Coyote`s Skywalker

[Coyote]

Hi guys, well eventually it came, another plane ! Whoop whoop.

Heres the build log for my V3 Skywalker.

Now loads already have Skywalkers, there are plenty of really good in depth builds on here like Bignose13`s Skywalker build log so i dont see any real point in going into it too in depth. Simons build is really well put together and great for reference. I like it that much his recommendation got me to wanting a Skywalker, then after seeing Pauls i knew it was heads above the Easystars capabilities.

So here`s a brief account of my build. I received yesterday and spent around 3 hours fitting gear to it. This didn`t include fault finding which i spart and parcel of building, but its all complete and working apart from vtx and Camera.

Anyway, i wanted to do this build a bit different, firstly ill be using a two lipo system, 1 for video, the other for motor. Its a first for me, im always normally using a single lipo system. I wanted to try this way round to see if i can get every single bit of potential interfeence out of my video. The second difference are my audio and video leads. The best way to reduce interference is by using phono or RCA leads. The reason we have them in our homes and on our FPV receivers is just for a clean signal. So all my audio and video wires are made in coaxial wire.

The Spec :

Plane : Skywalker V3
Motor : Turnigy TR3536-1100kv
Prop : 9x6
Lipos : 5000 mah motor lipo, 2200 mah video lipo ( both Zippy Flightmax )
ESC : Turnigy Plush 60 Amp
Bec : Turnigy 5a

Camera : Security Camera 2000 600 WRD OSD 600 tvl
Vtx : Bevrc 5.8ghz
Rx : RC305 ( Range video version )
OSD : Dragon Labs DOSD

Control : 459 UHF FSHH

Skipping all the lets get it out the box and have a look stuff, i was pretty impressed with the packaging, the skywalker fuse came untouched, wings were fine but the canopy was damaged. Not a problem for me because i am not using it anyway. The extra carbon on the wings in the V3 is good, but personally i would have liked them longer. The flaps being moved to help strength was a good move. I will strengthen it up a bit more tomorrow but ive done a few thing today to just make it that bit better.

Anyway, onto the install, first to go in was my UHF rx, being at the rear of the compartment meant adequate spacing between a GoPro up front shouldnt be an issue. Once loacted, i then added the DOSD next to it for ease and clutter free wiring. At this point i also added the Bec :



I had several options with the flexible Skywalkers layout of positioning the GPS. The tail was an option, but i felt it left the upgraded sensor exposed a bit. I could also have it on the canopy base, but this means plugging and unplugging which we really want to avoid as the GPS data can make the difference between a plane comming back or not, especially with RTH.

So i decided to use the Skywalkers recommended postition for the pan camera. Im not putting the camera there, i see no advantage over having it on the canopy base, but if its where they recommend its exposed if the plane ever flips over.On the canopy base the camera wont make contact in these situations so no damage. No damage, happy Ian :)

The camera location that the GPS is going into has a section below cut for the camera pan servo, this is ideal for the ferrite ring for the GPS sensor that enables it to lock sats quicker. The way its mounted below, the GPS is very well protected, no carbon, metal etc is blocking its view and to me is ideal for its functionallity







Next i added the Curet Sensor for the DOSD, this is the only connection ( ground ) between my video and motor circuit. This means absolutly no groundloops for the Esc`s current to flow. It does however give the Esc`s speed control signal a ground reference. The current sensor then is the only part that can transmit any interference to the video side. So i added a frerrite ring to the wire. I then ran the cable so its physically seperated from any of the systems other wires.



I then began the wiring looms, to join the UHF to the DOSD, its working through a single ppm stream. I recently made a little circuit board for isolating the negative rail of the DOSD which has been causing some grief recently. I didnt really need it on board but i thought i`d fit it anyway to show it working :





I positioned this then started adding the interconnecting wires, then i made an end off for the video lipo to link the system up



Next up was the video wires. I used some premade RCA leads, cut them down and made a 4 pin connector for the DOSD.

What this means is at any point i can plug unplug various cameras, goggles and telemetry as i want. I then made the leads with RCA plugs to Vtx end and installed that too



My wires run the way they do to avoid running next to each other, video is seperate from servos, which are seperate from gps and the likes :



Down the tail end, the UHF antenna was fitted, the two servos and the wire ran through the carbon rod :



On the other side of the tail i cut a square out of the rear :



The Turnigy TR3536 was fitted, along with the power cable for the motor lipo, i left the wire free running so if i wanted to plug in a Watt meter i have plenty of play



With the prop on everything was tested while it was accessable, handy really as it didnt go smoothly lol



I cant really make the camera pod yet untill the camera arrives so i just fitted the premade wires, power for camera and RCA lead. Simple two plugs and its ready :)



I cut the hatch and fitted the hatch catch kindly supplied by Paul ( PK-Surfing )



When the sides get glued together, the square i cut out of the tail now acts as an access hatch for easily swapping servos over without damaging it



Strength wise, im going to cover it with tights and paint with waterbased varnish, this will make a form of fibre skin over the fuse making it much more knock resistant. Other than that ive added two strengthening rods, one on the bottom based :



The other in the tail section, one each fuse side as the tail seems especially weak to me



I also dont like the hinges at all, so all surfaces have been cut and taped, i did this to the rudder so the tapes inside the tail and glued for maximum strength



Just the Camera, vtx and its ready for its CG doing and its maiden :)

All DOSD functions checked and working fine, looking forward to this one

[pk-surfing]

Blimey, you put that together quicker than a Quickfit fitter !

