Ok so we have a squeaky clean car with the paint stripped of any remaining oils, waxes etc. This is what is called a naked surface’.
It’s time to progress onto the correction. Our ‘Minor Paint Correction’ includes a two-stage machine polish. This will consist of a ‘cutting’ stage and a ‘polishing’, or ‘refining stage’.
The first step is a paint inspection. Every part of the car will be inspected to identify any problem areas, or areas that could be dangerous to use too high a cutting combination. We are also looking for the types of imperfections in the paint, be it swirling, haze, sanding marks, random deep scratches, overspray – the list goes on.
Below is a general guide to the types of defects commonly found the relevant depth of these defects.
If we notice any damage that could be dangerous we mark this simply with a piece of tape. This could be anything from thin clear coat to a burnt through panel edge.
In preparation for cutting what do we need to consider? Before the pad is put to paint we will take paint thickness measurements. This is crucial and will allow us to gauge the thickness of the paint.
Experience comes in here. A thickness gauge will measure the total paint thickness including base coat, colour coat, and clear coat, (unless single stage paint system). We are looking to remove as many defects as possible without removing too much of the clear coat.
A modern paint system is comprised in layers on top of each panel, be it plastic or metal. Onto the panel is sprayed a ‘primer coat’. The thickness of this has reduced in modern times as panels are generally created by a machine and therefore imperfections have reduced, thus reducing the amount of primer required.
Sprayed onto the primer is the ‘colour coat’. This contains the pigments which make up the colour of your car. It also includes any features within the paint – e.g. metallic flake.
Finally onto the colour coat is sprayed ‘clear coat’. This is basically clear paint and provides the layers underneath with UV protection to prevent the colour going dull. I’m sure we have all seen the once shiny red car go pink.
The paint thickness gauge will give us a good idea clear coat thickness and how far we can go, and what combination of pads and cutting compounds we should use. It will also allow us to tell if a panel has been re-sprayed and how it might react differently to the combination of pad and compound.
We also have to consider the type of paint a car is wearing and if a coating has previously been applied!
There is a vague rule of thumb about paint hardness. HOWEVER, this does vary and experience plays a huge part of this. Another reason you can’t just pick up a machine polisher and become a detailer and charge a hundred quid for an all over polish.
Once we have taken countless measurements over the whole car we start taping up the major parts of the car where we don’t want to make contact with the polishing pad. This includes items such as the rubbers, plastics, badges & side repeaters.
Additional taping will be applied as we polish. For example, if we are to polish the front wing, tape will be applied to the light clusters to prevent the gap filling with polish and also, prevents any damage to the surface of the cluster.
So on to the cut. There are so many combinations of pads and compounds that we could use here, this blog would become a novel, so we are just going to focus on what we might use for a typically hard European paint system.
We always start with a light combination in a test section working up the combination to a heavier combo until we are satisfied with the results.
After testing sections with pad and compound combinations we generally go onto the main cut with a microfibre pad and a heavy cut compound, (we will be doing product reviews in the future on products we use and why we use them so we will keep it generic here).
The next blog will focus on ‘how we cut’ and the processes we follow – stay tuned for part 4 – ‘The Cut’.