Spraying Mold Releases: A Complete Guide
What are Mold Releases?
Mold releases are lubricant-type products that are most often applied to a part or mold in order to either prevent the sticking of the product during a process such as welding, cutting, pressing, etc. Mold releases are also often applied to a form that a liquid or semi-liquid material is then poured or dispensed into so that it can then be cured or formed into a final shape.
Put most simply, mold releases are used to prevent excessive sticking of a material to another material. By preventing excessive sticking of two products, you can ensure the part you’re making or the process you’re performing is not negatively impacted by the two substrates fusing together.
When are Mold Releases Used?
Mold releases can be used in processes as varied as making hoods for cars to prepping pans in a bakery. Mold releases are used in a ton of different processes to prevent a substance and surface or two separate surfaces from sticking together.
Spraying Mold Releases
A question we are often asked is if you can spray mold releases using spray equipment. While there are a variety of mold releases on the market, in general, they tend to be relatively thin and so can be sprayed effectively. Spraying mold releases is common in a variety of manufacturing applications from prepping molds for resin processes to prepping machinery for stamping processes. Spraying mold releases has a lot of benefits that we cover below.
Benefits and drawbacks of Spraying Mold Releases
Spraying mold releases ensures you achieve a more uniform mold release application. Usually, when applying mold release, your goal is to coat a surface with a light amount of release in order to prevent two substrates from sticking. Also, you don’t want to over-apply mold release so as not to create pockets and defects in the part you want to work on. Additionally, excessive application of mold release agents can increase process costs. Spraying mold releases gives you three great benefits: efficiency, the potential for saving material, and the potential for thin mold release coverage. Potential material savings can be possible as you may buy mold release agent in bulk rather than in small quantities which can reduce your material costs. Furthermore, by spraying, you can often reduce the amount of material you apply to the mold which can reduce your mold release agent costs. Finally, using a spray gun can be faster than rolling or another application method and help apply a thinner coat of mold release.
How to Spray Mold Release Agents
Now that we have gone over the purpose of mold release agents and the pros and cons of spraying mold release agents, we can get into how you can spray mold release agents. While there are a variety of mold release products on the market, they are all typically thin to medium in viscosity, which makes them well suited to being sprayed using spray equipment.
For applications where a medium to a high volume of mold release agent will be used at a time (0.5 gallon or more per working session), we typically recommend considering a pressure feed spray equipment outfit. Pressure-fed spray equipment allows you to use a larger material container (2-quart, 2-gallon, 5-gallon, or even 55-gallon drum options are available). Pressure-fed spray equipment will also allow the most control of how much material you apply and how fine the release agent is broken up when being applied. For the spray gun, a 1.0 to 1.4 tip would be the most common tip size to use as the mold release agent is not thick. The specific tip would depend on the size of the surface you’re spraying and how fast you want to spray the surface. A 1.2 mm tip is a great starting point and you can go with a smaller or bigger nozzle depending on your specific application.
To spray small volumes of mold release agent (0.5 gallon or less per use), a gravity-fed spray gun could be the perfect route to go. While it may be a bit slower than a pressure feed spray gun, clean-up will be a lot easier. You can still use a pressure-fed setup for small quantities as well, and if you plan to spray a large quantity of product at a time in the future, it could be a great option.
The spray gun you use for mold release should be HVLP unless you’re spraying a thick heavy mold release (which is not that common). An HVLP spray gun will provide the greatest painting efficiency and keep your mold release waste from spraying down to a minimum.
Spray Gun Settings for mold release agents
In general, you don’t need a lot of fluid pressure to spray mold release agents. We recommend starting with a pressure of 7 to 12 psi on fluid pressure and then adjusting up for more mold release or down for less. Our guide on using a paint pressure pot can better help you set up your equipment to effectively spray your mold release. You usually want to use no more than 30 pounds of air pressure as higher air pressures will create more overspray and create more waste.
