This is an optional KDE Direct 115 Tooth, Mod 1 pitch, HD Main Drive Gear. This gear is intended for use with the Align T-Rex 700E and 700N E-Conversion series helicopters, and replaces stock Align part AGNHN7019A. The Heavy-Duty series Main Drive Gear is precision CNC-machined from a proprietary Nylatron MoS2-Filled Type 66 Polyamide, one of the best materials available today for polymer gears and the perfect match for an extremely strong, smooth running, and durable power transmission for the TREX 700E series helicopters. The gear is composed of 115 teeth, utilizing the metric MOD1.0 tooth standard for incredible strength.
Through months of testing, the gear has been optimized to include numerous design features for optimum performance, including:
Important Notice: Due to tolerance variability with the stock TREX 700E setup (non-adjustable motor mount), there are instances when the install will exhibit an excessively tight mesh with the pinion using the KDE Direct Main Drive Gear upgrade. Thus far, approximately 1-2% of stock TREX 700E kits exhibit this issue and in these instances, it is recommended to also install the KDE Direct TREX 700E Universal Motor Mount and Pinion Support upgrade to provide optimal gear mesh adjustability.
- Increased gear height to 12mm (stock is 10mm) for increased strength and contact surface area.
- The tooth involute profile has been optimized through numerous design iterations for increased tooth engagement and strength, providing an incredibly quiet and durable gear for a MOD1.0 power train.
- Weight was reduced through FEA optimizations of the machining pattern to significantly reduce weight, while maintaining full strength of a solid-gear profile.
- The self-lubricating properties of the proprietary MoS2-Filled Type 66 Polyamide material provides exceptional wear and noise properties, providing a gear that can withstand the harsh nature of hardcore 3D flight.
Design Advantages Compared to standard Acetyl (POM) Resin Gears:
- Density: 1.15 g/cc - Weight reduced by 19% (55g FEA optimized for maximum strength and minimum weight)
- Tensile Strength: 12,500 psi - 32% Stronger tooth for more power and torque capability
- Shear Strength: 10,500 psi - 32% Stronger tooth root for more power and torque capability
- Flexural Yield Strength: 17,000 psi - 42% Stronger tooth root for more power and torque capability
- Coefficient of Friction: 0.200 - 20% Less friction for less noise and more power transfer
- K (wear) Factor: 90e-10 - 55% Less wear for a longer lasting gear
NOTE: This gear is not recommended for the TREX 700N or TREX 550/600 series helicopters. The reduced-height version of the gear (KDE Direct TREX 700 Series Main Drive Gear, 115T, MOD 1.0) is recommended for those setups to achieve optimal fit and performance.