When you need to have an auto body repair carried out, make sure you are asking the right questions in order to understand how the repair is going to be performed. Here are a few common trouble areas in which to pay close attention to:
New Panels – in the case of replacing a body panel such as a hood, fender or any other part, a big way some shops try to cheat is by skipping on the primer/sealer. New parts come with a thin black primer called an e-coat. For a reason I’m not quite sure, many shops will skip the primer & paint directly over the e-coat. It will add about 20 minutes to the paint process but is very necessary. Skipping this step will result in excessive stone chipping, you’ve likely seen someone’s year old paint job covered in stone chips and usually showing the black e-coat underneath. This is because someone neglected to prime the part. In the case of aftermarket parts often they apply a poor quality primer that needs to be washed off with paint thinner before starting the process, otherwise you’ll have the same problem with stone-chipping.
New Bumpers / Plastic
This is the number 1 failed process in the business, many painters don’t know or don’t want to take the extra steps required for properly preparing plastic bumper covers.
Best Auto Body Shop in St. Louis and Primed Plastic:-
Aftermarket covers are the worst for this, but some OEM can be bad too. There are recommended tests in place to ensure a good adhering paint job on new plastic. Many painters think any bumper that comes primed can be sanded and painted…not true. If the shop is using waterborne they don’t have as much to worry about, a quick adhesion test on the primer with a piece of 2 inch tape is all that is necessary. If no primer comes up, sand and paint. However if the shop is using a solvent system,
Best Auto Body Shop in St. Louis needs to apply paint thinner to a rag and test the primer with it. If any primer wipes up, the entire bumper needs to be wiped down until the primer is removed. It is not a fun process, but necessary and many people can’t be bothered.
This is my favorite way to receive a bumper. Raw plastic greatly relies on chemical adhesion; it needs to be cleaned very thoroughly. Most paint manufacturers recommend a sanding paste (abrasive cleaner) on a scotchpad as a preferred preparation method (plus plastic cleaners, soap/water). I’m so amazed at how many people out there think it’s okay to just scuff a bumper with a dry scotchpad and paint. After it has been prepared properly it will need to have an adhesion promoter/plastic primer applied before top coating.
In either case, if the procedure is done incorrectly it will result in chipping and/or paint peeling from the bumper.
It is always best to remove as much trim as possible when painting anything. (ie. Door handles, belt moldings, mirrors…etc). It ensures no overspray on your trim, but more importantly it allows for a more thorough sanding, cleaning and paint access. When the trim is simply taped up it increases your chance for paint peeling from the edge that’s been taped. Some shops will reduce the cost and tape up the trim. If that’s what you want to do then great, hope for the best… just always be aware of what you’re paying for.
Blending / Color Match
The way vehicles are painted from the factory now, blending can not be an optional step. It is mandatory! There are many reasons why shops can not give you a 100% match to the next panel, here’s a few:
Manufacturers use different paint lines from plant to plant, a slight difference in flake size or equipment will change the color. The biggest reason that blending is necessary is that with metallic paints you can take a color and spray it at a low pressure and it comes out dark and spray at a high pressure it comes out light. There are many other variables, temperature & humidity can change the shade of the paint. Sounds a bit far-fetched I bet. Here’s what happens, the paint hits the panel and if it dries quick the metallic ‘s are closer to the top of the paint film reflecting more light, making it brighter. The opposite when it goes wet.
Now that you have a better understanding on blending, make sure your shop blends. It is done by bringing a bit of color into the next panel, then clear coating it completely. Sometimes they will claim it is possible to butt match a panel & skip the blend. Sometimes it will look alright, sometimes it won’t. But more often than not when you get your car under a different light source….say at night under some halogens at a club meeting, the failure to blend can become very apparent.
Most of this is in reference to body panels. (ie fender to door, door to quarter..etc). When it comes to bumpers it’s a bit of a different game. Bumpers very seldom match from the factory; this is because the plastic is often painted at a separate plant, sometimes in a separate country. Even if they wanted to, the bumpers couldn’t be painted with the rest of the car given the extreme temperature it’s baked at from the factory. With that in mind, many shops will paint a bumper without blending and just try to obtain a close match and don’t blend the fenders because it didn’t match before. If that’s alright with you then great, otherwise have them bring the color into the fenders.