Spraying Adhesives- A Complete Guide
Why Spray Adhesives?
Spraying glue or adhesives is a common application for a variety of industries including woodworking, drywall manufacturing, and a variety of other applications. Spraying is by far quicker than hand applying. To be able to properly apply adhesive with a spray gun, you want to ensure that you select a proper type of spray gun as well as proper fluid supply equipment to be able to spray effectively. In this article will cover all the different factors to consider to ensure you can properly spray your adhesive.
Factor 1- General Considerations
Since most forms of glue are more viscous than a lot of other coating materials, you typically will need to spray adhesives with a conventional spray gun. Conventional spray gun will be most effective at atomizing glue allowing you to effectively spray across the surface. If you try another technology like HVLP or LVMP you may not be able to adequately break the glue apart or achieve the desired pattern for spraying.
Factor 2 – Is the adhesive water-based or solvent based
In general water-based adhesives are more viscous than solvent based adhesives. Additionally, water-based adhesives are more corrosive to the majority of metals than are solvent based adhesives. Since water-based adhesives are more viscous in general, you typically need a larger fluid nozzle then you use with solvent based adhesives. One common option for spraying adhesives is a Binks 2101-4308-2 which is a conventional spray gun with a 1.8 Fluid Nozzle and High CFM Air Cap. The large fluid opening allows you to spray high viscosity material like water based adhesive. Additionally, all spray gun components are stainless steel that are exposed fluid which will help to prevent any issues with corrosion. If your spraying solvent based material, you’ll typically use a similar air cap with a slightly smaller fluid opening. The smaller fluid opening will be effective because material is not as thick allowing it to be supplied effectively with the smaller nozzle. A Common option for solvent based coatings is the Binks 2101-2808-2 which is the same type gun that is used for a water-based material but with a smaller fluid nozzle.
Factor 3 – Where will you feed material from?
If you will be applying adhesives in high volume like from a 55 gallon drum you will typically want to consider a double diaphragm pump or a transfer pump. The advantage of a transfer pump is the ability to pump material at an increased pressure, which can be needed when spraying higher viscosity adhesives. If you will be considering a double diaphragm pump, typically want to try to ensure your diaphragm pump has stainless steel balls and seats. Stainless steel balls and seats will help reduce issues with the pump becoming stuck due to the adhesive.
If you will be spraying adhesives in a smaller volume, you can consider a basic pressure pot system. The important thing to remember is if you are spraying water borne adhesives you want to consider getting a stainless steel pressure pot so that you do not experience significant rusting in your pressure pot. If you are spraying solvent based adhesives, you can typically use a standard zinc plated or galvanized pressure tank.
Factor 4 – Is the adhesive a plural component adhesive?
If your adhesive has two components that are mixed that result in an instantaneous bond or near instantaneous bond, you may needto consider a plural component application system. A plural component application system will keep the two components separate and use a plural component spray gun to mix the two components at the tip of the spray gun. By mixing the two components just prior to the products surface you can eliminate the issue of the adhesive prematurely hardening and ruining your spray equipment.
Ultimately spraying adhesive can help improve production in a variety of applications. To be able to spray adhesive effectively you should match the appropriate type of spray gun and fluid dispensing equipment for your adhesive application. If you have questions about beginning to spray adhesive or problems spraying your adhesive contact us at any time for a free adhesive application consultation.