Tower Paint - An Investment
Tower maintenance often includes the removal and reapplication of a fresh coat of paint. Removal of rust and corrosion will protect the structural integrity of your tower. The new paint will seal and protect. This prevents further rust and corrosion ocurring on the substrate (underlying tower surface material). New paint also allows you to avoid potential fines in the case of failing to maintain brightness standards as set forth by the FAA.
How Many Coats?
Each tower is unique depending on structure material, surface condition and environmental factors. But in general, a three coat system works well for most towers – with two being the minimum. A prime coat – or “spot prime” – will be the first coat. This primer ensures the final coats of paint have good adhesion and conformity of coloring. The prime coat is followed by an intermediate coat, which is usually a different chemical mixtured compared to the primer. A final or top coat will be applied afterward.
Coating Thickness Gauges
Coating thickness gauges are also referred to as paint meters. These instruments are used to measure the thickness of the paint – also known as dry film thickness. Measuring the dry film thickness is probably the most critical measurement in the entire coatings industry, not just for tower painting. These gauges can provide important information such as the expected life of the substrate (tower structure), the paint’s fitness for purpose and its overall appearance. As mentioned already, appearance is key when ensuring brightness standards are met.
There are two main ways to test paint thickness – destructive and non-destructive testing. As the name suggests, non-destructive testing does not alter or remove any of the paint applied. Destructive testing will remove enough paint to measure the dry film thickness. The device shown above is an Elcometer digital mil gage, which performs thickness testing in a non-destructive manner.
Measure Twice...Cut Never
As the old adage goes “Measure twice, cut once.” Of course cutting isn’t typically involved when painting your tower. But ensuring that your new tower coating meets all manufacturers recommendations for dry film thickness is critical to a successful tower maintenance and painting project.