Flex Addative

[Mike Dursky]

Is it necessary to add a flex addative(like on rubber bumpers) to the primer and paint when you are spraying plastic side covers for a motorcycle. They do twist some when being removed and installed. I did this back in the mid 80s but not sure it is necessary now

with the new paints. Plan on using PPG basecoat/clearcoat and candy colors.
Thanks
Mike

 

[DDG]

Not really, the flex additive is mainly used for bumpers so when the autobody guys put it on they can bend it to get it on.
Most paint is very flexible anyway.
Ever seen a bad dent? The paint can almost crease before it cracks. That should be proof enough.
Dirt

 

[Mike Dursky]

Very true. Never really thought of it like that .Thanks

 

[rex]

If you're using PPGs urethane bc/cc system it's not necessary.the only 'no-nos' are using the fast 402 hardner in DP epoxies and using the fast clears on urethane bumper covers but down here in the heat it doesn't make a noticable difference.For the covers you're doing there's no worries at all.

 

[Mike Dursky]

It doesn't sound like I will have a problem then.Thanks rex

 

[rex]

Mike,I did forget to say you will need an adhesion promoter on any raw plastic spots if there are any before you prime.Just for trivia about the flexibility back in the 80's and 90's Amerflint urethane was(and still might) made by a place called American Lacquers.If you sprayed their wash primer on a pice of aluminum foil and put Amerflint on it you could litterally ball this into a wad and open it back up with no cracking.After you picked a wrinkle in the foil and played with it some it would finally fail.I've kind of done this with PPGs DBC/Concept clears and they are very pliable.

 

[Mike Dursky]

OK. THanks rex !