Problems Painting Brand New Bumper Cover

General Discussion. Make yourself at home...read, ask and answer!



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Fri Feb 20, 2009 3:41 pm
JCClark and PaintDevil;

Thanks for the advice, I'll be following your suggestions when I paint next but I think I'll wait until the weather gets into the 50s at least.

I understand it is difficult to match a 3 stage and it probably won't be "perfect" when done but I expect myself to be able to perform "good enough".

I plan to use a refinished section of the the old bumper cover to try and match up the midcoat.

Thanks again

jmd_forest



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Fri Feb 20, 2009 8:41 pm
PaintDevil,

When you mentioned earlier to scuff it up with a gray pad and "ajax", are you talking about Ajax scouring powder, the kind you get at the grocery store? If so (or if not, what are you refering to?) is this a wet or dry scuffing procedure.

Thanks for any info you might be able to provide.

jmd_forest



Fully Engaged
Posts: 162
Joined: Wed Mar 12, 2008 1:46 am
Location: Philadelphia PA
PostPosted: Fri Feb 20, 2009 10:42 pm
Yes thats the ajax I am talking about or Comet. The purpose of it is that it cleans the parts of any type of mold, dirt, etc etc that could create fisheyes or poor adhesion because of dirt...

Grey scuff pad is the perfect "grit for adhesion" combined with ajax or comet it works wonders. I think ajax works better then any wax/greese remover I have ever used and its cheap .89 a can...

Defidendly do a test panel, tri-stage paint is a real painnn in the butt.

I painted a body kit for a new Lamborghini Gallardo, it was a tri-stage orange color, real nightmare!



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Sun Feb 22, 2009 12:39 pm
Well....The bumper cover has been stripped, 400 grit wet sanded with detergent, wet sanded 400 with clean water, and "Cometted" with water using a grey skuffing pad.

I'm pretty sure I'm down to raw plastic. My biggest concern now is that after the Comet and Skuffing pad and clean water, the clean water beads up pretty fast (couple seconds) rather than sheening. The cover does dry to a nice flat looking finish, no shiny spots

Is there anything I'm missing? I really don't want to apply the paint and wind up crazed again.

This thing was not contaminated, at least by me. I pulled it straight out of the shipping bag, wet sanded, dried, and shot the Bulldog before the first paint attempt.

jmd_forest



Fully Engaged
Posts: 162
Joined: Wed Mar 12, 2008 1:46 am
Location: Philadelphia PA
PostPosted: Sun Feb 22, 2009 3:48 pm
If it dries to a nice matte chalkboard looking finish your in good shape. The comet and ajax works wonders to decontaminate any surface...

You should defidently take some pictures that way if there is a problem its easier for us to help you out...

Make sure when you use the bulldog just apply it in light misting coats, the stuff is no joke and works wonders. When you apply it heavy it can turn into a real nightmare. I've had it where I sprayed the bulldog too heavy and waited not enough time, when you apply the primer it creates an avalanche effect and primer cracks and starts to slide, real wierd effect....

Apply your bulldog...OVERWAIT the recommended time, shoot your base/mid/clear...Try and paint in cleanest area possiblem that bulldog is a dust trap



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Sun Feb 22, 2009 4:48 pm
Good to know about the Bulldog mist coating...After reading that I suspect that may have been my original problem, too much Bulldog.

Yes, it has a nice mat finish when dry.

I'll mist coat and wait 30 minutes before hitting it with the 2K primer mixed with 10% Bulldog.

I'm hoping tomorrow is at least in the 40s so I can warm up the garage to the 50s

jmd_forest



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Thu Feb 26, 2009 2:05 pm
It warmed up to the 50's today so I thought it would be OK to primer the bumper cover. I warmed up the garage a touch and shut off the heater. Cleaned the gun real good and shot a light wet coat of Bulldog. It went on just a hint wet wet and clear. Let if flash for 1/2 hour while mixing up the 2k primer. Added about 10% Bulldog into the 2k and just a capfull of urethane reducer to thin it out a touch since it was coming up a little dry on my test panel.

I decided to forgo the epoxy coat since it is just one more thing I could screw up and I'm too familiar with that already.

Shot 1 light 2K primer coat, let it flash for 15 minutes and them 2 "light medium" coats with about 15 minutes of flash each. The bumper cover came out beautiful and smooth, no crazing of any kind.

Letting it dry for the rest of the day (about 8 hours) and will 400 grit wet sand it tonight in prep for real paint tomorrow.

Its supposed to be in the high 50s here tomorrow and I'm hoping to shoot the 3 stage on the 4 panels (hood, 2 fenders, and bumper cover) so I can finally get this car finished.

Thanks for the help gentlemen



Fully Engaged
Posts: 162
Joined: Wed Mar 12, 2008 1:46 am
Location: Philadelphia PA
PostPosted: Thu Feb 26, 2009 6:34 pm
Take some pics for us! Good luck, remember take your time and dont do something stupid...



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Thu Feb 26, 2009 8:20 pm
I'll post pictures if its good and run away crying like a little girl if its bad (or beat my spray gun into a lump).

So much work and time when things get screwed up when your an amateur.

jmd_forest



Settled In
Posts: 19
Joined: Thu Feb 19, 2009 11:21 am
PostPosted: Fri Feb 27, 2009 12:53 pm
Well.....All went well except for the picture below. I have NO idea what went wrong

The "crack" happened after first pearl coat. This picture taken before clear coat. I figured I'd just push through and then sand out and patch up the spot after everything cures.

Image


Anyone have any idea what is going on. it is the only flaw in the entire job. Believe me when I say there was no contamination.

jmd_forest
PreviousNext

Return to Body and Paint

Who is online

Users browsing this forum: Google [Bot] and 126 guests