Daily Archives: December 30, 2011
This 2011 BMW 750Li arrived in the shop for minor repairs after a dust-up. Before I get into the repair, let me talk about this … starship … for a minute.
The 7 series the the flagship of the BMW line with every bell-and-whistle in the BMW inventory. I don’t know if this is a loaded model, but it has power everything and hot and cold running everything else.
Slamming the doors to your car is so … pedestrian, so this car shuts them for you with a gentle click. What I found equally interesting is how the doors open. On most every car I have seen the doors have two or three indents that hold the door open. On this car, where ever you stop the door is where it stays. I stood there for at least two minutes opening the door to different positions and turning it loose just so I could admire the fact that it didn’t try to open or close. Yes, I am easily amused.
A lot of cars have heated seats if your tushy gets cold, but not as many have air conditioned seats for when your tushy gets hot. This one does. After a hard day in the shop during the hot summer a cool breeze on your … back … would feel pretty good I imagine.
Have trouble parallel parking? You won’t in this car. Pull up, put it in reverse, take you hands off the wheel and it parks itself. Amazing, if terrifying. I’m not sure I would have the nerve to sit there and let the car do all the work … steering wheel spinning and the brake and accelerator working by themselves. Brings a whole new meaning to the term a computer crash doesn’t it?
You know those blind intersections where you can’t see before you pull out into traffic? To help you avoid bending up your fancy new BMW, BMW has fitted cameras to the nose that allows you peek around the corners before pulling out. I think a lot of the technology on this car is a little over the top, but that peek around the corners thing, now that’s handy.
Of course I didn’t actually get to play with any this stuff, well, except for the doors. Partially because it is a customers car but also because I was afraid to touch anything lest I end up in orbit around Saturn or something. I drive a Toyota now, but I think when I make my first bazillion dollars I might buy myself one of these. Or two.
Anyway, after I finished playing with doors, I got down to repairing the car. As you can see in the first two photos the car isn’t badly damaged, but who wants to drive around in a car this nice with a crinkled fender and creased door?
After removing eleventy-million fasteners we finally were able to get the front fender off. The door we can repair, but it will be quicker, easier and cheaper to just replace the fender. While a BMW 7 series is held together with nuts, bolts and fasteners just like every other car, where a Honda will have four, the BMW had 10. Or 20. Which is probably part of the reason the doors sound like a vault door when they shut the car won’t squeak and rattle after the first 100,000 miles.
The fourth photo shows my 9-year-old daughter sanding on the door while I worked on something else … and if you believe I let my 9-year-old sand on a $100,000 car, I have some Tennessee coast land to sell you. No, this photo was staged purely for my amusement and the amusement of my family.
But the door did need to be sanded after the application of the body filler to fill the crease in the door. You can see the body filler smeared on the car in the fifth picture, and where I sanded it off in the sixth. The masking is in place to protect the rest of the door from primer over-spray.
The next photo, the seventh, shows the damaged part of the door primed to provide protection from rust and to give the paint something to stick to. Because the paint isn’t failing on this car, after all it is less than an year old, the rest of the door can just be sanded, causing the paint itself to act as the primer for the paint that follows.
The Christmas holiday delayed things a bit, but after we received the new fender it went right into the booth to be trimmed. Trimming a body panel, such as a fender, is preparing the panel for paint in all the places you can’t reach after the panel is attached to the car.
Pictures 8 through 12 show the fender going through the trim-out process. The fender is sanded to ensure that the factory applied primer is smoothed to my satisfaction, then the edges, the places where the panel may have rubbed against the box or otherwise have been roughly treated, are primed to make sure that the fender is as well protected after the repair as it was before.
That bit of white stuff above the fender well on the back of the panel is some factory applied sound deadner. It is the small details like these that cause cars like this to be as silent as a bank vault … and part of the reason they cost as much as they do.
The next set of pictures, photos 13, 14 and 15, show the fender back on the car and the car in the booth. When you look at the 7 series, especially the “L” version which mean long, lengthened or limousine, depending on who you ask, there is no doubt it is a big car. But when you roll it into the paint booth, it become apparent just how big the car really is. It fit, but just barely. Look how close the booth door are to the back of the car in the first photo of the car in the booth.
These three pictures show the car after the color layer has been applied. We painted the fender, of course, along with the drivers door, then we blended the paint across the rear door and hood to insure an undetectable repair.
Blending is a technique to reduce the cost of a repair. Because it is nearly impossible to get a perfect color match when painting a car, the new paint is blended into the original paint. Because the paint is so very close in color, when the paint is blended in this manner, the human eye is unable to distinguish between the newly applied paint and the original paint. This allows a skilled painter to paint only one section of a car without the expense of painting the entire side. Without using the blending technique, if the new paint were to end abruptly, say at the body line between a fender and a door, even though the color may be very, very close, the human eye will be able to see the difference. Without blending the entire side of a car would have to be painted when only a repair to fender was all that was needed.
The paint looks flat on the car in these pictures because it is flat. The color layer dries to a dead flat finish. It is the clear coat layer that follows that provides not only the protection to the color layer underneath, but it is also the layer that provides the glossy finish that automotive paints are known for.
The next three photos, pictures 16 through 18, show the car after the the application of the clear coat. As you can see, the clear coat makes a big difference in how the paint looks by adding the gloss finish you expect.
After the paint dried we put the various handles, lights and emblems back on the car, cleaned it up, and sent it home with the owners, the damage repaired and all but forgotten. You can see the results of our efforts in the last three photos. You can see in the first of the completed photos that the wheel still shows a ding … that was replaced after these pictures were taken when the car was sent out for alignment.
This was by far the classiest car we have ever had here at JMC AutoworX. I think just having it around raised the general ambiance of this place several percentage points. Not a bad score for this poky little body shop.
And by keeping quite about it until it was done, I avoided giving my insurance agent ulcers by advertising what was in there.
Just like with rattle can paint, if you want car paint to stick, the surface must be properly prepared. That includes sanding and primers of course, but it also means the surface must be clean of any dust, oils or waxes. To remove oils and waxes we use special cleaners to strip them away, but to remove dust you can’t beat a tack cloth.
A tack cloth is nothing but a lint free cloth treated with a chemical that makes it slightly sticky … similar to the back of a post-it note. Wiping the car down with the tack cloth picks up all the loose dust and other particles left on the surface and are indispensable when painting a car.
The second photo show the car after the color layer is applied. The paint looks flat in this photo because it is flat. With multi-stage paint, the type of paint we use here at JMC AutoworX, each layer does a specific job. The color layer’s job is, well, to give the car it’s color. The shine, that comes with the next layer, as you can see in the third photo.
The third photo shows the car after the application of the clear coat. The clear coat not only provides protection for the color layer underneath, it is also the layer that provides the gloss.
After the paint dries we will reassemble the car, get it cleaned up, and get it back to the customer.