How to Spray Primer Including Equipment Setup Recommendations
About Primers
Primer is a key part of finishing as it is the first coating applied. Many times the primer is the key coating to promote adherence as it allows for a smooth base upon which your finish coatings can be applied. Primer is also vital in helping coverage of stains as well as providing protection of the substrate to which it is applied. With such a vital role in achieving the coating performance you desire, proper application of primer is essential. In this article we will discuss common primer types and their application equipment that is best used, at the end we will also point to a few instructional resources.
Automotive Primers
Automotive Finish Primers – Automotive Finish Primers provide a smooth base on which to build your top and clear coats. Proper application is the foundation for applying the top and clear coats. With a poorly applied primer the rest of your work will not appear well. For automotive painting the majority of the time a Gravity Fed Spray Gun will be used, to best paint automotive primer we recommend a 1.4 MM – 1.6 MM Fluid Nozzle with your gravity fed spray Gun and an appropriately matched air cap. For a overview of choosing proper atomization you can review the video on how to use a pressure pot to understand how to know a spray gun is atomizing well, for tips on applying the primer check out this video.
Industrial Primers
Industrial Metal Primers – Industrial metal primers are important as they help promote adhesion as well as substrate protection. Due to the higher production associated with metal applications and the higher viscosity of metal primers a larger fluid nozzle is recommended a 1.8 MM fluid nozzle with a pressure fed spray gun. Ultimately it is your preference and it can often be beneficial to try a few different nozzle sizes to see what makes sense for your production needs. The Binks Trophy Spray Gun offers a 1.0 MM, 1.4 MM, and 1.8 MM nozzle all for the price of a single nozzle and can be a great option for a variety of industrial primers as well as other coatings. For an idea of how to use a pressure pot and spray gun check out this instructional video.
Wood Finish Primers
Wood Finish Primers
Wood primers are essential because of the difficulty of achieving adherence from your coating with wood products. If you are using a spray gun with a siphon feed a 1.8 fluid nozzle is often ideal, siphon fed spray guns require adjusting input air until the desired atomization is achieved. If using a pressure fed spray gun it can often be beneficial to try between a 1.4 MM to 1.8 MM nozzle to see what will meet your needs.
Airless Paint Sprayers and Primers
Spraying Primers with Airless Spray Equipment
Primers can also be applied well (with the exception of the car) with airless spray equipment and even air assist airless equipment (which is often utilized in the wood working industry). The difference with airless and air assist airless equipment will be a lot more production which is often not a good fit if you do not have a large product target. Airless spray tips are numbered with systems like 317 or 517 the first number is doubled to give you the fan pattern (6 or 10 inches) and the second number is the airless spray gun tip orifice, the larger the orifice the more paint you will put out. Typically somewhere in the range of 0.15 – 0.19 will be ideal for airless application of primers, for specific advice it is always recommended to have the exact coating being applied as well as how thick of coverage is desired. To adjust an airless or air assist airless paint sprayer you slowly increase pressure until you have an even spray pattern (no tails in your spray patter) or for further in depth training on airless check out this training video . The only additional step with an air assist airless paint sprayer would be to incrementally adjust the assist air pressure to provide an extra level of atomization which will result in a finer finish then a strict airless paint sprayer with a better transfer efficiency.
By using proper equipment and learning from the included training links you should be able to spray primer without a problem. How about you, what stories do you have about spraying primer or if you want to discuss your primer application challenges leave a comment or you can get in touch with us as well.
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