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Talking Training - Air Superiority

After investing in a quality booth and spray guns, along with a decent compressor with plenty of capacity, don’t forget the booth air regulator / filter unit, says John Hristias, PPG Business Support Manager Asia / Pacific.

It’s a bizarre situation we see all too often. A collision centre will spend significant money to ensure its air compressor is up-to-date, the booth is well maintained and the painters have top-notch spray gun but then become total cheapskates when it comes to installing a booth air regulator / filter unit that can handle the task. While the compressor, the booth and the spray guns are all important factors, I would argue that the booth regulator / filter is at least as critical, if not more so.
Powering your spray gun
When you stop to think about it, the compressed air supply is actually the only thing powering your spray gun. You can go to the effort of choosing a quality spray gun, such as the latest SATAjet X 5500, fitting it with the appropriate nozzle set and then adjusting it to the perfect application settings but that can all be undone by one thing – the booth regulator / filtration system. A cheap unit can impact in a number of ways:
  • Air quality – When a problem arises in the spray booth, the tendency is to always blame the products being used. However, when you consider how much effort paint brands put into testing and manufacture, it’s rarely the products. Just a tiny amount of contamination – oil, water, etc – getting through the filter and into the paint layer and can cause issues. Generally, contaminants are virtually invisible to the technician but they can lead to issues such as delamination and stone chipping.
  • Air quantity – When you pull the trigger on your spray gun, you need to know your compressed air system can keep feeding it with the required volume and pressure to perform correctly. Typically, cheaper booth regulator / filter units only store 30 cubic feet per minute (cfm). Plug in a HVLP spray gun (approx. 15cfm) and an air hood (approx. 17cfm) and you are already over 30cfm! However, invest in a high quality SATA three-stage regulator / filter system and you get a unit that holds 90cfm of volume very close to where it’s used. You actually get faster flash-off because the paint material is more finely atomised and clearcoats, in particular, are glossier.
A breath of fresh air
A key point that should never be forgotten when choosing a booth regulator / filter system is that it also supplies the breathing air for painters. This is where a little penny-pinching can risk health. SATA’s range of regulator / filter units are not only designed to deliver the air volume and quality that modern refinish systems need (waterborne or solvent-borne), they are also capable of deliver technically pure air for painters to breath. SATA actually launched its first air filtration unit shortly after its first ever spray gun, back in 1925. Since then it has been at the cutting edge of filter technology and it’s easy to see by looking at the latest SATA 400 Series. For a start, SATA filter cartridges are significantly larger than conventional ones (up to half as big again) which means they hold a large volume of air in reserve so you get consistent airflow. For the second ‘fine filter’ stage, SATA uses paper which is state-of-the-art. The paper is folded over and over to create much more filter surface area – more than three times that of a conventional cartridge! A triple stage filtration unit is required for waterborne and that adds an activated charcoal cartridge to remove any traces of oil or solvent vapours.
A clever investment
When you do the math, stepping up to a high-quality booth air regulator / filter system, such as the SATA 400 Series, is a cheap overall investment for the business. For instance, if your collision centre processes around 20 jobs per week, the annual scheduled replacement cost of cartridges in a SATA three-stage filter unit is only around $1 to $2 per job! Considering what just one rework costs or all the issues it causes if paint technicians get sick, this really is an insignificant cost. And it’s not just the time, materials and frustration of the rework, itself, it’s also the job you could process while the rework is being done.
Maintaining the standard
Even high-quality filter cartridges won’t last forever and will need to be replaced. However, as the calculations point out, the overall cost is not expensive in terms of purchase price and especially not if you throw in the cost of the odd rework. As part of the installation, it’s vital to set up a maintenance schedule (and someone responsible for it) to ensure filters are cleaned or replaced at their specified intervals. SATA filters include a handy indicator which clearly shows how long until the cartridge requires replacement – once it turns completely red, the cartridge should be changed.