Gloss deception behind flatting marks

While re-appearing flatting marks are a problem that every body shop dreads, refinishing specialist Farecla explains the common reasons why they occur and advise how to prevent them.

With a focus on cycle times and speed of repairs, repairers can’t afford to have any delays on the job or reworks on panels.

Re-appearing flatting marks are a common industry problem. Often the marks haven’t disappeared: it’s just that they weren’t initially seen, perhaps because of inadequate lighting.

Good lighting is often overlooked in the work area, which makes it difficult for the technician to measure progress of compounding, especially on dark colours.

The vehicle often looks okay until moved into natural light or into a valeting bay where lighting conditions are superior.

Many bodyshops would see increased workflow, a huge reduction in compounding re-works and increased profitability if there was improved lighting.

An easy solution is to use a portable end check inspection lamp in order to direct the light where it is needed.

One of the main causes of re-appearing flatting marks is insufficient compounding.
If the marks at the deepest point are not removed, product can be caught in the scratches and as the process is continued, heat is generated at which time the flatting marks lie down and are not visible.

This is often referred to as “gloss deception”, and when the car is washed, the marks become obvious.

Choosing incorrect abrasives and not abrading in the correct way can cause “pigtails”, where half-moon marks can be seen under the surface.

It’s important to follow the correct procedure for any chosen compounding system.
Other reasons are that paint work is insufficiently or improperly cured, or a sanding disc which is too fine is used at the beginning of the process.

Although the surface may appear hard, underneath it is slightly soft and after compounding the solvent in the topcoat evaporates causing flatting marks to appear under the shiny surface.

Farecla recommends using P1500 first, then follow with P2000, to address this problem.
It’s important to use a compounding system that has no solvent or petroleum as these can re-soften the paint work.

Products containing solvents or petroleum can often appear to remove flatting marks quickly, but as the solvent or petroleum evaporates the marks re-appear.

Farecla’s range of water-based compounds contain no filling agents. Using the recommended applicator, which is designed to keep both the product and panel cool during the compounding process, enables the technician to compound to the bottom of the scratch.

By keeping the panel cool there is less risk of the flatting marks lying down, only to re-appear when the vehicle is washed.

When using water-based products which contain no filling agents, if the flatting marks have not been removed you will see them before you progress to the next step in the process.

Good housekeeping is also extremely important.

When using a compound that requires water such as G3, always use clean water to aid lubrication. Using dirty water that was perhaps previously used for flatting with primer can result in grit being in the water that is larger than the grit you use to de-nib. This can cause a V-shaped scratch which is extremely difficult to remove.

For more information contact Australian Warehouse Distributors on (03) 95531997 or visit www.storkawd.com.au