Nice and neat wiring, the use of the coax cables for the video must have a big benefit for the signal can't wait to see how it works out, the GPS fits so well its almost as though it was made to go there.

I think there might be a window of opportunity for the wind dropping Fri mid afternoon !

PK

[sheep600fx]

Very nicely done mate, As tidy and well thought out as Ive come to expect from you lol, Look forward to seeing the maiden

[g.collins]

Looking good mate, nice looking platform, Have you got loads of FPV plans, or do you keep recycling the parts, lol :)

[Coyote]

Cheers Sean, i`ve been planning the wiring for ages lol

Lol Gordon, the Radian died a death, but i will be getting another, as far as relaxed simplicity goes its hard to beat. The Asw`s still waiting, im in no rush with that yet. The Easystar, well i was not impressed by it, the Skywalkers to replace that and i have the stealthwing too.

So that should be it, a large glider, smaller foamy glider, skywalker and a Stealthwing should do me :)

[bignose13]

Very nice ian, one of the cleanest installs i've seen on a skywalker, looking forward to seeing this baby fly and really hope you have more luck with this than you've had in the last couple, i'm sure your gonna love it

[g.collins]

oo don't say that,lol I haven't even got the Easy Star up yet, I'm sure it will do me for a wile, I'm already looking at the Sky walker and wondering wot if, :laugh: I have ordered some 1 cell light stuff to fit in some micro plane or helly, I just boult the Blade 120SR, it would be fun to fit it to that.
I'm fed up with waiting for the Dragon Link to come, for the Esey Star so I glued the fuselage together lased knit, and Im fiting 35Mhz, I'm on holiday next week, but when I get back I won't it finished, maybe in time fore the bounc meeting in June.
regards Gordon

[n00b@FPV]

what meeting in june
link please :)

[mark1975]

Very very nice but blimey its big lol ..ian with regards to mounting the uhf antenna vertical how have you done this to avoid belly landings ..

[Coyote]

Yes she`s a whopper, the tail is raised at the back so the antenna just folds but never gets trapped on landing

[g.collins]

what meeting in june
link please :)

25-26 June 2011 in oxfordshire, go to home and look at events.
regards :)

[Coyote]

Just bits and bobs to do today. I strapped the wings with re-inforced tape to strengthen no end. The camera wont pick it up so ive left them photos for now.

I cut two airflow slots for the ESC cooling :



I fitted the 25mw 5.8ghz Vtx, man its tiny :



I would say, seeing its been thought out for FPV and even a flat base for the Vtx to sit on, why oh why did they decide to put it there and not further down baffles me. For the sake of a few cm it would have been much safer. With the original prop holder on the swining 9x6`s tip was mere mm away from the vtx cable exit. I put a shorter version holder on so if there is any tail flx there will be no nasty suprise video loss :)

I used a dummy weight for the camera and set about marking up the lipo positions for the CG. Ive gone for a 30mm back from servo slot CG as this seems to give the best glide and neutral on throttle.

Once the lipo positions were marked i then glued some depron in. One reason was easy location, if the battery fits, thats where it wants to be :



The second reason is best shown on the picture below. After a fair few unplanned landings, the one thing ive learnt is a lipo has a huge ammount of energy on impact and can make quite a mess of a nose. The strip below serves two purposes. First as above is locating the lipo, the second is a crumple zone. The idea being in a nose impact, the energy of the lipo will be reduced by the sacrificial foam strip, breaking it, but hopefully loosing a lot of its potential before getting to the nose.



Its narow to let the cooling air though, but glued enough to give under impact but cusion the blow

The same for the video lipo in the rear, an energy absorbing zone so it doesnt slam into the larger battery ( hopefully ) :) :



The Autopilot and everything has now been tested and fully operational, so its just the camera and its ready for the maiden.

[mark1975]

Gl with the maiden ian ..she sure looks almost  ready..

[WSWhitby]

Looks good to me but where do you get your Female free Coax sockets from, I mean on the end of cable not fixed not at no cost, .
Weather today  on the East Coast a little calmer so we all may get some flying in hope so I am suffering from LOS withdrawal symptoms and FPV first time  :-\ gitters.

Regards

John

[Coyote]

Hi John, i couldn`t source any of the femailes in the type i wanted without coax so i got these cables and cut the ends and just made the bare ends off instead

http://cgi.ebay.co.uk/2-Metre-3-RCA-Male-3-RCA-female-Audio-Lead-AV-UK-/200561508321?pt=UK_Computing_CablesConnectors_RL&hash=item2eb265bfe1