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Fix It Right - Avoiding Substandard RepairsThe worst scenario for a team racing on a budget is to wreck a car and pay to have it repaired—only to discover that they paid good money for shoddy work. Here’s what you need to know to avoid that. From the January, 2013 issue of Circle Track By Jeff Huneycutt Photography by Jeff Huneycutt
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Your mother was right: Accidents happen.
That is a simple fact of life, and racing is no exception. We won’t get into the blame game of who is at fault when sheetmetal and chassis get bent, we’re more interested in getting your car fixed and back out on the track. Actually, the goal isn’t simply to get back onto the track, but to get there with a car that is just as good, or better than it was before the big hit. One of the big problems with repairing a car that’s taken a big hit is that it somehow is just never the same as it was before. Many racing teams working on a limited budget (and let’s face it, that’s most of us) are forced to just live with it. A new chassis is out of the question and there’s no guarantee that the person who did the repair work would get it right if you took it back to have the “repair” repaired. As a result they wind up having to change their setups as a crutch to mask the problems caused by a chassis whose geometry is off. This is an asphalt touring car from a different builder brought to the Hess Race Cars shop for a new front clip after a wreck had caused severe front-end damage. By the time we arrived the damaged tubing had been cut away and fabricator Chris Cornet was prepping the remaining framework for the new front clip. He had already spent nearly an hour centering the chassis on the level plate and setting the car at the proper height.
A quality chassis builder should be capable of repairing practically any wreck damage and ensuring that all the suspension pickup points are right where they should be so that the car handles just as it did before
The truth of the matter is this should never be a problem. A quality chassis builder should be capable of repairing practically any wreck damage and ensuring that all the suspension pickup points are right where they should be so that the car handles just as it did before. It does require an investment in a level plate and jigs, and definitely quality fabrication skills, but it can be done.
 01. This was a different...  01. This was a different car that was in the shop, but it makes an interesting illustration. The team that owned the car installed the engine and suspension in the car as soon as repairs were done in order to hit the track that weekend. They felt they didn’t have time to paint the new steel, so it is easy to see here how the repairs the Hess crew had completed integrated in with the original remaining chassis.  02. Here’s the original front...  02. Here’s the original front clip that had already been cut away when we arrived. The car had taken a hit on the right-front wheel hard enough to collapse the lower control arm and move the entire front clip to the left. Instead of trying to pull everything back into position, it’s easier (and cheaper) to simply cut away everything forward of the damage and weld up a new clip. Plus, the new clip will utilize Hess’ front suspension that has been very successful on the track lately.  03. Cornet used a cutting...  03. Cornet used a cutting torch to separate the damaged front clip from the rest of the car. A torch leaves a bit of a ragged edge, but Cornet says it is preferable to using a saw because it is faster and cheaper when you consider the cost of all the blades you will go through. 04. Notice how the firewall has been wrinkled around the lower support tube. That’s a sign that the tube was bent inward during the wreck. And the gap around the hole on the lefthand side shows that the tube didn’t completely return to position once the bent clip was cut away. Cornet noted all this and determined that the tubing that remains hasn’t lost its structural integrity. He’ll wait to see how the new clip fits up before deciding whether more should be cut away.  06. Here’s an interesting...  06. Here’s an interesting trick: To make life easier and cut down the amount of times he has to change discs, Cornet puts a rough sanding disc both in the standard position and on top of the backing plate. This allows him to sand from both sides, reducing the amount of twisting and “fabricator’s yoga” he has to do to clean up all sides inside that framework of tubing.  05. After finishing with...  05. After finishing with the torch, Cornet uses a disc sander to clean up the rough edges. A grinding disc can be too aggressive and requires a very gentle touch. When doing this you have to be careful only to sand or grind away only the rough edges left by the melting action of the cutting torch. Make sure you do not thin the walls of the tubing that will remain.  07. Cornet and Tommy Byrd...  07. Cornet and Tommy Byrd (foreground) place a portion of the new clip into its approximate position on the fabrication table. Normally, the clips are fabricated ahead of time all the way back to the point where they connect to the framerails. But since this clip is being fitted to a chassis from another fabricator, this clip ends at the spring buckets. Everything from there back will be fabricated specifically for this chassis. 08. This is obviously not the same car, but it is easier to see with this chassis that’s still under construction. Before he can weld anything up, Cornet and Byrd set the ride heights on the level fabrication table. But, like with this new chassis under construction, it works opposite the way most people think. The car is set on a baseline level and then adjusted according to height changes. For example, the baseline number for the ride height may be six inches with the left-rear an inch higher. But for chassis repair and fabrication, the heights work opposite. The car is set up 6 inches off the plate, but the left-rear is at minus an inch (or 5 inches). This way the chassis can still be built on a level surface for accuracy, but once the suspension is installed the left-rear corner will sit 1 inch higher like it should.  09. The correct height for...  09. The correct height for the front clip is set with fixtures that bolt to the table on one end and the sway bar tubes and front pivot for the lower control arms on the other. Remember, the car has already had its centerline established on the fabrication table.  