Adopted from Keith Combs’ article in BodyShop Business Sectioning is often the only realistic approach to a repair. But because many of today’s vehicles are a hybrid of unibodies and full frames, consumers get safety and strength, while future repairers, like you, get twice as many precautions for sectioning.
Why talk about sectioning? Because after you’ve been in the industry for more than a week, you will have likely realized that sectioning is the only realistic approach to a repair.
Take, as an example, the door opening and rocker assembly. On many vehicles, this panel is installed during the assembly process before the roof, fenders and quarter panel. So to install this piece in its entirety, you have to remove each of the panels that were installed after the piece in question was put in place at the factory. Fenders are relatively easy, but the roof and quarter panel are normally things you remove only when you’re throwing them away. In order to make a realistic and reasonable repair, you need to find an acceptable method that allows you to replace the damaged portion of these (and other) panels without disturbing any more of the undamaged body than necessary. This method (you guessed it) is sectioning.
One thing that’s caught my attention over the last several years, however, is that unibodies and full-framed vehicles are becoming more and more similar. In the not-so-distant past, if a unibody manufacturer recommended sectioning, there’d be lots of precautions and stipulations. On the other hand, its full-framed counterpart seemingly had a much more relaxed set of sectioning rules.
Not so these days. As body characteristics and construction of modern full-framed vehicles become more like unibodies, the precautionary measures we must take to repair them are also becoming more alike. I’ve even heard at least one manufacturer use the term “body on frame and unibody dual construction,” emphasizing the best of both worlds in their sales pitch: the safety of a unibody, which has crumple zones to protect passengers, combined with the strength of a full-framed vehicle.
What this gives us in the repair industry, however, is a new set of rules for this hybrid of late. Not only do we have the advantages of both, we also have to take the precautions associated with both.
New Materials Call for New Techniques
Now, admittedly, sectioning today’s vehicles involves a few techniques that differ from what the industry used in the ’70s on those multi-hued customs of yesteryear. But some techniques are the same, and the properties of metal you learned about during some of those projects are invaluable (whether you learned them yourself or heard horror stories from the old pros).
Some of the materials we’re working with today, however, are altogether different from the materials we used to work with. And these new materials require our using some methods and practicing some precautions that were unheard of when I started in this business back in the ’70s.
Still, the new materials and designs aren’t that hard to deal with. I’ve resolved myself to treating all of the sectioning I do as if it were being done on a unibody. I also treat the steel components as if they were all HSLA steel, keeping the heat to a minimum and staying away from the historical magical brazing rod. I’ve probably run enough brazing rod on the old cars to stretch half way to the moon, but there’s really very few places on today’s vehicles that brass would be tolerated, let alone preferred.
I can sense you’re preparing yourself for a step-by-step on sectioning a vehicle, but I’m not going to do that because you’d most likely forget the details before you got a chance to put them to use. After all, each individual vehicle typically has its own specific instructions. Instead, I’m going to pass along some general useful rules and tips for sectioning that have helped to keep me and some of my mentors out of trouble.
Hit the Books
When contemplating a repair using sectioning techniques, consult a service manual for the make and model you’re preparing to work on. In the not-so-distant past, there was very little information specific to individual vehicles available for collision repair shops. You had to hope the technician you assigned to the vehicle had a clue about metal-to-metal joining and had been given more than his deserving share of common sense.
Today, there are so many things designed into these components that we can’t just shoot from the hip. We have to do our part by letting the manufacturer do their part designing repair methods and testing said methods to confirm the integrity of the repair. In fact, many of the parts we receive these days come with an instruction sheet detailing sectioning procedures when they’re applicable.
When you get into the directions for sectioning these components, you’ll be amazed at how detailed they are. Some of the repair procedures listed will give you exact dimensions of where to make your section joint and what kind of joint is required. The exacting directions (when available) are a real confidence builder for me. I know I certainly couldn’t begin to do the testing that’s involved in making those directions.
This reminds me of the countless hours I spent as a kid putting together model cars. When building my first few model cars, I scoured the directions, following every detail. But after building a few of them, I got lax in reading the directions. I don’t recommend this – especially when it comes to reading sectioning directions. Updated information can help you to do a quicker and safer repair.
That reminds me of a repair that a friend did early in his body repair career on a total he’d bought to rebuild. Seems this well-intentioned novice decided the best way to repair this aging station wagon was to install a used quarter panel section. After measuring out the parts and carefully making his section joints, he feverishly cut, welded and finished his welds, making good time. The only problem was that when the door was shut, it overlapped the quarter panel by about a quarter of an inch.
After I jokingly told him that he’d have to cut the door down to fit the hole, he knew right away what he had to do. I went back to his shop the next day and guess what? He actually took three eighths of an inch out of the middle of the door, saying that “the window will be no problem because it’s tapered and it just won’t roll up quite as far.” That left just enough room for the gap. I have to admire his ambition, but his execution was a bit lacking. I’m sure it drove fine though, since most of his turns to get home were to the left anyway.
Using Your Noodle
Use every bit of information that’s been tested and made available to you. If the OEM doesn’t have specific recommendations for sectioning (or against it), then find other recommendations. Check out I-CAR’s Uniform Procedures for Collision Repair or Tech-Cor’s recommendations to see if they apply to the circumstance at hand. And remember that when you check out such directions, they’ll almost always tell you to follow the manufacturer’s recommendations when doing these repairs. (Easier said than done.) I said it before, but it’s worth repeating: Use the most valuable tool you have at your disposal – common sense. It’s rare to find, but worth the search.