Small update on the mechanics.
After some adventures with the main shaft some changes have been made to the mechanics. I will soon update the pdf but first I present them here.
Before all, a
big THANK YOU to Nicolas Jaunin for helping me with the fabrication of a new shaft. The old one had a flaw or got a hit without noticing it and the helicopter was vibrating like crazy.
With the new shaft there are practically no vibrations (other than the "normal" ones that every helicopter has). Nevertheless, I have decided to lower the headspeed from 1450rpm
down to
1300rpm. For that the easiest way was to remove 2 cells from the battery pack and use a
10S pack instead of a 12S (saved ~200g too! -
5.4Ah ThunderPower pack). In that case there are less stresses on the rotor head but I needed to modify the gear ratio for the tail rotor as well as the tail rotor blade size because the tail rotor lost quite a lot of its efficiency.
Fortunately, Align has what is needed for that thanks to its
T-Rex 800E model parts. So I have replaced the tail gear set and the blades with the following pieces:
HQ1150B (115 Carbon Fiber Tail Blade, T-Rex 800)
H70110 (T-Rex 700E 104T M1 Helical Autorot. Tail Drive Gear Set)
H70111 (T-Rex 700E Motor gear mount)
The latter (motor gear mount) is very important to change as the big white gear is bigger than the previous one and if you keep the old mount it will not fit (
it is well mentioned on Align's web site too).
So now the headspeed is really optimal and the tail rotor does it's job very well. The gyro gain is around
70%. It comes to my mind now that I have not published yet the settings of my
V-Stabi as well as those of my
Hitec Aurora-9. A big help for fine-tuning the headspeed and the pitch curve was the
J-Log2. The data recording feature from the
Kontronik Jive 80+ HV ESC and, most of all, the possibility to send that data to the Aurora-9 via telemetry have been most useful for the finetuning. I will post some plots this week to show the power consumption and the current flow through the Jive.
Cheers,
Hellenicopter.