AH-6Z Littlebird Night-Ops build project

[Zeeflyboy]

So a little tail modding and it's looking good!

As I wanted to use the tail box I already have, I knew this new tail wouldn't be a direct fit. First thing to solve was that the grub screw didn't locate well on the tail shaft flat, so the option was either to grind a new flat or cut a couple of mm off the end of the shaft. Given the tail sits quite far out already and travel shouldn't be an issue I decided to shave a couple of mm off the shaft.




The next bigger problem is that the old tail's slider was a bigger diameter and also had the ball positioned at the back. I came up with this little mod using a small piece of aluminium to both space the ball backwards and also make up the gap from the new smaller diameter slider. Thankfully it worked beautifully! Now with the pitch slider arm at centre I have a few degrees of positive pitch on the tail blades to oppose the torque at neutral, and everything moves smoothly with no binding.




Now I just need to fit the head and measure up for some turnbuckles...

[Zeeflyboy]

Fitted the head and measured up - I need some 40mm turnbuckles. Ordered those, so now it's back to waiting.... suppose I had better get on with some other stuff in the mean time lol. I will at some point drill the main shaft with a new jesus bolt hole, that will allow the head to drop down about 1cm which will look a bit better. Have to wait until I'm next with the CNC machine for that though so not going to let it stop me in the mean time.








Oh and yeah I fixed the Taranis - had a 3 position switch in my parts box that fits so I just installed that. Looks like the Futaba Short style switch will be a better long term replacement so ordered one of those too.

[Gundummy]

fantastic  ;D ....

Looking forward to see how the vacu-forming goes.

GD

[Zeeflyboy]

me too!


So my nice little turnbuckles arrived, fitted them just now




At some point I think I'll paint the swash timing clamp and the central section of the head black, as much as I like the shiny bling bling it's not really fitting on this heli!


I spent most of today getting to grips with the Taranis... Think I've got it operating as required but won't know for sure until I try to run through setup on the Naza. Coming originally from Spektrum and more recently Futaba and Jeti, I have to say I didn't find the Taranis completely straightforward... just about got the hang of most bits now though.

Anyway, needed to start modding it of course - First to mount the EzUHF I just took the stock blank module cover and printed out a little retainer to allow me to bolt the EzUHF cradle to it. It now just clips into the module back - very quick and easy.




Next up to fit correctly I had to remove the grab handle - which left me with an interesting place to put my missiles and miniguns switches with just a little plastic carving inside. You may also be able to see the small connector to the left of the EzUHF - this is a neat little 3 pin bayonnet style locking connector which will provide the PPM, PWR,GND for the EzUHF. I'll be using the module bay itself to install the Channel wizard... In total I added the two red switches, a small 2 position toggle on the back for camera selection, and a 6 position switch on the left shoulder for lighting control, all of which will go into the Channel wizard.

[Zeeflyboy]

So I've had a bit of a change of heart as regards the low voltage power system in the heli, and I've decided to run almost everything from a single BEC with battery backup and run a very small separate 3S lipo for the Miniguns and Missiles.

My thinking is this approach greatly reduces the complexity of the wiring, and saves adding another noise generating BEC into the mix. By offloading the minguns and missiles I take away a noise source (minigun motors) and a potential huge current spike (missile ignition), and can run them at a higher voltage.

Now this does mean that I'll be running 4 big servos (cyclics + Tail), Naza + GPS, OSD + GPS, 2 cameras, 7 auxiliary function servos, 2 screens, various small LEDs and the three big 1 Watt Landing lights from a single BEC. It needs to be up to the job.

I have come across this, which has a trifling 40A continuous and 50A peak with an adjustable output voltage from 5.6-10v... it also seems to have a backup system though I'm currently looking into that a bit further. Now that is a BEC worthy of using methinks...

http://www.modeltec.ch/de/BEC-Pufferschaltung/HV-BEC/Rprototyping-HVBEC-ALU

[dogzilla]

Now that looks proper.

