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How to Recondition a Bumper Cover
Everyday, bumper recyclers recondition bumper covers and then sell the reconditioned bumper covers to body shops. Buying reconditioned OEM bumper covers from a bumper recycler saves money for the insurance company and the customer. And, because it is a reconditioned OEM bumper cover, you can be confident that the bumper cover will fit. Aftermarket bumper covers often do not fit well.
This bumper was damaged in a common, real-world accident; a dog ran out in front of it. (Don't worry - the dog is fine, and it has learned its lesson and does not chase cars anymore!) You can see that this type of damage is repairable, and the repaired bumper is much less expensive than a new OEM bumper.
This video shows how to weld the broken pieces back together, remove dents and high spots, and repair a crack in the fog light area.
Check out our Welding Rod List to pick out the perfect welding rod for your project. If you aren't sure which rod you need, visit our Plastic Identification page.
Always wear proper safety gear while working!
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Products Used:
`Note: This is a list of the Polyvance products that can be used to make this repair. This list does not include sanders, grinders, or other common tools you will need. If you have any questions, please don't hesitate to call technical support at 800-633-3047.
- Aluminum Body Tape (several options available)
- 1000 Super Prep Plastic Cleaner (several options available) OR 1001-4 EcoPrep Plastic Cleaner
- Plastic Magic Adhesion Promoter (several options available)
- Nitrogen Plastic Welder (several options available)
- Polypropylene Welding Rod (several sizes/colors available).
Note: We used polypropylene here because of the identification symbol. Choose the rod that matches the plastic you need for your repair. - 6125 Tapered Burr
- Waterborne Primer Surfacer (several options available)
Video Notes:
- Super Clean Plastic Cleaner has been renamed Super Prep Plastic Cleaner.
- English Closed Captions have been provided for this video. Click on the CC button to turn them on or off.
- The length of this video is in no way representative of the actual time required to perform a complete repair and therefore should not be used for estimating purposes.
English Transcript:
This Ford Fusion hit a dog and the bumper was damaged. A replacement bumper cover is over four hundred and fifty dollars. A bumper cover that is damaged this badly would normally be replaced. After all, how can this much damage possibly be repaired? This video will show all the steps necessary to get this bumper ready to paint.
First, you will carefully align the edge of the crack and temporarily hold it into place with self-locking pliers. This will keep it from moving around while you apply the aluminum tape. Use six mil aluminum tape because it is very stiff. The tape you get at the hardware store is too thin; it bends and stretches easily and makes it more difficult to keep the plastic in alignment. After applying the tape, use a spreader to remove the air from beneath the tape. Removing the air gives a better bond to the bumper. Once everything is taped up, turn the bumper over and use Super Clean Plastic Cleaner to clean the damaged area.
The repair will be weakest at the edge. Any bending and flexing of the bumper will more than likely break in the same spot. To prevent this from happening, you will want to reinforce the edge with a polypropylene strip. You get a better weld if you can remove any of the oxidized plastic that is on the surface and expose new plastic. Use the edge of a Roloc disc to grind away a small layer of oxidized plastic. You will be using an eighth inch diameter welding rod to weld the crack. Use a die grinder with a tapered burr to grind a v-groove along the crack line. Grinding the v-groove will help remove some of the existing plastic and remove any oxidized plastic.
Nitrogen acts like a shielding gas when you are welding. You will get much stronger welds using nitrogen than you would if you use air. Soften the tip of the welding rod and the base material until they melt together. Aim the flow of air slightly in front of where the rod meets the base material. You want to make sure that you soften the base material in front of the rod so the rod will easily melt together with the base material. Apply gentle downward pressure on the rod so that it melts into the base material, not just on top of the base material. In places where you have to cross another weld, go ahead and weld over the previous weld. Don't try to start the weld against the previous weld, as it creates a weak spot. Continue welding the entire length of the crack. When you reach the end, give the welding rod a twist to break it off.
