Here is a tool I made to hold the stator when re-winding micro-sized brushless outrunner motors like the HP series (HP08, HP08-2, HP06, HP07). Materials used is a M5 threaded rod, M5 nut, and two pieces of a brass tube (5mmx6mm). The handle is from an old paint roll.
I rewound the HP08-2 with a winding scheme originally posted by Terry74 (thanks Jay!). Its 2 strands of 30 AWG (0.255mm) magnet wire, 5 turns, delta. Lots of detailed information on winding schemes and diy brushless motors can be found at the great website powercroco.de. Very good magnet wire can be found at Brocotts UK (search eBay).
For the record: Original winding of my HP08-2 bought from WOW Hobbies was 3 strands of appr. 0.2mm, 5 turns delta.
finally it’s flying…
Walkera 2609 RX (from 4G6 Heli), Walkera 2801Pro TX, using PROGMIX for differential thrust, AP02 Outrunner Motors, XP 3A ESCs, proportional actuator mod elevator, 240mAh or 400mAh 20C Zippy, AUW 30gm (240mAh), AUW 34gm (400mAh)
Some impressions:
After all, it’s still an X-Twin Acrobat/Rolling Fury, it feels pretty similar to the stock version. Stability from the dihedral is still there but a bit lower (due to higher weight i guess).
What’s really great is that there is no more slow reaction or range issues. Also the roll-rate is much higher, i can really turn/roll it from side to side in no time. Still playing around with the mixcurve though. At first it was way to nervous around midstick aileron i.e. rolling like crazy. I’ve flattened the curve near midstick and thats much better.
Also it is much faster due to higher weight an the brushless motors.
I’ve put some tape on the props to get more thrust and this worked, static thrust of the plane is now near 30g with fresh lipo. I was getting about 20g static with one motor alone on my testbed – don’t know what happend. Even with a 1s 850mah Zippy only 30g for the plane.
Today was mostly calm but with some nasty gusts so not the perfect conditions, im really looking forward to fly it under perfect condition. Indoor is not an option because its way to fast (3-court gym wouldnt even be big enough i guess).
Little problem with the bl setup is that the motors / esc sometimes cut off on startup, i.e. i have to avoid pulling throttle down too far because the ESCs take about a second to initialize and start up the motors again – this second will often result in a crash.
It seems that i have gotten one bad motor that does this cutoff on startup more often, maybe ill replace that one. Or its the 3A ESCs that are to weak.
The elevator actuator seems to be at it’s limit with this setup. Not enough torque. I’ve tried to make the elevator area bigger with some tape but then the actuator cannot pull the elevator all the way due to the airflow from the props. So maybe i’ll go for a 1.5g Spektrum servo.
Whats really great is that the thing still has mad power with 34g AUW (400mAh Zippy).
To sum it up, the RX/TX with mixing option, super fast reaction and no range issues is the best part, the BL motors performance and cutoffs are not quite perfect yet. Overall its still an acrobat / fury and i like the mod for that.
First step towards building a brushless direct drive 2.4Ghz gyro-ed PizooZ. The shaft of the HP03T 2.9 BL outrunner was replaced by a 50mm 1.5mm shaft that holds the picooZ main rotor. The picooZ rotor head was drilled to 1.5mm (stock is 1mm). The HP03T is normally used for the Walkera 4#3B brushless tail conversion. The motor is power by the flea converter.
Thrust at mid-stick is about 20g – about right, remains to be seen if the revomix works out.
I’m aiming for about 15g AUW for the 2Ch – if it works as planned this will be the platform for the acutator cyclics mod (see post here).
RC Groups User marc31 just presented the first brushless conversion of the PicooZ. The mod is based on the 2.4 GHz Walkera 4#3B 4-1. The cyclics are controlled by actuators.
