No powder coater in their right mind would take a freshly-blasted piece of steel and dunk it in water.
Because ferrous substrates are particularly prone to rusting after they’ve been blasted…and if there’s one thing the finishing industry hates, it’s rust.
So why do well-intentioned people – who have devoted their lives to fighting corrosion – continue to spray moist, oily air all over vulnerable metal substrates?
Probably because they don’t realize they’re doing it.
I blogged recently about setting up your air compression system to keep moisture and oil off of your parts. That’s all fine, but it’s half the battle. The real test is whether you’re able to maintain that initial air quality.
If oil sprayed out of your hose in a stream every time you needed to change a filter, life would be a whole lot simpler. In reality, oily (or moist) air won’t be obvious until the fish eyes appear, at which point it’s too late. It’s boring, but it’s true: consistent, high-quality coatings depend on consistent, high-quality air. In even more boring news, consistent, high-quality air depends on consistent, high-quality maintenance of your air system.
Develop a maintenance plan. Monitor your compressed air, and collect data. Check back every day, if necessary, until you’ve mapped out how long you can reasonably expect your filters to last, then schedule maintenance reminders at those intervals. Your mileage may vary, but I would count on performing routine maintenance every two months, and more extensive maintenance – i.e., depressurizing the system completely – every six months.
Note that an oily filter is a working filter. If it never needs replacing, it’s not doing its job. Ease of replacement should definitely factor into your shopping. Reach out to me if you have questions about Kaser’s preferred brands – I’d love to give recommendations. The goal is for your filter maintenance to be manageable in-house. “Effective” does not have to mean “complicated.”
You wouldn’t pour water on blasted steel, so don’t unknowingly invite moisture into the blast booth. Check your filters, and get used to replacing them.