Jeti also do some nice BEC's like this, dunno if it would meet your needs but it has 2 inputs :

http://www.jetimodel.com/en/katalog/Accessories/BEC-Regulators-Switches/@produkt/SBEC-40/

[Zeeflyboy]

I've given jeti enough money lately with the DS-16 and the Mezon 130A ESC I bought this month lol...

That is a pretty chunky ESC, and in reality would probably be fine, but where that is around 18A costant and 40A peak the R2 is 40A constant. Ok it's total overkill and would probably melt the servo connectors, but I loves me a good overhead.

[Zeeflyboy]

So I ordered that BEC... cannae wait

Thought I'd just share these pics after I did a test fit for the tail and head - starting to look like a heli! Wooo! I'm trying to figure out the best way to come up with a single connection between heli mechanics and fuselage, Currently I'm thinking a 12 pin locking connector panel mounted into the floor. I also tested plugging in the LED and GPS plugs into the Naza as the mechanics are slid in and while a bit fiddly, it works fine thankfully. I apologise for the messy work table btw, don't tell the GF please.

The eagle eyed among you may notice how the registration and the U.S. Army don't match - unfortunately when I got the replacement registration decals they were cut from the wrong material - I should have the correct ones on the way at which point they'll be clear coated and weathered to match, so don't panic I'm not leaving it like that lol

[Ratty]

This is jut too sick. I cant wait to see it finished. Keep up the good work.  ;D

Any idea how many hours you've put into it? I wont even ask about how much £££.  :P

[Zeeflyboy]

 :laugh:

Honestly I couldn't tell you either figure... Too hard to say. I can say I've almost been doing this a year since my gf bought me the fuselage for my birthday last year which is the 26th September.

Mental

[Jameskibler]

Bottom right of the last picture, are they model rocket fuel/engine sticks?

[dogzilla]

Bottom right of the last picture, are they model rocket fuel/engine sticks?

Yeah he is gonna have live este's type rockets shooting out the front.

[Jameskibler]

Jheeezze! This project is on a whole other level

[Zeeflyboy]

what... noo... those are simply for disposing of old lipos. Strap a couple to any old puffed lipo you have lying around, point at 45 degrees and ignite - now that old lipo is someone else's problem.



I think I may have ordered too much plastic lol... Two sheets of this stuff which I proceeded to cut down into 340x440mm sections for the vacuum former. It's 0.5mm PETG sheet and it is beautifully clear. Instructions say it's thermoform-able between 120-160 degrees centigrade, so a nice wide temperature window and easily achieved in an oven... we'll see how it goes.









My HV2 super duper mental BEC arrived today, looks really nice. It's a little smaller than I was expecting, which is a good thing. Not too heavy either... here it is next to the "old" gryphon BEC. Zee Germans are starting to make a real big contribution to this project - Mictronics lovely little rssi board and fractal antennas, Beautful SK-rotorkopf head and tail, and now the r2prototyping HV2 BEC.



jah

So I thought I'd make up a quick test missile just to see how the proportions look, so I ran out some fins on my printer and quickly put it together.








I also fitted my BEC (though I need another toroid for the second set of power wires) and also the first of my two mechanics-fuselage locking connectors. This one carries the 4 wires for the OSD-eLogger connector and also the RSSI/LQ from the mictronics convertor. The second one will carry PPM and power, plus audio from the antenna tracker module... both will plug into the fuselage just in front of the mechanics where the wires will then be distributed to the fuselage installed parts. The only additional connections to make will be the vTX filtered 6S feed, and the GPS/LED plugs at the back of the naza.

[Zeeflyboy]

And here I shall highlight the joys of owning a 3D printer lol...

So you need to make a mount for the connectors. Take some measurements and whip up a little design in about 5 mins....




Prep the file and put it on an SD card, plug it into the printer... 11 minutes later the bracket has been born.




I mean seriously, the future is here lol. It's just awesome.... here's the end product:








Oh and because it always seems to look different with the front on, here's a pic with the test missile for scale purposes. I made them just a little smaller than 1/6 (about 1/7) since the heli is itself somewhere inbetween the two... think they'll look pretty good.