A large stator high Kv powerhouse motor from 3B-R (BBB)
Check out the full list of motors in this series here
Published: Jun 7, 2018
BBB or 3B-R, depending on how you read it, came on the scene last year with some really beautiful designs, and this latest offering from them is no exception. The machining and finish work more than lives up to their previous offerings, improving on the design in several areas. Aside from the stator size, this design integrates a few innovative features that are rare even in today's prolific motor market. The usual features are present here: a Titanium alloy shaft, 16x16mm mount oapatte and open base design, insanely tight air gap, and strong arc magnets. The real interest features are on the bottom of the motor. The most innovative is a 5mm internal shaft that comes with both a circle clip and an optional 3mm retention bolt. This leaves it up to the user as to their preferred method for shaft retention. The bolt is a full M3 alloy steel bolt with a 2mm hex drive. The second interesting bit on the bottom is a thin sheet of nylon plastic between the screw holes and the stators. This provides some protection from motor bolts impacting the windings if the wrong length is used. The weight comes in at just over 34g, which is quite respectable for such a large stator. My only concern with this motor is the lack of a magnet retention lip. On a high torque and high Kv motor, the retention lip becomes particularly critical to avoid slipped magnets, as these conditions put even the best glues to under significant pressure. Overall some interesting features and visually striking motor from 3B-R.
This motor follows in the footsteps of a series of dramatically powerful high Kv motors to hit the bench and gives them all a run for their money. The Kv here tested a bit above the stated Kv, coming in at 2660kv. The efficiency and thrust numbers are close to the similar Kv F60 Pro II 2700kv, breaking hitting 1500g at a 37A on the Lumenier 5x4.5 dual blade, and reaching just past 1700g on the HQ 5x4.5x3 v1s.