Our Thermoplastic Process, step-by-step
Huntco's state-of-the-art Thermoplastic Coating is one step beyond our Powder Coat. Thermoplastic is designed for maximum mechanical performance, impact resistance and UV-stability. Because it is thicker than powder coating and it has a little bit of "give" to it, Thermoplastic is the most bike friendly finish on the market.
Our thermoplastic coating is a polyethylene copolymer-based powder, Polyarmor® G17 by Innotek®. It is environmentally safe, containing no PVCs, phthalates or chlorine components that can emit VOCs.
1. Pretreatment and Preheating
To help the polymer adhere to the metal surface of the rack, it is first sprayed with an alkaline pretreatment and then heated which preps the surface to receive the thermoplastic coating.
2. Powder Application
The heated racks are hung on a conductive wire and then sprayed with an electrically-charged thermoplastic powder (very much like the Powder Coating).
Thermoplastic powders are available in: Black, Dark Gray, Light Gray, Royal Blue, Sky Blue, Red, Yellow, White, Dark Brown and Hunter Green.
The coated racks are allowed to cool and checked for flaws in the coating. You can see below how the powder has flowed across the part evenly, but the surface is still quite rough.
One of the great properties of thermoplastic is that a coating is never wasted–if there is a flaw, the part can be reheated and the coating will reflow.
4. Post-Coating Finish Firing
Once the rack has cooled, it is heated again to complete the flow and leveling of the powder, creating new molecules that bind tightly together. This produces a dense, uniform coating. These Stirrup racks are on their way out of the kiln with a satiny semigloss finish and lightly stippled texture.
5. Ready to ship!
Although the finish is tough, we pack all of our racks with great care so they arrive at your site in perfect condition.