Plastic repair GURUS since 1981
Bumper Grille Bar Repair with the Nitrogen Welding System
Grille Bar Repair Video
Many bumper covers are thrown away and replaced simply because the grille bars are broken. You don’t need to replace the bumper cover when the grille bar can easily be repaired using Polyvance’s Nitrogen Welding System.
Look at these broken grille bars to see what I am talking about. This is pretty common on Honda bumper covers, but it happens to others as well.
Use a tapered burr on a die grinder to grind a V-groove into the back of the grille bar and in the plastic where the grille bar connects to the bumper cover.
Also, grind a "T" in the plastic where the grille bar attatches to the bumper cover.
The edge of a Roloc disk may be used to make the groove if you don’t have a tapered burr.
Hold the grille bar in place with tape, if necessary, until the repair is complete. This bumper cover is polypropylene so we are using a polypropylene rod with the Nitrogen Welding System. Melt the rod into the groove that you just made and be sure to melt the rod AND the existing plastic together.
Weld into the "T" that you created earlier. This strengthens the grille bar considerably. After you melt in all the plastic necessary for the repair, give the rod a twist to break it off. Now, switch the welder from Nitrogen to air to avoid wasting your nitrogen.
While the plastic is still hot, use the airless plastic welder to melt in the edges and shape the plastic.
Either wait for the plastic to cool or, speed up the cooling with compressed air, like we did here.
Some of the plastic may have curled around the grille bar during the repair. Use the airless plastic welder to shape the plastic from the front side.