Have a look at this vid from Polyvance be sure to turn the volume down at the start of the vid. . Yes I know, odd name, they used to be called USC. I have their airless plastic welder kit and it works great on the 2 bumpers I've fixed.


https://www.youtube.com/watch?v=_x8qtvG-Y8U

https://www.youtube.com/user/urethanesupply/videos?disable_polymer=1