# Static Spray (DD-051) > Powder coating is a 'dry paint'. Polymer resin, curatives, pigments and flow additives are melt-mixed, cooled and ground into a powder as fine as baking flour. In electrostatic spray deposition, the most common method, a spray gun charges the particles and an electric field pulls them onto a grounded part, where the charge holds them until the part goes into a curing oven. At about 325–450 °F (163–232 °C) the powder melts, flows and chemically cross-links into a tough finish. Because there's no solvent, the process virtually eliminates volatile organic compounds (VOCs), and overspray can be recovered for reuse. Grounding matters: the path from the part to ground must stay under one megohm. - Department: Tech (also Science) - First published: 2026-01-23 - Last updated: 2026-01-23 - Permalink: https://detailenjoyer.com/case/static-spray/ - Author: Marcus Easterling (DetailEnjoyer), The Detail Department ## Quick facts - **DD-051-F01**: Powder coating is held on by static electricity until a 325–450 °F oven melts and cross-links it into a hard finish. _(Write-up · Exhibit C (The oven does the rest))_ - **DD-051-F02**: Because powder coating uses no solvents, it virtually eliminates VOC emissions, and overspray can be reused. _(Write-up · Exhibit E (Cleaner than solvent paint))_ ## Write-up Static electricity holds this paint in place. Charged powder clings to a grounded part until an oven melts it into a hard shell. 1. **What the powder is**: Powder coatings combine polymer resins with curatives, pigments, leveling agents and flow modifiers. These are melt-mixed, cooled and ground into a uniform powder 'similar to baking flour'. 2. **Charge and ground**: In electrostatic spray deposition the gun charges the powder and the part is grounded, so the electric field pulls particles onto it. The deposited powder keeps its charge, which holds it in place. 3. **The oven does the rest**: The coating isn't finished until it's baked. In the curing oven the powder melts, flows over the part and cross-links into long molecular chains, usually at 325–450 °F (163–232 °C). 4. **Grounding matters**: Powder build-up on hangers or conveyors degrades the path to ground. The total resistance to ground must stay under one megohm, which is checked with a megohmmeter. 5. **Cleaner than solvent paint**: Powder is a dry process that eliminates solvents and virtually eliminates VOC emissions. Overspray can be collected and returned to the hopper for reuse. 6. **Not just metal**: Electrostatic spray is mostly used on metal, but powder can also coat plastics and MDF, or be applied by fluidized bed (dipping a preheated part into fluidized powder). ## Related case files - [Print Precision (DD-005)](https://detailenjoyer.com/case/print-precision/): Another way of putting material exactly where it's needed. - [Marangoni Motion (DD-024)](https://detailenjoyer.com/case/marangoni-motion/): More everyday physics of fluids and surfaces. - [Rapid Liquid Printing (RLP) (DD-013)](https://detailenjoyer.com/case/rapid-liquid-printing/): Another clever manufacturing process. - [Liquid Lights (DD-073)](https://detailenjoyer.com/case/liquid-lights/): Another case about electric charge at work: a spray gun charges powder and an electric field pulls it onto the part. - [Linking Up (DD-302)](https://detailenjoyer.com/case/linking-up/): I linked another use of electric charge - [HoloFans (DD-630)](https://detailenjoyer.com/case/holofans/): Another case about how a familiar technology really works - [Paint Removers (DD-642)](https://detailenjoyer.com/case/paint-removers/): How a tough coating goes on in the first place - [Shine Sublime (DD-696)](https://detailenjoyer.com/case/shine-sublime/): Another case about coatings and finishes ## Reel vs. record - **Confirmed from the frames**: the Reel shows electrostatic powder coating (captions at 0.8–2.4 s). A spray gun charges fine resin-and-pigment powder that's drawn to a grounded part. [Powder Coating Institute; EPA] - **Missing step**: the Reel stops at 'sticking evenly'. Until it's oven-cured at about 325–450 °F, the powder is held only by electrostatic charge. Heat melts and cross-links it into the durable finish. [Powder Coating Institute; P2 InfoHouse] - **Too narrow**: 'metal and other conductive surfaces.' Powder can also coat plastics and MDF, and flame spray works on wood and rubber. [Powder Coating Institute; P2 InfoHouse] - **Simplified**: 'resin and pigment' leaves out the curatives, leveling agents and flow modifiers that make the film form. [Powder Coating Institute] - **Context the Reel skips**: powder contains no solvents, so it virtually eliminates VOCs, and overspray can be reclaimed. [P2 InfoHouse; Powder Coating Institute] ## Video: Static Spray: Static Electricity Holds This Paint in Place - Duration: 19.6 s · Published: 2026-01-23 - File: https://detailenjoyer.com/assets/videos/DT3kneqgVUb.mp4 ### Transcript DID YOU KNOW? Electrostatic powder coating is a finishing process used to apply a durable, uniform coating to metal and other conductive surfaces. In this method fine powder particles, usually made of resin and pigment, are given an electrostatic charge as they are sprayed onto the grounded object. The charged powder is attracted to the surface, sticking evenly on complex shapes. NOW YOU KNOW! ## Questions & answers **Q: What holds powder on the part before curing?** A: Charged powder is attracted to the grounded part and stays put. _(Source: Write-up · Exhibit B (Charge and ground) · What is Powder Coating? (Powder Coating Institute); Powder Coating Painting System (Pollution Prevention InfoHouse); Powder Coat Applications Final Report (U.S. EPA))_ **Q: What turns the loose powder into a hard coating?** A: It's baked at about 325–450 °F, where it melts and cross-links. _(Source: Write-up · Exhibit C (The oven does the rest) · What is Powder Coating? (Powder Coating Institute); Sustainability: VOC Elimination (Powder Coating Institute); Powder Coat Applications Final Report (U.S. EPA))_ **Q: Why is powder coating low in VOCs?** A: It's a dry process. _(Source: Write-up · Exhibit E (Cleaner than solvent paint) · Sustainability: VOC Elimination (Powder Coating Institute); Powder Coating Painting System (Pollution Prevention InfoHouse); Powder Coat Applications Final Report (U.S. EPA))_ **Q: What must the part being coated be?** A: Resistance to ground must stay under one megohm. _(Source: Write-up · Exhibit D (Grounding matters) · Powder Coating FAQ (Powder Coating Institute))_ **Q: Which can be powder coated besides metal?** A: Electrostatic spray is mostly used on metal, but other substrates work too. _(Source: Write-up · Exhibit F (Not just metal) · What is Powder Coating? (Powder Coating Institute); Powder Coating Painting System (Pollution Prevention InfoHouse))_ ## Sources - [What is Powder Coating? (Powder Coating Institute)](https://www.powdercoating.org/page/whatispc) - [Powder Coating FAQ (Powder Coating Institute)](https://www.powdercoating.org/page/FAQ) - [Sustainability: VOC Elimination (Powder Coating Institute)](https://www.powdercoating.org/page/Sustainability-Lifecycle) - [Powder Coating Painting System (Pollution Prevention InfoHouse)](https://p2infohouse.org/ref/06/05086.htm) - [Powder Coat Applications Final Report (U.S. EPA)](https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10120TC.TXT) ## Cite this case file Easterling, Marcus. "Static Spray." The Detail Department (DetailEnjoyer), case file DD-051, last updated Jan 23, 2026. https://detailenjoyer.com/case/static-spray/