Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Detailing and Interior

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-15-2005, 04:55 PM
Saint's Avatar
Registered User
 
Join Date: Dec 2004
Posts: 119
How do you properly and economically treat a blister

Hi there,
I have a blister on the rear hatch of a 1990 300TE Smoke Silver. Upon close inspection, it looks to be a bit rusty as well.

This blister is about 1 inch in diameter, and is in a REALLY noticable spot. What is the normal procedure short of painting the whole hatch?

Has anyone ever used a spot blaster? I have an aerospace quality spotblaster that has nozzles that allow you to blast a spot as small as 1/2 inch without blasting anymore than that. If I blast off this blister, it will basically feather itself. If I then use MB touch up and primer...would that be about as good as it gets?

Thanks
Attached Thumbnails
How do you properly and economically treat a blister-blist2-2.jpg   How do you properly and economically treat a blister-blist1-1.jpg  
Reply With Quote
  #2  
Old 01-16-2005, 06:49 PM
MB, love..hate..love..
 
Join Date: Apr 2003
Location: NB Canada
Posts: 1,173
I'd say yes, that would be the way to go. I have one of those spot blasters too, and they are perfect for a job like this. The trick will be to minimize the area that you'll need to prime and paint. These little spots get bigger as you progress with the sanding and blending.
I'd use a bit of finishing filler, like Featherfill, if there are severe rust pits after blasting away the rot. If not, just prime, sand, color coat, sand, clearcoat, and final sand to blend. I just know you won't get it to be invisible, but a good job will not stick out like the sore thumb you have now.

Sometimes it's possible to repair and paint only part of a panel, but there needs to be some sort of parting line, like where the sheet metal is creased along the width, in your picture, just above the chrome strip. I don't know about the edges, whether that ridge goes all the way across or peters out toward the outside edges of the hatch.
__________________
1986 560SL
2002 Toyota Camry
1993 Lexus

Last edited by donbryce; 01-17-2005 at 08:05 AM.
Reply With Quote
  #3  
Old 01-17-2005, 03:00 AM
Saint's Avatar
Registered User
 
Join Date: Dec 2004
Posts: 119
thanks....I will get my ducks in a row before starting this. I will post my results...probably about a month from now. Gotta put some time into another car that is having a problem...
Reply With Quote
  #4  
Old 01-17-2005, 07:50 AM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 2,997
I recommend that you have a high end bodyshop that specializes in MB and BMW paint work take a look at your blister. Better to have it professionally repaired than make matters worse or hide a real problem. I expect that they've BTDT.
__________________
Fred Hoelzle
Reply With Quote
  #5  
Old 09-08-2006, 02:16 PM
EricSilver's Avatar
Registered User
 
Join Date: Mar 2000
Location: Fairfax, VA
Posts: 1,272
Quote:
Originally Posted by donbryce View Post
The trick will be to minimize the area that you'll need to prime and paint. If not, just prime, sand, color coat, sand, clearcoat, and final sand to blend. I just know you won't get it to be invisible, but a good job will not stick out like the sore thumb you have now.
After a straight week of rain, I noticed very small blister similar to that, where the front of the rear bumper meets the fender.

I peeled back the trunk liner to check for inside corrosion, and there is none. Appears to be just some paint flaking and light rust due to water accumulating at that spot, where the bumper and fender make contact.

I plan to scrape away the loose paint, sand the exposed area, and apply the Mercedes touch-up paint. The body color is 040 Black, which I understand is not clear coated. Should I be using a primer/filler on such a small area (a half-moon shape, approx the size of half a nickel)?

I made this discovery while examining some abrasions on my rear bumper, after I scraped a dumpster while parking. My second question is: Is blending simply a matter of painting-sanding-clearcoating-sanding and then clearcoatiing again? I ask because the Mercedes bumper touchup paint appears to be wee bit darker than some parts of the bumper, depending on the lighting and angle of the can when comparing it to the bumper. But I am attributing that to optical effects, as well as slight fading of some bumper surfaces over the years. I assume there will be a perfect match after spraying, and certainly after blending.
__________________
2008 E350 4matic / Black/Anthracite

------------------------------------
Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black
Reply With Quote
  #6  
Old 09-09-2006, 09:01 AM
MB, love..hate..love..
 
Join Date: Apr 2003
Location: NB Canada
Posts: 1,173
Quote:
Originally Posted by EricSilver View Post
....Should I be using a primer/filler on such a small area (a half-moon shape, approx the size of half a nickel)? .....
My second question is: Is blending simply a matter of painting-sanding-clearcoating-sanding and then clearcoatiing again? ... I assume there will be a perfect match after spraying, and certainly after blending.
Whether you'll need filler or not depends on the penetration of the rust, under the paint/primer. If it has etched small pockmarks in the surface, which will be apparant after the rust has been removed, you might need a skim coat of filler. Often, a thick primer will do this for you. I avoid spray bombs of primer if that is the case (way too thin, which it has to be to go through the nozzle). I use a urethane primer-surfacer, mixed to manufacturers spec, and sometimes a wee less reducer to thicken it up.
As to the blending process, you need to think of the surface of the damaged area, after final sanding of your primer and/or filler, as being just below the surrounding area by the thickness of the finish paint coat(s). If you are using straight enamel (sprayed from a bomb or paint gun), just build the repair surface up to just above the surrounding paint, then sand it down until you are level (I use lots of 2000 grit wet). You'll see the blend when the edge of the area around the spot begins to get removed by the sanding.
If you are using base/clearcoat, color fill to just cover the primer with enough to blend with sanding, then clear and sand level like enamel.
__________________
1986 560SL
2002 Toyota Camry
1993 Lexus
Reply With Quote
  #7  
Old 09-09-2006, 06:08 PM
EricSilver's Avatar
Registered User
 
Join Date: Mar 2000
Location: Fairfax, VA
Posts: 1,272
Both paint jobs went well.

After some sanding and primer, I was able to brush the touch-up paint onto the fender, which I will sand smooth after the paint fully cures in 24 hrs or so.

The bumper was easy. I was able to sand away all of the scratches, except for the longest, deepest one, with 400-grit sandpaper. The bumper spray from the dealer ($40.00 ) matched perfectly, and after applying clearcoat I could not differentiate the new color from the existing, so no blending was necessary.

Thanks for the good feedback.
__________________
2008 E350 4matic / Black/Anthracite

------------------------------------
Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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




All times are GMT -4. The time now is 12:45 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page