Automotive Plastics: Repair of rigid ABS plastic auto dash, perforated metal sheet, radiator grille

Question
How do I join broken ABS plastic pieces back together again so that they are reasonably strong as original part? After joining, how can I fill/repair any seams or irregularities so that the mended part may be painted back to original appearance?

Answer
Dear Robert,The best way to repair a broken dash is welding the torn pieces with a 40 watts soldering iron whose tip must have a spatula-like shape(do this with a grinder).I always suggest to take the dash out, so that welding can also be performed inside and outside the cracks.To get strong joints, insert small pieces of perforated metal sheet with the same tool inside and fill the cracks outside with ABS from a discarded radiator grille (so identified)or a similar dash. Then sand paper with 100 grit until you have a smooth finish. apply a good primer with a cloth,fill the grit scratching with bondo, get a very nice finish... more primer again and paint at 30 p.s.i. If you want stronger joints apply plenty of hot melt glue in the back of cracks. Do this in a well ventilated place as ABS contains Acrylonitrile (vinyl cyanide) a toxic element. Good luck. Octavio.