper.
5. Clean all sanded areas with R-M 901 Pre-Paint Cleaner or a suitable equivalent to remove sanding residue.
6. Use an air gun to remove all dirt from cracks and surface of the vehicle.
7. Apply a light coat of DE15 Diamond Adhesion Promoter over all bare metal areas. Use 379-448 kPa (55-65 psi) of air pressure at the gun.
8. Allow 15-20 minutes of drying time before applying primer surfacer.
9. Apply two or three medium wet coats of DP20 Diamond Prime or an equivalent 2-part primer surfacer.
10. Apply a light coat over the primer. Overreduced (150% to 200%) conventional primer surfacers will work well as a guide coat.
11. Allow the 2-part primer to dry for 1 1/4 hours (under normal conditions) before sanding. Wet sand with a 400 grit or finer sandpaper. Dry sand using a 320 or finer sandpaper. Use the guide coat to indicate imperfections that need to be sanded out.

Flexible Plastic Parts

1. Wash the damaged panel and surrounding area with mild detergent and water. Rinse thoroughly and allow to dry.
2. Clean panel with R-M 900 Pre-Kleano or a suitable equivalent.
3. Repair all damaged areas. Refer to the appropriate repair section for proper procedure.
4. Sand entire panel with 240 grit sandpaper.
5. Clean all sanded areas with R-M 901 Pre-Paint Cleaner or a suitable equivalent to remove sanding residue.
6. Use an air gun to remove dirt from cracks and surface of the vehicle.
7. Apply one coat of Polyolefin Adhesion Promoter or a suitable equivalent over all bare plastic areas.
8. Allow adhesion promoter to dry 10 to 15 minutes before applying primer surfacer.
9. Mix DP20 Diamond Prime or a suitable equivalent with DF25 Diamond Flex or a suitable equivalent. Before mixing refer to mixing instructions for the specific paint system being used. In general, mix three parts of primer with one part flexible additive, one part primer hardener and one part primer reducer.
10. Apply two or three medium wet coats of primer surfacer.

Basecoat/Clearcoat Refinishing

Rigid Plastic or Steel Parts
According to Saturn, the refinishing process for steel and rigid plastic is the same. Flexible additives are not required for use on Acrylonitrite/Butadine Styrene and Polycarbonate (ABS & PC) or Polyamide and Polyphene Ether (PA & PPE) materials as long as OEM equivalent topcoats are used.
Flexible Plastic Parts
All exterior flexible plastic parts used on Saturn automobiles are a Thermoplastic Olefin (TPO) compound. Refinishing requires the use of flexible additives in the primer surfacer and clear coat. Flex additives need not be used in the basecoat. Additionally, a Polyolefin Adhesion Promoter must be used over all bare plastic surfaces.
Note: Although this document lists products of certain manufacturers, it is done for illustration purposes only. Various paint and repair systems are available from several manufacturers. When choosing a system, pay close attention to the different system components and application procedures. Regardless of the products chosen for repair, it is important that you stay with one manufacturer's paint system. This will ensure proper compatibility during the refinishing process.

Replacement Parts Refinishing

Rigid Plastic and Steel
Original Steel and Rigid Plastic replacement parts come with a high-bake factory primer. For the proper adhesion of color coats,the following refinishing steps are necessary.

1. Clean paint with a wax and grease removing solvent such as Prep-Sol, Pre-Kleano, Sher-Will-Clean, Acryli-Clean or a suitable equivalent.
2. Scuff-sand panel (wet or dry) with a #400 sandpaper. Avoid sanding through the primer.
3. If factory primer was sanded through on a metal part, apply metal conditioner to exposed bare metal (as per product instructions).
4. Apply urethane primer-surfacer to entire part and allow to dry thoroughly before sanding. Follow product instructions for information on adequate drying time.
5. Sand primer-surfacer (wet or dry) using a #400 sandpaper.
6. Apply necessary color coats to part.

Flexible Plastic
Flexible plastic replacement parts come primed from the factory. For proper adhesion of color coats, follow refinishing steps detailed under Priming/Surfacing section.

Refinishing for Interior Applications

For interior paint system applications, Saturn recommends that all Ploycarbonate (PC) and Acrylonitrite/Butadine/Styrene (ABS) be treated the same for refinishing purposes. PC and ABS can be painted directly and require no primer to bond the lacquer to the plastic. However, the plastic must first be cleaned thoroughly before painting. Poly Vinyl Chloride (PVC) must be first primed before painting. Saturn does not recommend painting soft PVC. Solvents used in the painting process can distort the foam used as padding beneath the vinyl covering. Refer to the Saturn Service Manual for more information on correct panel treatment and repair. It is important to note that Saturn does not recommend the use of lacquer on the vehicle exterior door panels.

Corrosion Repairs

According to Saturn, DP90 Epoxy Primer mixed in a 1:1 ratio with DP401 Catalyst, produces a corrosion-resistant epoxy primer. Other suitable combinations of products are available from other paint manufacturers. Saturn recommends the following for surface preparation:

1. AMCHEM Bonderite 68 (or a suitable product that produces a zinc phosphate coating on steel surfaces) must be applied to ALL areas of bare metal exceeding 25mm (1inch) in diameter.
2. For areas smaller than 25mm (1in.) in diameter, wire brush and wipe the surface which has been welded or repaired, so as to remove any oxidation or loose particles before application of DP90/DP401 epoxy primer.