Here is the part where we strengthen the edge by welding a wide strip of plastic across the surface. While the plastic is still soft, use the airless welder to smooth down any curled edges. Remove the self-locking pliers, and apply the aluminum tape to the part that has not been welded yet. Prepare the surface just like before by grinding away a thin layer of oxidized plastic. Here we use the edge of a Roloc disc to expose new plastic. Continue welding all the way to the end along the crack line. When you reach the end, give the rod a twist to break it off. While the plastic is still soft, use the airless plastic welder to flatten out the welding rod. Just like the first edge, weld a wide strip of polypropylene along the edge for reinforcement.
After the weld has cooled off, you can peel the tape from the front side. Then use a die grinder with a pointed cutting burr to grind a v-groove along the crack line. Grinding the v-groove can cause some fuzz to develop, but you can scrape it away with a putty knife. And use the eight inch diameter polypropylene welding rod for the weld. When the weld is complete, use the airless welder to melt in the edges and scrape away excess plastic. That way you won't have to do as much grinding later.
In many collisions, the bumper gets dented and scratched. You can remove most of these dents by softening the plastic with a heat gun. Heat the plastic slowly so that the heat penetrates through the thickness of the plastic. When the backside of the bumper is too hot to touch, you are ready to start shaping the plastic. Use some wooden dowels to shape the plastic. Use 36 grit sandpaper on a DA sander and sand down the weld until it is flush with the surrounding surface. Also, sand the paint away from the damaged area. This will help you identify the low spots like these. Heat up the plastic again and push out the dents. You won't have to use as much filler later if you can get the dents out now. Continue sanding away with 36 grit. In some places like this grille area, you won't have to sand it with a DA sander. Use a Roloc disc to grind away the excess plastic. The 36 grit sandpaper makes the surface very rough and would require a lot of filler to get smooth. To get it smoother, switch to 80 grit sandpaper, and sand until most of the 36 grit sand scratches are gone. The filler that you apply will stick fine to 80 grit sand scratches.
While repairing, you may find more damage than you originally thought, like this crack in the fog light area. This area can be sanded, but it is very tedious to get into all the corners. It is quicker just to put the bumper cover in a blast cabinet and blast the paint away from the damaged area.
Apply aluminum tape over the crack on the front side. Most of the repair will be done from the back side and hopefully the front won't need to be welded at all. Use a Roloc disc to grind away the oxidized plastic on the surface. And use the eighth inch polypropylene rod to weld the crack. Because of where the crack is, appearance isn't important. So to strengthen the repair even more, melt several passes on top of each other. The airless plastic welder is too wide to fit into this area, so use the tip of the nitrogen welder to melt in the edges of the weld.
Allow the plastic to cool and re-solidify before working on the front side. Remove the aluminum tape from the front side and sand away any paint around the damaged area. The area behind the crack is solid plastic from the several layers of welding rod that were applied to the backside. So just try to shape the plastic on the front side with the airless plastic welder and don't bother adding more plastic. When the plastic cools, fan the plastic to the correct contour.
Now it is time to add filler, but first clean everything with Super Clean Plastic Cleaner and wherever there is exposed plastic, apply Plastic Magic Adhesion Promoter. After mixing a flexible polyester glaze in the can, put a small amount on a mixing board and mix in some of the cream hardener. Apply the flexible polyester glazeto the damaged area with a plastic spreader. Get it as smooth as possible using the spreader. This will save a lot of time later when it is time to sand the filler. With a little bit of practice, you can get the filler really smooth with a spreader and really cut down on the sanding time.
After the filler cures, start sanding using 80 grit sandpaper on a DA sander. 80 grit will knock down the high spots quickly. Occasionally, check the contour to see where additional sanding may be required. When the contour is right, switch to 180 grit sandpaper. The primer will fill 180 grit sand scratches, but not 80 grit. Blow the dust away and check to see if you missed anything. Some spots will need to be sanded by hand.
Apply the first coat of primer surfacer. This coat will fill the sand scratches and will be sanded smooth, so you don't have to worry too much about laying down a perfect finish. Sand the primer smooth with 320 grit sandpaper and apply a final finishing coat of primer. Try to get this coat as smooth as possible, because when this coat dries, the bumper cover will be the product you deliver to the body shop and it needs to look really good. When the primer dries, wrap the bumper in bumper wrap to protect the finish during delivery. The body shop will appreciate the wrap, too.