It has been quiet here recently. I thought I'd make some noise by shamelessly sharing my recent 3C project with you all. All comments/suggestions/criticisms will be deeply appreciated.
JR and ALIGN die hard fans might want to look away now as I introduce my "700E ASG"
This by no means is the very first attempt at marrying JR ASG head with ALIGN 700 series mechanic. Recalling as early as 2010 UK national, there was already a couple of 700N with then VibeSG head. They were at a corner of a picture and very little has been said about them.
So. I have been flying my VSG since its very release, it was meant to be a 3D machine but I was having a lot of trouble getting on top of my YS 91 SR-3C. Therefore, while trying to outsmart YS, I played with the head too. 3 years gone by and the YS is still untamed but I have pretty good understanding of the ASG head (several upgrades to bring it from VSG head to ASG head except the very expensive grips). When my ratio adjustment reflected correctly in flight, I knew I got it
Inspiration of my project
A stretched, electrified Vibe 50 that runs 12S swinging Radix FAI 710, every bit of a competitive FAI machine with whole lot of Kiwi ingenuity and ¡°can-do¡± attitude. Most of all, it is affordable and easy to find parts. It even has CY¡¯s approval.
After two rounds of FAI competition this year, I realised it is time to go electric as I seriously need to work on aerobatic components. With YS powered VSG, I would never get enough upstairs air time. Also, the release of 700E DFC fell nicely in place. 700E DFC was chosen mainly due to accessibility of parts. I am fortunately enough to know some good contact and being not so sure if this is going to work, I don't want to invest too much. On top of that, it is always easy to sell an ALIGN heli shall the project fail. Then the direct swash actuation makes it more configurable shall I need to raise or lower swash or use different swash.
Keeping things simple and wanted to retain the feel that I'd liked with VSG as much as possible, I first transplant everything swash up from VSG to 700E DFC
It looked workable but binding soon appear
That was -10¡ãpitch and 6+¡ãf&b. This is due to ALIGN swash has ball positions that are further away from the center, servo to swash and swash to head, compared with JR swash.
After digging deep into my drawer, this came out of the search
This is the VJ Product 12mm mixing base with 600 mixing arms with spacer nuts to have proper stand-off for the arms, otherwise phasing will be off and heli will fly funny.
Notice that ALIGN mixing base is wider than JR/VJProduct's. 700E mixing base cannot be used here as the phase pin is different size.
This is everything puting together with the spacer nut shown. Now the R arm lines up with center of mast.
Showing all the necessary parts:
JR ASG Rotor Head Assembly
JR/K&S/VJProduct 12mm Mixing Base
ALIGN 600 Mixing Arm
Thin 3mm nylon nuts (I shall be more specific about the height of it
ALIGN 700 FBL Mast
ALIGN FB Swash with DFC servo balls and 4 600 balls on the inner ring
Here is my delta and bell/hiller setup
With VJProduct FAI arm, the head spots correcting delta. It helps managing the wind a lot when required ratio is hit, when off, it is nevertheless rather confusing.
Bell/Hiller ratio looks and measured 1:1 but because of their positions away from spindle center their effect is not 1:1. Notice that the Hiller linkage ball does not have the stand off it suppose to have but now with Bell linkage ball. It felt very disconnected, flybar overpowering first flight after conversion, then a fellow 3C vetern reminded me to increase Bell input. So I moved the Bell linkage ball one hole towards the center but then heli drift with wind (flybar not powerful enough) and linkage binding happended at large -v pitch as Bell link got too close to seesaw. After gazing at the head for sometime (number of days of flying) I finally realised that I could put Bell ball position back to where it was and simply use the stand off on the Hiller ball to correct the balance.
Now it hovers better than VSG. It refuses to move when there is no input
. I have to max out travels to get +14¡ã ~ -10¡ã collective/7.5¡ãcyclics, swash menu values are in their high 70s. This yields max control resolution. With speed and torque of BL700H, I am not so worry about the servo travels. So far I am very impressed with BL700H, they respone to every single sub trim and in flight, trims do not seems to drift and the same amount of trim between modes of same type of maneuvour.
Hope you still awake and enjoy the read
. I now have an inexpensive 3C machine that I can fly and not worry about crashing it. Another beauty about this is now that 800 machines have been flew in 3C, I am only 1 pair of blades, 1 boom, 1 TT and 1 tail control CF tube away from try it out and that can happen next week