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-   -   Endura bumper paint CRACKS (https://forums.maxperformanceinc.com/forums/showthread.php?t=737389)

grrrrregg!!! 09-18-2013 08:50 PM

Endura bumper paint CRACKS
 
3 Attachment(s)
The service bulletin and the other Endura bumper fixes on this site are great info and thanks to all that posted. I'm just curious about these cracks on my bumper. Are they the norm or is something else happening. They are almost perfectly strait and evenly spread out. It almost looks like a bad clear bra job, done in pieces. The pictures are of different cracks and the third pic shows 3 cracks and how they are spread out. It is on both sides. I'll be fixing this in a few months and want to make sure i'm not dealing with another problem. pics below.

thanks, Gregg

andyg 09-18-2013 10:58 PM

My bumper had the same thing happen. I need to study all the repair info on here this time around to help avoid that again. The bumper really is a pain in the butt.

GTOnly70 09-19-2013 11:04 AM

Great article on endura resto: http://www.goatsgarage.com/bumpfrm1.html

gtohurstjudge 09-19-2013 12:28 PM

From 1972 to 1998 I probably repainted my front bumper 7 or 8 times
because of paint cracking. I tried every technique and every type of flex additive
I could find. Whenever I painted my bumper I would get a small crack in one of the
outside corners the first time I drove the car around the block. Being a convertible,
the bumper flexes more on my car than on a hardtop. Finally in 1998 I found a painter who said he could paint my bumper and it wouldn't crack. I laughed in his face, telling him to
go ahead and strip it and paint it but I knew it would crack the first time I drove the car.
He painted it and fifteen years later it has one teeny tiny crack about an eighth of an inch
long in one corner that happened twelve years after it was painted when I was driving
around hairpin curves at 70 miles per hour while filming a segment for Musclecar TV. I don't
know the name of the flex product but I do know it was made in Europe.

68gtoMN 09-19-2013 03:21 PM

See posts by PaulatFast - paul Freese. He's been repairing/repainting these for YEARS with tremendous success...

paint guy 09-19-2013 08:24 PM

flex additive
 
Quote:

Originally Posted by gtohurstjudge (Post 5024572)
From 1972 to 1998 I probably repainted my front bumper 7 or 8 times
because of paint cracking. I tried every technique and every type of flex additive
I could find. Whenever I painted my bumper I would get a small crack in one of the
outside corners the first time I drove the car around the block. Being a convertible,
the bumper flexes more on my car than on a hardtop. Finally in 1998 I found a painter who said he could paint my bumper and it wouldn't crack. I laughed in his face, telling him to
go ahead and strip it and paint it but I knew it would crack the first time I drove the car.
He painted it and fifteen years later it has one teeny tiny crack about an eighth of an inch
long in one corner that happened twelve years after it was painted when I was driving
around hairpin curves at 70 miles per hour while filming a segment for Musclecar TV. I don't
know the name of the flex product but I do know it was made in Europe.

Your painter knew what he was doing. Most flex additives in use today (for collision repair) are volatile, and as such, will evaporate or migrate out of the paint film after a period of time. They will work for collision repair as bumpers and such are painted, then installed within a couple of days, so the paint film doesn't really have to stay flexible for any great length of time. Your painter probably used some type of flexible additive that became a permanent part of the film (probably polyester).

Verdoro 68 09-20-2013 12:39 AM

I'd definitely call that typical cracking. Do you know how the bumper was prepped last time it was painted?

Here's what mine looked like stripped down. When it was painted in '92 they used filler primer on the bumper and didn't take long to crack. You can see how it's in the rubber and came up through the paint.

http://forums.maxperformanceinc.com/...1&d=1329021548

http://forums.maxperformanceinc.com/...1&d=1329021342

Like the other's said, follow Paul's procedure:
http://forums.maxperformanceinc.com/...71&postcount=2

I didn't sandblast mine, but I took it down to bare rubber with 80 grit, v'd out the big cracks and filled them with 3M epoxy. The shop did the rest of the smoothing and primed it with epoxy primer before the color and clear. So far so good, but it's only been about a year and a half.

grrrrregg!!! 09-20-2013 08:19 PM

Quote:

Originally Posted by Verdoro 68 (Post 5025048)
I'd definitely call that typical cracking. Do you know how the bumper was prepped last time it was painted?

Here's what mine looked like stripped down. When it was painted in '92 they used filler primer on the bumper and didn't take long to crack. You can see how it's in the rubber and came up through the paint.

http://forums.maxperformanceinc.com/...1&d=1329021548

http://forums.maxperformanceinc.com/...1&d=1329021342

Like the other's said, follow Paul's procedure:
http://forums.maxperformanceinc.com/...71&postcount=2

I didn't sandblast mine, but I took it down to bare rubber with 80 grit, v'd out the big cracks and filled them with 3M epoxy. The shop did the rest of the smoothing and primed it with epoxy primer before the color and clear. So far so good, but it's only been about a year and a half.

Not sure how my bumper was prepped. Thanks for the pics of your stripped bumper, those cracks are consistant with what I have going on with my bumper. I will check out those links posted, some good info.

Thanks all for responding


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