The fitment of wide, large diameter wheels and tyres is probably the single most common modification that people make to their cars, making them both drive and look better. The very latest trend is towards hugely-sized exotic rims that consume every inch of useable space under the standard guards - and sometimes more. One simple way to create more room for these over-sized wheel and rubber packages is to have the guards rolled or lipped.
What it Gives
In this process, the metal lip that is pressed all the way around the inner side of a wheel arch is folded up and under the guard. Rolling this edge of a guard typically gives you around another 2 centimetres of width to play with, depending on the car's lip, and there's no accompanying need for any structural modifications. However, the extra under-guard room is achieved only on the outer side of the wheel.
This means you are limited to creating more clearance only for the outer edge of an existing tyre. But ideally, after rolling has been done, it is then possible to fit wider wheels with a different offset. This will place the wheel and tyre outward, more toward the centre of the newly available abundance of space.
Any car that has the factory inner guard lip can have it rolled back. Both the front and rear guards can be rolled if necessary, but it is more common to do just the one end of the car which might be causing clearance problems.
There are no hassles with paint cracking as the metal is flexed either, as heat is applied to the paint surfaces prior to and sometimes during rolling. This allows some "give" in the paint, making it tolerate some movement without separation (cracking).
Case Scenarios
Some guards can be more difficult to roll than others, and older cars generally have heavier gauge metal (up to three layers of it!) which makes folding much more strenuous. Most new cars have either a single or dual layer lip that is a breeze to roll. If the shape of the wheel arch isn't exactly round, this can also make things a little more difficult. If this is the case, the position of the guard roller needs to be altered at certain points to achieve an even roll over the length of the arch.
Various types of paint, such as 2-pack, can also be catered for. Depending on the paint on the specific car, there's an extra soft roller that can be used, which eliminates any harshness problems. And to avoid heat damage or cracking, the intensity and duration of the heat gun exposure can also be altered.
Here is the process they use for rolling the inner guards of a typical modern car:
How They're Rolled...
First of all, the car needed to be raised to a working height and to have the appropriate wheels removed.
The next step was to thoroughly clean the area being worked on. This is an important consideration because any grime, dirt particles etc can later get baked into the paint or pressed into the metal via the rolling wheel. It is also vital that the roller itself is clean too. In the case of our Subaru Liberty, the factory rubber trim pieces that lined the edge of the lips were also removed.
An electric heat gun was then applied to the paint around the edge of the guard from a distance of around two inches. Not letting the gun settle in one position for too long, the paint was gradually warmed until it was very hot to touch, but not quite at the tacky stage. Note that the rolling tool was bolted onto place on the wheel hub prior to heating. This enabled the rolling to be carried out before the paint got a chance to cool.
With the paint still hot, the $2000 German-made rolling tool then stepped into action. Its multi-axis adjustment was locked into the correct appropriate position, and the roller was then slowly and carefully rotated around the wheel arch, pressing the metal back by around 45 degrees in the first instance.
If (as in our case) the arch is not quite perfectly round, the axis settings are then re-adjusted to suit the irregular segments of the curve.
Once the metal had been folded back by 45 degrees and everything appeared okay, the rolling wheel was then used for the second (and last) stage of the folding process.
The rolling tool was once again re-adjusted to roll the metal lip into its final position, at nearly 90 degrees to its original position. For our Subaru, we didn't push the lip up as far as normal as we needed to leave a small amount of space to re-install the factory rubber trim pieces.
After the rolling was completed, there were unfortunately a couple of small cracks in the paintwork where the edge of the factory trim pieces had previously been rubbing slightly.
This isn't likely to cause any future metal corrosion problems since only the top paint layer was cracked, and there was plenty of paint and primer still covering the metal. The cracks were out of sight and certainly wouldn't be picked up by anyone who didn't know they were there. However there was one trick left. While the paint was still slightly warm, a coating of clear heavy-duty nail polish was applied over the cracks, which created a seal. Then, after the paint had fully cooled down, another lick of nail polish finished the job. And that was it sealed and delivered.
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