Removing swirls – basic

This is a more long term solution for dealing with swirl marks and involves removing a thin layer of the clearcoat where the swirl exists down to a flat layer where there are no swirls. This requires a cutting polish and a lot of heat to be generated to achieve this and is therefore best suited to a machine polisher, although results can be achieved to a more limited extent by hand with plenty of patience and strength and stamina.

The principle

In order to abrade the clearcoat away we require a cutting polish. A cutting polish is a liquid substance which has suspended in it tiny little sharp particles that when worked into the paint, scratch the surface away. The liquid acts as a lubricant to prevent scouring and the polishes are made such that the paint receives an even amount of these little sharp particles, known as abrasives, so that the paint layer remains flay and you don’t just inflict many more little swirls. Many modern polishes have diminishing abrasives which means that the sharp particles start large and get smaller as they are worked so they cut less and less. Thus they start by removing larger quantities of clearcoat aggressively and finish by removing a fine amount to smooth the surface and leave it flat with the swirl removed.
This happens automatically with quality polishes as you work the machine, so you don’t need to do anything other than keep working the product until it begins to cure and dry (dusts a little). For deeper swirl marks, highly abrasive polishes (sometimes called compounds) are required and sometimes the sharp particles in these leave some light swirls of their own as they abrade the clear coat. Going over the area again with a Finishing Polish will use much smaller abrasives to flatten the surface, removing the fine swirls left behind to give the surface a nice flat mirror appearance. For this reason, many detailers will use a high abrasive polish and finish with a finishing polish – however, read the general rules of thumb for machine polishing for which products to start with!

Polishes are graded by how aggressive they are. These are combined with cutting and light cutting and polishing pads on a machine polisher. More aggressive polishes work best on cutting pads, the less aggressive ones on light cutting pads and finishing polishes on a polishing pad. Also, you can get both 6″ and 4″ pads – the 4″ pads can generate more heat when used and therefore have more cutting power so are good for more severe swirl marks.

Method

To machine polish, the generic method recommended is as follows. Spread the polish with the machine off over a small area of the paint (2′ by 2′). Turn on the machine at a low speed (speed 3 on PC) and go for one quick pass to spread the polish even more, then turn machine up in speed (speed 5) and go for a single slow pass with increased pressure on the PC head, then turn machine up in speed again (speed 6) and go for multiple slow passes with medium pressure and keep going until the polish starts to dust. Remove the residue with a microfibre towel.

General Rules of Thumb for Machine Polishing

1. Always work out what the least aggressive pad and polish combination required for the task in hand. To do this, start with a light aggressive polish on a light cutting pad. Apply this and examine result. If marks not removed, step up to a cutting pad and repeat. Again examine, and if required step up again to a light cutting pad and so on. Once you’ve got to the least aggessive combination required, proceed to polish the car and if you’ve gone for an aggressive combination be sure to follow this up with a finishing polish to restore surface gloss.
2. Spot repairs – on some cars, there are specific areas of severe swirls while the rest of the paintwork has only light swirls. Only use your aggressive combination on the light swirls and use a 4″ pad for spot repairs and then do the rest of the vehicle with your less agressive combination. I find it best to finish by doing the whole car with a finishing polish to ensure an even looking appearance.
3. *if wanted: follow up the polishing stage with a glaze to add wetness to the shine by moisturizing the paint. (not mandatory!)
4. Always follow up the polishing and glazing stage with a sealant and/or wax to protect the finish.
5. As you can see, you’re effectively removing paint using this technique so machine polishing is something that should only be carried out when required – say every six months to a year, otherwise you’ll end up with clearcoat failure and require a re-spray if you machine polish every other day for example!
6. Swirls you can remove by machine – run your finger across any scratch, if it catches your nail its too deep to be removed by machine and will require filled and wet sanded then polished.
7. Striving for perfection – some swirls will be very deep and to fully remove every single one may require the removal of a lot of clearcoat! Its sometimes best to leave behind the odd deep swirl in favor of keeping most of your clearcoat – the paint will still look immense, and you wont be risking clearcoat failure.