Epoxy Primer and Catalyst Preparation:
Follow manufacturer's directions when mixing epoxy primer and epoxy primer catalyst. Apply one to two full wet coats, using a spray gun on all visible surfaces, or paint brush-on covered or non-visible surfaces. Allow to air dry for one hour at 21-30 degrees C (70-85 degrees F), or force dry for 30 minutes at 61 degrees C (140 degrees F).
Basecoat/Clear Coat Spot Repair
Saturn recommends the following procedure for performing spot repairs on original basecoat/clearcoat.

1. Wash the entire panel and surrounding area with water and a mild detergent. Rinse thoroughly and let dry.
2. Clean the entire panel with R-M 900 Pre-Kleano or a suitable equivalent.
3. Prepare all damaged and bare metal surfaces (Refer to previous section on repair or undercoating).
4. Sand the repair area. (Wet sand using a 400 grit or finer paper or dry sand using a 320 grit or finer paper).
5. Use a fine compound such as R-M 852 White Compound to compound the undamaged area of the panel.
6. Scuff sand the compounded area with a 1200 grit or finer sandpaper.
7. Clean the entire panel with R-M 901 Pre-Paint Cleaner to remove all compound and sanding residue.
8. Use an air gun to remove all dirt from the cracks and surface areas on the panel.
9. Tack the entire panel with a clean tack rag.
10. Mix base coat color. Refer to manufacturer's instructions.
11. Apply the first coat of basecoat color over the repaired area only. Use 206-276 kPa (30-40 psi) of air pressure at the gun. Allow five to ten minutes flash time between each coat of basecoat color.
12. Apply the second coat of basecoat color over the same area as the first and about four to six inches beyond where the second coat ended.
13. Apply the third coat over the same area as the second coat and about four to six inches beyond where the second coat ends. Normally two to three coats are necessary to obtain proper hiding. Do not melt in the dry edge of the basecoat color after finishing the blend, the clearcoat will accomplish this.
14. Allow the final coat of basecoat color to flash for at least 15 minutes, but no longer than 12 hours before applying the clearcoat.
15. Follow product label instructions and mix two component clearcoat.
16. Tack the entire panel with a clean tack rag to remove dry overspray.
17. Apply three or four medium wet coats of clear over the entire panel. Use 379-413 kPa (55-60 psi) of air pressure at the gun. Allow five to ten minutes of flash time between coats.

Basecoat/Clear Coat Panel Repair
Trying to achieve a perfect color match when painting a replacement panel or spraying the edge of a repaired panel may require blending the basecoat into the adjacent panel or panels.

1. First, wash the entire panel and nearby surrounding panels with a mild detergent and water. Rinse thoroughly and let dry.
2. Clean all panels with R-M 900 Pre-Kleano or a suitable equivalent.
3. Prepare all damaged and bare metal areas according to material from previous sections.
4. Wet sand entire repaired panel with 400 grit or finer paper. If dry sanding use 320 grit or finer sand paper.
5. Use a fine compound such as R-M 852 White Compound (or a suitable equivalent) to compound the adjacent panels.
6. Scuff sand compounded areas with 1200 grit or finer sandpaper.
7. Clean all panels with R-M 901 pre-Paint Cleaner to remove the sanding residue.
8. Use air gun to remove all dirt from the cracks and surfaces of panels.
9. Tack all panels with a clean tack rag.
10. Mix DS30 Diamond Transparent Selaer (or a suitable equivalent) according to label instructions.
11. Apply one or two medium wet coats of sealer using 345-413 kPa (50-60 psi) of air pressure at the gun. Allow five to ten minutes of flash time between coats of sealer.
12. Allow one hour of flash time between the final sealer coat and the application of the first coat of basecoat color.
13. Tack all panels with a clean tack rag.
14. Follow product label instructions and mix basecoat color.
15. Apply first coat of basecoat color only over the repaired panel using 310-379 kPa (45-55 psi) of air pressure at the gun. Allow five to ten minutes of flash time between each coat of basecoat color.
16. Apply a second coat of basecoat color, overlapping the first coat area by four to six inches.
17. Apply the third coat, overlapping the second coat coverage by four to six inches. Normally two or three coats are necessary to obtain hiding. Do not melt in the dry edge of the basecoat color after finishing the blend, the clearcoat will accomplish this.
18. Allow the basecoat color to flash for at least 15 minutes, but no more than 12 hours before applying the clearcoat.
19. Remove dry overspray from all panels using a clean tack rag.
20. Apply three or four medium wet coats of DC88 Diamond Clear or equivalent over all panels. Use 16-20 kg (35-45 lbs.) of air pressure at the gun. Allow five to ten minutes flash time between coats.

Note: Basecoat/clearcoat refinishing of flexible plastic parts requires the use of a flexible additive in the clearcoat. Otherwise the repair procedure is the same as identified for steel and rigid plastic parts.

Color Coat with Acrylic Urethane Clear CoatThe information provided in this bulletin is for educational purposes only. Although every effort has been made to ensure the accuracy of the information contained in this bulletin, Tech-Cor assumes no responsibility or liability for any repairs performed using information from any publication issued by Tech-Cor.

Any person performing repairs must determine whether any suggested or recommended procedures or repairs are suitable or appropriate for the particular vehicle being repaired. The repairer remains solely responsible for such determination, as well as for the proper completion of the repairs.

Reproduction of this bulletin is not permitted without the written approval of Tech-Cor.

I didnt realize there were so many different types of composite plastic used in the cars, I though it was all one kind. I was always curious as to how one repainted the plastic panels. I will have to file this away for the next tupperware machine