onesmartidiot

I am being told there is a special preperation/ method to painting plastics which will prevent spiderwebbing and peeling down the road. I am a new painter and am learning the basics by spraying por-15 on my camaro and tbird. Just seeing if this is true or if it all paints the same.

Also, my nose has faint spiderwebs in it, it was probably bumped into something before i bought it. And my front lip was "cheese grated" while loading onto a trailer, what will I need to smooth these out/repair before paint?

87IROC-DAN61

Hello onesmartidiot!!

Look into stuff called "flexagent" (sp) it's supposed to let the paint on the plastic have some flexability before it cracks from flexing!!

I don't know how true this is, but that's what I've heard, sounds good!!!



As for your other questions..............I'm not a painter!!

haps

iTrader: (4)

Save your money and don't buy the flex agent. Sand the webs completely out and prime with a high quality automotive primer. I've never been able to keep the webs from returning. Sometimes they do....sometimes they don't.

puma1552

iTrader: (1)

Maybe you should try the flex agent then?

I have heard that if the spiderwebbing is severe, it's probably damaged the urethane bumper, in which case the plastic itself would need to be replaced.

I don't know if there's any truth to this or not.

I've got some spidercracking on my nose and a body shop told me they would recommend a new bumper cover even though the bumper cover appears to have no issues, just cracked paint on it.

haps

iTrader: (4)

I have off and on over the years. I've never been able to attribute any sure fixes to the flex agent. I haven't used it for a while and honestly don't know the difference. I've always suggested replacing the urethane when it's spider cracked, but sometimes that isn't the most cost effective solution.

Gumby

Going on 7 years now and no spiders or cracks, using black enamel paint.
Didn't use any flex agents, painted the whole car end to end in one shot.

metal, plastic, rubber.........

trocustoms

iTrader: (1)

There is spider cracks in paint which can be sanded out, primed and painted successfully. There is also cracking do to the covers being damaged from being hit.These can be sanded down and repainted but usually come back.

As for flex agent, its primary use is when painting a flexible part such as a bumper cover, it is added in the base coat and the clear coat. This allows the installer to be able to move the cover around when installing it. The covers need to be flexed to go over the bumper reinforcements etc. The flex agent has a small window of flexibility, then it cures out. With that being said i still use it on every flexible part i paint for myself. It cant hurt!!!!!!!

3rdgenfever

any flex agent i have used we add to the primer/surfacer or the sealer. If and when you sand those spiderwebs down (which is in the paint not the bumper most times) you will get down to the raw plastic. You will need to coat those areas with a adhesion promoter to keep the top coats from lifting and causing issues down the road. The sand paper you should use to get the cracks/webs out should be somewhere around 180 grit. work your way up to 320 or 400 and the primer and sealer should cover/fill those scratches no prob. there is even some stuff called fill primer which you will need to spray out a 2.0 tip gun or fill them with some kind of filler.... bondo/putty whatever if they are deep. sand that down and begin the paint process.

vistageek92

iTrader: (2)

I just painted my car this week. There isn't much you can do about that spider cracking, at least preventing it. I sanded all my rubber parts to the bare rubber to get rid of the previous cracks. Then sprayed them with filler primer and sanded that down with 320 grit. Then 3:1 auto primer then my coats of base then clear. Can't even tell there waere bad cracks in them.

As for preventing them, I would say the best thing is proper prep before paint like I explained above.

Gumby

Which means it doesn't do a thing to prevent them in the long run.
Just a short window so you can flex parts around beyond normal and not fubar it.

Which would mean unless your gonna handle parts like that, the flex agent is a waste of money. Which may be well spent on the can't hurt excuess, long as you have it to spend.

FryeDaddy

iTrader: (1)

you spray paint the whole car you mean? (I just brought 3 cans of automotive black paint gonna spray on hood to clear up the marks; scratches)

Gumby

Um no, but was only $40 for a gallon.

look up paintforcars on eBay or their website
http://www.paintforcars.com/customer_testimonials.html

Head to any car show with original hotrods and all you will find is enamel paint jobs, which some you could walk right into its so deep black.
New fancy stuff just cost more when you talk black.

Maverick H1L

iTrader: (8)

Don't know about the flex agent. I've used cheap crap paint (RustOleum on both of my spidercracked bumper covers and even though the paint flakes off everywhere else, I'm having a ball removing it from the bumper covers (150 grit right now on a DA and it's still taking forever and a day to come off).

Don't know how they got there, but my front cover has some really deep gouges in it from the spidercracking (I would assume as it's in line with it), and I'm working on sanding those flat as well.

One question: Can I use any kind of body filler on the front cover or do I have to find something special? The pass side of the center part of the nose (between the center line and where the dip is for the park lights and trim) has a recess in it, almost what could be considered a dent.

FueledSoul

iTrader: (18)

I used a flex agent in my primmer/seal coat a few years back and It was recommended... my parts ( front bumper/ front GFX and rear bumper) have cracked since then (the top side of my fiberglass hood did not however and seems to be holding up fine i plan to hand said most of that coat down and re-spray. instead of sanding the bumpers and GFX by hand again im going to have them soda blasted... When i prep the under side of my fiberglass hood i ask a few people about adding a flex agent, One guy at the place i buy paint said: No you don't need one. Why? because today's primers, paints etc are much more advanced they don't even use flex in factory paints anymore as far as im aware... So im painting a fiberglass hood it flex's alot you can guarantee me that im not going to have problems? Yes apsolotoy wont have any problems...