10. The downtubes have been...  10. The downtubes have been left long on purpose. After the correct height is set for the clip, the tubes can be marked and cut to the right height.  11. A cutting torch may have...  11. A cutting torch may have done the work before, but for greater accuracy Cornet uses a cutoff wheel.  12. With the downtubes at...  12. With the downtubes at the proper height, Cornet can slide the clip into place. The fixtures bolt into position on the work table ensuring that the clip stays in line with the car, which—as previously mentioned—has been centered and locked down on the table as well.  13. Finally, the clip is...  13. Finally, the clip is now properly positioned so that the front suspension pickup points are properly aligned, the wheelbase is correct and the ride heights are right. Now all that’s left is to get it connected to the car.  14. Cornet uses lengths...  14. Cornet uses lengths of 2x4-inch square tubing to join the clip to the framerail connectors. We know that most race shops don’t have the time or the hardware to make serious chassis repairs, but every race team should be able to identify when a chassis builder is capable of performing quality repair work. 15. One end of the square tubing connects to the round spring buckets on an angle. The cuts need to be as precise as possible, and the compound angles created by meeting the spring bucket off center can be tough to get right, so Hess Race Cars uses patterns like this made from aluminum sheetmetal to help simplify the process. Hess Race Cars in Mooresville, North Carolina, is a shop exactly like that when it comes to asphalt racing chassis. They regularly build everything from Late Model Stocks to NASCAR touring cars. To show you how it’s done right, we documented one of the toughest repair tests any chassis builder faces. This is an asphalt touring car that took a pretty hard lick to the right front corner and requires a new front clip. Making matters more difficult is the fact that the car was originally fabricated by a different builder. The owner had already noticed the success that the Hess-built cars were having in the series and after the wreck, brought the car to the Hess shops for one of their front clips. Putting a new clip on one of your own cars is one thing, but the task gets much more difficult when trying to fabricate a new clip to a car with different attachment points between the clip and the framerails.
The task gets much more difficult when trying to fabricate a new clip to a car with different attachment points between the clip and the framerails.
Other top-quality chassis builders may vary their methods slightly, but for the most part it all works the same. And we know this works because we’ve seen cars both built and repaired by the craftsmen at Hess Race Cars many times at many different racetracks.
 16. Cornet is still slowing...  16. Cornet is still slowing cutting down the tubing to get the best fit, but you can still see how it is routed to connect the clip to the framerails.  17. To help straighten the...  17. To help straighten the bent down tube, Cornet heats the area with a rosebud tip on the blow torch at the opposite side of the bend then allows it to cool slowly. The heating and cooling process helps pull the tube back into shape.  18. Byrd handled the most...  18.Byrd handled the most finicky job of the day. The rear pivot for the lower control arm attached to the tubing that had to be fabricated to attach the clip to the framerails. Here, Byrd is making templates for the lower control arm brackets. The fixture bolted to the fabrication table located the center point of the pivot, so the brackets only need to connect those points to the clip rigidly.  19. After getting the template...  19. After getting the template to fit like he wants it, Byrd traces the pattern onto 3/16-inch steel plate and cuts it out.  20. You can’t simply butt-weld...  20. You can’t simply butt-weld two pieces of tubing together—it won’t be strong enough for racing. Instead, insert a sleeve—a piece of tubing that will just barely fit inside the original—and tack that in place.  21. Then Cornet slides the...  21. Then Cornet slides the new tubing over the sleeve and tacks that into place, leaving a gap wide enough to hold a good weld bead.  22. When welding tubing,...  22. When welding tubing, Cornet recommends always welding from the bottom up. This keeps the melted steel from the bead from dripping into the area you are welding.  23. Here’s a completed weld....  23. Here’s a completed weld. Cornet also drilled holes into the outer tubes to allow extra surface area to weld the tubes to the sleeve for additional strength. He also says it’s important to set your welder with enough wire speed so that the weld is convex, to extend beyond the surface of the tube. Not only does this help guarantee a strong weld, but it also allows you to grind off the excess for a nice, smooth surface. After the chassis is repainted you won’t be able to tell where the repair was made.  24. This vertical brace stitches...  24. This vertical brace stitches all the separate tubes together to the clip. Whenever you can, always place braces so that they join in one spot and support each other. In other words, create on “X” instead of two “T”’s in separate places. It can make for a tougher job, but your race car will be stronger.  25. Here, you can see how...  25. Here, you can see how the brackets for the lower control arm’s rear pickup is welded to the clip and braced with narrow steel tubing from below. Once it cools, the fixture can be unbolted.  26. Cornet only uses tack...  26. Cornet only uses tack welds until he is confident that everything is positioned perfectly, then he begins the laborious process of welding all the joints together solidly. During this process, he constantly moves from one area of the chassis to another to keep heat buildup from warping the clip he’s worked so hard to position exactly.  27. Here’s a shot of the...  27. Here’s a shot of the repaired car with the new front clip. There’s still plenty of work to be done fabricating fender, hood, bumper and other mounts and brackets, but Cornet is confident that this car is well on its way to competitive status once again.
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