Painting Plastic/Polyurethane Panels - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Body - Exterior
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 08-06-2006, 01:08 PM
bigbrowndog's Avatar
Registered User
 

Last journal entry: Found some headlamps
Last photo:
Join Date: May 2004
Location: Rocky Mountains
Posts: 9
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Painting Plastic/Polyurethane Panels

I ordered some ground effects and new fenders for my wife's 96 Camaro convertible (my son took it into a ditch and it tore it up pretty good). I have the base coat, clear coat, and flex additive. What I am wondering is if I have to primer the plastic? Panels say to sand with 800 grit or finer, and then to follow paint application instructions.

I am thinking that if the plastic is clean, it may bond properly. I am concerned that the primer will crack and flake on the panels that flex, so I should I go without primer?...........

Thanks for the help.

Ty

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 08-06-2006, 09:14 PM
MARTINSR's Avatar
Brian Martin,Freelance adviser
 
Last photo:
Join Date: Jun 2004
Location: San francisco bay area
Age: 55
Posts: 13,095
Wiki Edits: 0

Thanks: 1,279
Thanked 1,118 Times in 994 Posts
You do not want to just "prime" it. If you go to the store you got your paint at they will have a "refinishing guide" for plastic parts which will include the manufacturer of your paints adhesion promotor for plastic parts. You could follow that guide or you could get an aftermarket adhesion promotor like SEM or Bulldog and follow their instructions. PPG has a great adhesion promotor by the way.

And you do NOT need any kind of flex additive with most paints and clears these days. That is a product from the dark ages.

Brian
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 08-07-2006, 07:17 AM
crashtech's Avatar
Technician
 
Last wiki edit: Epoxy primer
Join Date: May 2005
Location: Idaho
Posts: 701
Wiki Edits: 17

Thanks: 0
Thanked 0 Times in 0 Posts
I like to cut a bit of the plastic from an inconspicuous area and put it into a cup of water. Then use the saying:

"If it's a floater, it needs promoter"

IF the parts are polyurethane, they actually do not need adhesion promoter. If they are polypropylene or thermoplasic olefin, they do! So ID'ing the plastic is important, as is following the paint mfr's recommendations to the letter.

Also, if you are given the option to put some hardener in the base, DO IT! That will improve the strength, flexibility, and adhesion of the base, which is usually the weakest link in the system, especially with flexy parts.

P.S. Make sure the sliver of plastic does not have any air bubbles stuck to it, they may give a false positive on your test!

P.P.S. Lots of plastic parts come primed these days. If so, as long as you don't sand through the primer you are good to go. In these cases I use a gray scotch pad and some prep paste with water to thoroughly scuff the primer without breaking through...
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 08-08-2006, 08:31 AM
Registered User
 
Join Date: Mar 2005
Location: Florida
Posts: 146
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
We paint plastic bumpers everyday at our shop. One thing that you DONT want to do is use wax and grease remover. We don't use primer on the plastic either. We've had to many problems in the past with it. I wet sand with 1000 grit, wash with straight water unless there are greasy spots, then I add a little bit of soap. Apply the basecoat and then clear. 90% of the time we don't use flex additive.

Good luck
Corey
Reply With Quote Quick reply to this message

Recent Body - Exterior posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Painting New Fiberglass body panels jchiesa Body - Exterior 6 04-20-2009 01:14 PM
painting door panels in a 73 nova?? fireforsin Interior 4 05-06-2006 03:49 AM
Door panels stangrodder Interior 4 12-22-2004 10:26 PM
Painting Panels on truck Bluepen Body - Exterior 1 03-05-2003 09:32 AM


All times are GMT -6. The time now is 09:52 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.