PATEL
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According to Lars Morvay, VP of Vehicle Engineering at Tesla on the Ride the Lightning Podcast today.
"You inject the polyurethane paint at the same time that you make the plastic panels. There's no paint shop with that vehicle. We put the colors in when we make the panels. That's it. If you want to repair it, it's just basically paint."
More details:
In sum, the Cybercab will use Polyurethane paint injection into its exterior plastic panels instead of paint, eliminating a complex, expensive & time consuming process, making the Cybercab cheaper & easier to build & likely repair.
This is a specialized manufacturing process often used to create durable, high-quality finishes on plastic components, such as automotive parts, consumer electronics, or industrial equipment. The process integrates painting directly into the molding stage, ensuring a seamless and robust finish.
First, the process begins with the creation of a mold, usually made from steel or aluminum, designed to match the exact shape and specifications of the desired plastic panel. This mold is precision-engineered to account for both the plastic substrate and the polyurethane paint layer.
Next, a polyurethane paint mixture is prepared. Polyurethane is chosen because it’s tough, resistant to scratches, chemicals, and UV light, and can be formulated in various colors and gloss levels. The paint is typically a two-component system, consisting of a polyol resin and an isocyanate hardener, which are mixed just before injection to start the curing reaction.
The plastic panel itself is formed using an injection molding machine. A thermoplastic material, like ABS, polycarbonate, or polypropylene, is heated until molten and injected into the mold under high pressure. This forms the base structure of the panel. After this initial injection, the mold may be slightly adjusted or a secondary cavity opened, depending on the specific technique being used.
Then comes the polyurethane paint injection. In a process often called in-mold coating (IMC), the polyurethane mixture is injected into the mold over the freshly molded plastic part. This happens while the plastic is still warm and semi-solid, allowing the paint to bond tightly with the surface. The injection is carefully controlled to ensure an even layer—usually just a thin coating, around 0.1 to 0.5 millimeters thick—spreads across the panel. The mold’s design helps the paint flow uniformly, avoiding defects like air bubbles or uneven coverage.
Once the polyurethane is injected, the mold is kept closed under pressure while the paint cures. The curing process is fast, often taking just a few minutes, because of the chemical reaction between the polyol and isocyanate. The heat from the mold and the plastic part accelerates this hardening, locking the paint into place as it forms a cross-linked polymer structure.
Finally, after curing, the mold opens, and the finished panel is ejected. The result is a plastic part with an integrated, durable polyurethane finish that doesn’t require additional painting steps. This method saves time, reduces handling, and ensures the paint adheres better than traditional post-molding spray painting, since it’s chemically and mechanically bonded during the molding process.
Variations exist depending on the application—like adjusting the paint’s viscosity or using multi-cavity molds for complex shapes—but the core idea is combining molding and painting into one efficient step. It’s a slick way to get strong, good-looking plastic panels straight out of the mold.
"You inject the polyurethane paint at the same time that you make the plastic panels. There's no paint shop with that vehicle. We put the colors in when we make the panels. That's it. If you want to repair it, it's just basically paint."
More details:
In sum, the Cybercab will use Polyurethane paint injection into its exterior plastic panels instead of paint, eliminating a complex, expensive & time consuming process, making the Cybercab cheaper & easier to build & likely repair.
This is a specialized manufacturing process often used to create durable, high-quality finishes on plastic components, such as automotive parts, consumer electronics, or industrial equipment. The process integrates painting directly into the molding stage, ensuring a seamless and robust finish.
First, the process begins with the creation of a mold, usually made from steel or aluminum, designed to match the exact shape and specifications of the desired plastic panel. This mold is precision-engineered to account for both the plastic substrate and the polyurethane paint layer.
Next, a polyurethane paint mixture is prepared. Polyurethane is chosen because it’s tough, resistant to scratches, chemicals, and UV light, and can be formulated in various colors and gloss levels. The paint is typically a two-component system, consisting of a polyol resin and an isocyanate hardener, which are mixed just before injection to start the curing reaction.
The plastic panel itself is formed using an injection molding machine. A thermoplastic material, like ABS, polycarbonate, or polypropylene, is heated until molten and injected into the mold under high pressure. This forms the base structure of the panel. After this initial injection, the mold may be slightly adjusted or a secondary cavity opened, depending on the specific technique being used.
Then comes the polyurethane paint injection. In a process often called in-mold coating (IMC), the polyurethane mixture is injected into the mold over the freshly molded plastic part. This happens while the plastic is still warm and semi-solid, allowing the paint to bond tightly with the surface. The injection is carefully controlled to ensure an even layer—usually just a thin coating, around 0.1 to 0.5 millimeters thick—spreads across the panel. The mold’s design helps the paint flow uniformly, avoiding defects like air bubbles or uneven coverage.
Once the polyurethane is injected, the mold is kept closed under pressure while the paint cures. The curing process is fast, often taking just a few minutes, because of the chemical reaction between the polyol and isocyanate. The heat from the mold and the plastic part accelerates this hardening, locking the paint into place as it forms a cross-linked polymer structure.
Finally, after curing, the mold opens, and the finished panel is ejected. The result is a plastic part with an integrated, durable polyurethane finish that doesn’t require additional painting steps. This method saves time, reduces handling, and ensures the paint adheres better than traditional post-molding spray painting, since it’s chemically and mechanically bonded during the molding process.
Variations exist depending on the application—like adjusting the paint’s viscosity or using multi-cavity molds for complex shapes—but the core idea is combining molding and painting into one efficient step. It’s a slick way to get strong, good-looking plastic panels straight out of the mold.
