Well, we have finally gotten paint on the '55 T-bird we are building for Penny and Richard Weiss as well as Jeff Lanier's 54 Studebaker. As I reflect on the amount of time we have in these, and other, projects, it never ceases to amaze me the contrast between the time spent prepping the car for the paint process and the actual act of spraying the paint.
The prep process begins way back in bare metal. We spent a lot of hours, after the paint has been stripped off, getting the metal clean enough to seal it up in the initial coats of epoxy primer. Within this process are any combination of grinding, sand blasting or sanding via d/a or by hand. Bear in mind, this is all done after the initial stripping of the previous finish. Once the metal is as clean as it can be gotten, two coats of high-quality epoxy primer are applied as a sealer/moisture barrier and adhesion promoter. This step is critical and not optional in my humble opinion. Ultimately, this will be the foundation upon which we build our monument to reflectivity: the Paint Job.
After the metal is cleaned, we move on to metal replacement or repair. It is decided whether to repair the panel involved, or replace it, depending on our available options. Sometimes, with a popular car such as a Camaro or Mustang, decent (not good, but tolerable) replacement panels are available for, at least, the most problem prone areas; but, lately this includes just about every area of these common cars. These panels are not perfect. They ALWAYS need work to make them fit well, but if your car has has severe damage, or rust, it may be the best option. By "needing work" I mean that it could be necessary to cut and weld edges, tweak the panel to remove twists in them, add or subtract metal, shrink or stretch panel flaws or maybe more. These parts should be viewed as starting points and nothing else. To be fair, the original cars did not have our current "Lexus" level of fit and finish anyway, so forgive me if I seem like a 'hater'. I'm just talking the realities of it here. I do appreciate the availability of these parts over having to constantly hand fabricate patch pieces or cut up an original part that has long ago seen better days.
Once the metal is brought back into shape, and epoxy primer is re-coated over any part of the car where our work had damaged or removed the coating, we can get into one of the most challenging and misunderstood parts of the process: Bodywork. There has long been a stigma of what proper bodywork technique is. Is it okay to coat a project in body filler ('Bondo', 'pink metal', 'bodyman in a can') and use that to refine the surfaces prior to block sanding? In a word: yes. But only if all the precautions are heeded and you don't abuse the product. I have re-repaired more poor work from other "builders" than I care to remember because of body filler abuse. The next obvious question is, "What is 'Bondo Abuse'?" Hey, thanks for asking. In my experience it means to keep the filler thickness to 1/4" or less. We, and most shops, use body filler as a 'skim coat' to even out the inconsistencies from panel to panel, as well as fine-tune the size of panel gaps, etc. It is not for hole filling, or the 'artistic' sculpting of missing features or shapes. I have seen the stuff over 4" thick at times. It is amazing how people abuse it, yet it actually holds up, at least temporarily. You should be able to get your panel fit and metal repairs to the point where 1/4" or less of filler will level out all the issues Will one 'coat' take care of it? Not usually. No matter how well you wipe in on, there will almost always be a low area, or some issue that needs repetitive applications. Just accept it and have fun. At this point you are taking what the original part gave you and making it better.
At the end of the filler work you may have small areas that need attention, or pinholes (air pockets the resulted improper mixing) that need filling. There is another filler product that will help you refine your work to the point where primer can be applied. It is called 'Poly Putty' or "Body glaze" among others industry names. Basically, it is a body filler, just much more refined. It is smoother, and much more 'runny'. It tends to level out on flat surfaces where regular body filler does not move once you have spread it. It also tends to sand easier as well. Once the putty/glaze has done it's work, we reseal the repair panels with another coat of epoxy primer, give it enough time to dry, or flash off, and then apply the initial layers of the primer-surfacer that will be used via block sanding to further level the surfaces.
At the risk of boring you, I will bring this little session to a close. I will return soon with another chapter in our little book about priming, block sanding and the things that move us closer to the goal here: the Paint Job.
Thursday, April 2, 2009