Old timer at the shop swore by Bondo when I first started, said never use fiberglass filler

Guy had 30 years in the trade and told me to stick with Bondo for everything including some pretty deep rust holes on a 2005 F-150 I was patching up. I followed his advice for about two years until a panel I did started cracking in the middle of a Cleveland winter last January. Now I'm wondering if he was just stuck in his ways or if I was doing something wrong. Any of you guys run into a similar situation where someone's old-school advice backfired on you?

2 comments

2 Comments

terryb118d ago

Ever try using a flexible additive with the Bondo?

gibson.mark8d ago

Oh man, yeah! I tried that last summer on a plastic bumper repair and it made a huge difference. The regular Bondo cracked right out of the gate on the first flex test, but with the flexible additive it held up no problem. Made the whole sanding process a little gummed up though, so I had to watch my speed or it would ball up on me.