Armor uses an older style slitting machine to manufacture TTR ribbon with specific customer requirements. It is generally run 8 hours a day, 5 days a week. The machine uses a gear that is constantly being engaged and disengaged with another gear. This gear is machined out of Polymer called Nylatron for its abrasion and impact resistance. These gears are replaced about every 6 months. Minimum order quantities for machining make it so that multiple years’ worth of parts must be ordered to bring the cost down to $100 a piece.
The goal of this application is 3D print the gear using Kimya PEKK-A so that it can be manufactured as needed instead of in batches, and to extend the usable life of the part.
The gear undergoes significant wear over time through being engaged and disengaged. It also spins at a high rate of speed which leads to repeated heat exposure from friction.
Cost to machine: $100 a part (with an order quantity of 20)
Cost to 3D Print: $44 (based on MSRP of PEKK-A)
A PEKK-A gear was printed with 4 shells at a 60% infill ratio. No design modifications were made. The gear was installed in the machine on 5-11-21. So far it shows very little signs of wear and has not impacted performance.