Using heat and a big hammer is the fast way to roll fenders on a racecar build. Done right, the job won’t show any warping or undulations on the outside when you’re finished. We added the decals after heating and rolling the fenders.

When you build a racecar or lower a street car, you often end up with tires that rub on the fenders and quarter panels. That isn’t good for the tires or the body panels, so you have to “roll” the fenders.

That just means rolling the inside of the fenders and quarters up and in so the tire can move freely without rubbing on the sheet metal.

If you’re building a street car or a resto-mod — something you want to look nice — it might be worth your while to buy a fender roller tool. Eastwood sells one for $80, and it’s probably the most mechanically sound way to do the job. The tool attaches to and rotates on the wheel hub and uses a nylon roller that presses on the inner lip with adjustable tension. Use a heat gun so you don’t crack the paint, increase the pressure little by little, and soon enough, you’ve rolled the fender.

The tool works best for wheel arches that are as close to round as possible because it rotates on the hub. It won’t be as useful with cars and trucks with, say, a horizontal upper lip. Eastwood has a great demonstration video on this.

There’s another method that’s similar, but it uses a baseball bat. It works in largely the same way as the Eastwood tool, except you leave the wheel and tire on the car, and roll a baseball bat over the top of the tire so that it presses the inner lip of the fender or quarter panel up and in. It does work, and I have done it that way, but it is almost guaranteed to ruin the bat and you can get wavy results if you’re not careful. It’s also really difficult to roll the bat with your hands.

Wheel liners are one of the first things to come off a new racecar build, which makes rolling the fenders easier.

I’ve seen some guys have a buddy to push the car forward and back to drag the bat over the top of the tire to roll the lip, but that requires two people. I don’t have a good photo or video of that method, but you can search “rolling fenders with a baseball bat” on YouTube and find a number of examples of how to — and how not to — roll your fenders with a baseball bat. There are some real hacks on YouTube who make a hash of their fenders because they don’t use heat or common sense.

The fastest and most effective way I’ve found to roll the fenders on a new racecar build is using a Bernz-o-matic torch and a big hammer. This is the “because racecar” method. It works fine for a racecar, but it’s probably not the best method for a show car or a hot rod. These fenders are going to rub against other cars soon enough, so it’s not critical they be rolled like you would in a painstaking restoration.

I light the torch and run it along the inside of the fender until it’s nice and warm. The Eastwood video suggests using an infrared thermometer, and that’s a good idea. Looks like 150 degrees is about the right temperature for keeping the paint intact as you roll the fender.

In this photo you can see how much the rear quarter panel has been rolled in comparison with the stock sheet metal in the lower right portion of the frame.

Once the fender is warm enough, you grab a big hammer and start pounding on the inside lip using your other hand as a “dolly.” Pound the lip up first, then in. Mechanix Wear gloves or something similar are a must for bracing against the hot metal.

You do the same thing on the quarter panels. They are typically made of thicker metal, so they require more heat, but the method is the same. Hammer up first, then in.

In the video, you see I am using a steel hand sledge because it’s the heaviest hand hammer I have. If you have a really heavy rubber or plastic mallet, that might be a better tool because it’s easier on the paint and if you make a mistake swinging the hammer, it’ll be more forgiving. The right amount of heat and a heavy hammer are the critical elements.

With additional heat and precise hammer swinging, you can roll the quarter panels as easily as the front fenders, which are almost invariably made of thinner metal.

You can see the whole process in the video below. It doesn’t show the rear quarters because I had a camera malfunction, and that can happen when you think you pressed the record button, but you actually did not. The process for the quarter panels is the same, but you have to run the torch along the lip a bit longer because the metal is thicker than the fender.

If you find your tires still rub, you can go back and do it again.

Image courtesy of Brett Becker

1 COMMENT

  1. I bought a cheap fender roller on Amazon. Don’t do that – get a decent one if that is the route you are going. I ended up using an aluminum bat and it did scratch the bat up quite a bit. I made the process a bit easier by jacking the car up just enough so I could get the bat between the wheel and fender and then lowering incrementally as I made several passes rolling the bat. I did this on a ’95 Miata that is a track-only car. Not sure I would use the bat method if it was a “nice” street car.

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