lead-free body solder crack resistance
I bought some lead-free body solder and decided to do a little practicing on an old fender.Tinned the fender and applied the solder. I found it to be a little easier to work with than standard lead. When i was done i decided to test how well it stuck to the fender.I turned it over and used a body pick to smack the back of the repair area.Where the bumps formed the solder cracked like you would see in your paint if something dimpled it from the inside. I applied some standard 70-30 lead to test the difference. The lead dimpled but did not crack. The lead is alot more flexible.I can bend the lead bar 90 degrees without cracking. The lead-free bar breaks apart when bent to about 50 degrees.My concern is if I use the lead free solder to fill the seams on my car am i going to have problems with it cracking? Some parts of the car that had a skim coat of plastic filler cracked. I plan to solder these areas. Is the lead-free solder going to be any more crack resistant than the previous plastic filler? Do i need to use standard 70-30 solder? Has anyone had cracking issues with lead-free body repairs?