How to Remove Swirls and Scratches
Between the stages of sanding, compounding, buffing and polishing, the one key factor that underpins them all is abrasion. Merriam-Webster defines abrasion as “a wearing, grinding, or rubbing away by friction.” Abrasion occurs during all of those aforementioned stages with varying degrees of aggression, and we implement this because defects in the surface of a vehicle’s paint have one key feature – their depth.
Defects vary in their depth, depending on what those defects are. Let’s explore two different defects and develop an understanding of their severity before we delve into what can be done to correctly remedy them.
Swirl Marks and Scratches
The term “swirl marks” is coined by their swirly appearance. They are also referred to as “wash-marring” or “spider-webbing.” Whatever semantic suits you, swirl marks are ultra-fine scratches inflicted during improper washing and drying techniques or when buffing off products. Essentially, these defects occur when rubbing the car.
“Scratches,” on the other hand, are more prominent defects. Generally, these are deeper than swirls and can be caused by anything from a small piece of grit in a drying towel to a sharp piece of metal drug along the side of a door.
Swirls and scratches look quite different to the untrained eye but are very similar – they are scores in the paint on a very different scale.
Consider this: a dollar bill is around 76 microns or 3 mils thick. Swirl marks can be as shallow as 1 micron or 0.039 mils, making their depth commonly quite shallow, whereas scratch marks are far more inconsistent.
Scratches can be as fine as a hairline scrape or harsh enough to penetrate all the way through the paint to the panel itself. The depth of a scratch determines whether we can either improve them or potentially eliminate them altogether or if new paint is needed.
The way we fix swirls and scratches is by abrading away the surrounding clear coat until we reach the depth of the defect. It is most important to know how thick the clear coat is, as this defines how much material we can remove. A very loose rule of thumb is that factory standard clear coats are generally around 50 microns or 2 mils thick, and if you catch your fingernail on a scratch, it’s recommended to use paint thickness measuring equipment first.
Because of the shallowness of swirl marks, we must be careful. Taking a heavy cutting pad, a coarse liquid, a large orbital or rotary machine, and applying lots of pressure and high speed with multiple passes will remove ten times as much material as we needed to.
It is far more efficient to remove just enough clear coat that the defects are gone. Depending on the machine, we recommend starting with a light cut pad, such as our orange foam SDO or HDO. When combined with a medium-cut compound, the orange foam has enough cutting potential to remove the tiny amount of clear coat required while facilitating a finish down to an impressive gloss.
On softer paints or darker colors, an extra step of refining with a finishing polish and our black or red foam pads from the HDO, SDO or Force lines deliver ultimate perfection.
Much like swirl marks, we want to cut away the clear coat no further than the depth of the scratch. Scratches traditionally require the removal of more material, so it makes sense to select a heavier-cut pad like our blue HDO foam or Microfiber to save time.
Combined with a heavier-cut compound, this coarser combination allows us to abrade away the surface much more efficiently until the scratches are no longer visible. But while doing so, it’s important to check our progress regularly so that we don’t remove more material than necessary. Once a scratch has been rectified to an acceptable degree, switching to a refining pad and polish will restore the full gloss.
When working on an individual scratch, we must localize our technique to protect the surrounding paint areas by considering using advanced pad tilting methods or making a switch to a smaller tool and pad.
As always, practice makes perfect, but it is helpful to have resources on hand. Learn more about our wide range of quality cutting and finishing pads on our social media channels and inquire about our upcoming training programs today!