For a gravity-fed spray gun, you can use a 1.2, 1.4, or 1.8 tip. A bigger tip will be needed to allow the product to flow through the gravity cup. If you cannot get the mold release applied thin enough, or when you apply it, it is too blotchy, trying a smaller fluid nozzle or more air pressure will be the best option.
If you will be spraying water-based mold releases, you should consider using a liner with your pressure pot or using stainless pressure pots.
Popular Equipment to spray mold release
Medium to Heavy volumes
Binks 98-3156 Trophy Air Spray Gun & 2.8 Gallon Zinc Plated Pressure Tank w/ Dual Regulated
98-3156 Binks Trophy HVLP Air Spray Gun Pressure Feed 2.8 Gal Pot Outfit. The Binks Trophy (98-3156) Pressure Feed Spray Gun & 2.8 Gallon Pot Outfit comes in 5 configurations perfect for everyone from craftsmen to production shops. Available in complete gun and cup systems and higher production outfits. Binks pioneered the development of liquid spray finishing technology over 100 years ago and continues to set the standard for industrial spray finishing. Today, one can find Binks spray finishing technology at work in virtually every industry around the world.
Binks 98-3162 SV 100 HVLP 2 Quart Pressure Feed Spray Gun Outfit
A great outfit including a SV100 spray gun, 2 quart outfit, and hose. Everything you need for pressure fed spraying. In stock for same day service, no order minimum needed.
Tip sizes included: 1.1mm, 1.4mm
Devilbiss KB Two-Quart Pressure Cup KB-555 Aluminum (Tank only)
All KB-II style cups are pressure regulated and have a 2.4 quart (77 oz.) capacity. They are designed to be attached to any manual spray gun with air and material hose. The cup may be carried in one hand using the comfortable hand grip or left on the floor while spraying. The KB-II's wide diameter and low profile provides a low center of gravity which increases stability and resists tipping. Models KB-555 and KB-545-SS include a 0-30 psi gauge. KB II cups are supplied with KK5051 disposable cup liners (5 each) to reduce clean up time and cleaning solvent.
Binks 7041-6931-1 SV100 HVLP Pressure Feed Spray Gun
A great budget spray Gun option. The SV100 is HVLP compliant and requires10-14 CFM to spray effectively.
Small Volumes
Binks 2466-HV1 Trophy Gravity Fed Spray Gun Value Pack includes 1.2, 1.4, and 1.8 Fluid Nozzle
Binks Trophy HVLP Air Spray Gun Gravity Feed 1.2/1.4/1.8mm. The Binks Trophy HVLP Series Gravity Feed Spray Guns are designed to provide superior finishes in the wood finishing, automotive and industrial marketplace. The Trophy Series Spray Guns feature the rugged construction and dependability that you expect from the Binks brand. Our designers have emphasized ergonomics and optimized air flow through the guns to improve atomization for maximum transfer efficiency and finish quality. With the right Binks Trophy Series set up, you will be able to spray any material from stain to zinc.
IWATA LPH80-122G Compact HVLP Gravity Spray Gun - 1.2 MM w/ PCG2D1 150ml Aluminum Gravity Cup
- Spray pattern ranges from 1.6 inch round pattern to a full 5.5 inch fan pattern, making the LPH-80 perfect for coating small pieces, spot repair, blending, shading, and touch-ups
- Lightweight and compact, the LPH-80 is great for small surfaces and tight spaces that can be difficult with full size guns
- Using only 1.8 cfm at 13 psi, this low-air-consumption gun provides high atomization with precise control of the spray pattern with very little overspray
- Optional E4 air cap creates a wide, flat pattern with fine atomization
- Can be used with the 3M PPS System, 150 ml aluminum gravity feed cup or with a PC-18D pressure pot (using special fittings)
Final thoughts on spraying mold release
Spraying mold release is a fast and efficient way to apply mold release to ensure products don’t stick together. By understanding what type of spray equipment will be best for your mold release work, you can ensure efficiency and effectiveness.