AM32 Power for Serious Weapon Builds The FingerTech BL40A AM32 ESC is a 40A brushless speed controller built for beetleweight combat robots. Running FingerTech’s own customized AM32 firmware, it delivers faster spin-ups, better low-end torque, and more efficient power delivery than BLHeli equivalents. If you’re driving a high-demand weapon motor and need an ESC that can keep up, this is it. Why AM32? AM32 is a modern open-source firmware platform designed specifically for brushless motor control. FingerTech has taken AM32 and tuned it for combat robotics — optimizing spin-up routines and low-end response for the demands of weapon systems. The result is an ESC that responds faster and more predictably than the BL20A BLHeli ESC it replaces, with twice the current capacity for larger, more demanding weapon motors. Compatible Motors The BL40A is the recommended ESC for FingerTech’s primary beetleweight weapon motors. Pair it with the F4006 740KV Brushless Outrunner for the NightWing undercutter weapon system, or drive the S2838 2970KV Brushless Inrunner for beater bar and similar weapon configurations. Both motors demand more current than smaller ESCs can reliably deliver — the BL40A handles them without breaking a sweat. Drive Motor Use Need a single-direction drive ESC for a high-power brushless drive system? The BL40A works here too, though most beetleweight drive applications will want the reversing version instead. For reversible weapon direction or brushless drive, see the FingerTech BL40A AM32 Reversing ESC. Wiring Notes The BL40A has no onboard BEC — you’ll need a dedicated 5V BEC to power your receiver. Connect the three motor wires in any order; if the motor spins backwards, swap any two wires. The NightWing kit uses this ESC paired with the NightWing Electronics Kit — all wiring is documented in the NightWing build instructions. Drive with Mega Spark Running a brushless drive system? The BL40A pairs well with FingerTech‘s Mega Spark Brushless Gearmotors — available in 750KV, 1500KV, and 2300KV variants. For drive applications you’ll want the reversing version of this ESC.
