Spraying Epoxies – A Complete Guide
Epoxies can be a great protective coating providing superior resistance to corrosion and resistance to a variety of other environments. While they can be a great protective coating, getting them to spray effectively requires consideration of a few key factors. This guide will cover those key factors so that you will be able to effectively spray epoxy coatings.
Factor 1 to consider when spraying Epoxies – Material Pot Life
The first factor you should be aware of when spraying epoxies is the “pot life” of the epoxy material you plan on spraying. Pot life of a coating typically represents the length of time a material can still be applied without having it become to thick and become difficult to apply. Short pot lifes can be problematic because they provide you as a painter minimal time to spray the coating before it begins to become to thick or hard to be able to spray. If your coating’s pot life is less than 30 minutes you often may need to consider plural component spray equipment in order to be able to effectively spray your epoxy coating. This is because with a pot life less than 30 minutes it can be difficult to move quick enough to get your epoxy sprayed on the products surface. It is also important to review the temperature where you will be spraying because typically increases in temperature will result in shorter coating pot lifes. If you need a plural component unit, the type of unit will depend on whether you intend to spray other coatings in addition to epoxy and a variety of other factors.
Factor 2 to consider when spraying Epoxies – Material Viscosity/ Thickness
A second critical factor to consider when spraying epoxies is how thick the epoxy coating is or how viscous it is. This will be one of the more important factors in determining how you will spray your epoxy. For most epoxies you will need a conventional spray gun with a 1.8 mm tip or larger or an airless paint sprayer. The tip size for your airless will depend on the material but will typically be at least 17 thousands and require 3000 PSI to be able to spray. You can find the recommended equipment for spraying an epoxy in a coatings technical data sheet, which can be seen below showing the recommended spray equipment and pot life of a material. For very thick materials the components of the epoxy may need heated prior to being mixed by a plural component sprayer to be able to flow, if your epoxy is 90% solid or more this may be the case.
Factor 3 to consider when spraying Epoxies – The product you will be spraying and Finish
A final factor to consider when spraying epoxies is the target you l be spraying. For large surfaces an airless sprayer will allow you to apply the most paint in the least amount of time, for smaller surfaces or a finer finish a paint pressure pot and conventional spray gun is usually best. Both of these options assume your epoxy coating does not have to short of a pot life, which would require a plural component setup to spray.
Factor 4 to consider when spraying Epoxies – Equipment settings
If you end up using a paint pressure pot you can follow our guide on using a paint pressure pot here for tips on how to effectively spray your epoxy coating, just remember you may have to thin your material slightly to be able to spray it well. For the airless sprayer you will continue to increase fluid pressure until the material sprays in a uniform pattern, you can also follow our guide here. One important note is with either equipment option you will want to stop spraying at least 30 – 45 minutes prior to the material being at the end of its pot life so you do not get hardened epoxy coating inside your equipment and ruin your equipment.
In general epoxies are a great protective coating that can be sprayed. In order to be able to spray them it is important to consider the pot life, thickness, and target you will be spraying as well as consider the equipment settings you will need to use for best results spraying your epoxy coating.
Common epoxy Spraying equipment options
(Product Data Sheet) – Macropoxy 646. (2016). 1st ed. [pdf] Sherwin Williams . Available at: https://www.paintdocs.com/docs/webPDF.jsp?SITEID=SWPROTECT&doctype=PDS&lang=E&prodno=B58W620 [Accessed 7 May 2018].