FPV HUB

Hi guys

Ok so after bashing up my prev skyfun I'm building another one. I'm using it as a trial run before I sink some more expensive kit into my partly build Z3. I'm not known for my clean or professional builds so I'm going to try and keep this tidy. And reliable. Hopefully.

Old skyfun/tek sumo hybrid- knackered. Rx and vid tv removed

http://tinypic.com/r/2ziwmqg/8 (http://tinypic.com/r/2ziwmqg/8)

It was a complete mess but flew surprisingly well despite being very asymmetrical. It was the second plane I ever bought so took quite a hammering as I learnt. I moved onto some easier planes for fpv (bixler, tek sumo and a big wing) before coming back to it to try and get a few more flights from it when everything else was out of action. It was also running a low powered 1000kv motor and a 10x5 prop- it was too big really and not that fast. Drew 20A on a 3s and managed about 35mph. Top speed was mid-late 50s with the wind and losing altitude.

It also suffered from quite a few lines in the video- despite using a LC filter. This is apparently because the video cable passed too close to the main power cables from the battery. It may also have been because I powered the 12V stuff directly from the lipo.

Anyway-

New skyfun for £35 from HK :D

I'm running a NTM Propdrive 2836 2200kv motor and will start with a 6x4 prop on a 4s.

So I need a 12V bec for the video Tx and board cam. Got a sony 600 to try.
5V bec for the servos
Hextronic MG14 servos
FY31 autopilot with
Ezuhf 4 channel lite Rx. Will try and set PPM up on it- although it's the first attempt.

Everything glued together with parts in position (except fy31). Gluing was a doddle tbh with 1hr epoxy. Why does it go off so quick? After about 30mins it gets hot and goes off within a few mins.

http://i61.tinypic.com/15i1bva.jpg (http://i61.tinypic.com/15i1bva.jpg)

Jobs (and questions for those in the know please :) )

I may as well fit some balsa elevons from the outset. The prev ones were knackered on my last one. What size do I need? Or should I just buy normal ones and thin them out a bit?

I want to fit my mobius to the very front so it gets a perfect view. I don't mind if the board cam gets a slightly restricted view. I suppose this means chopping into the nose a fair bit. Seems a shame on such a new plane but I don't want to ruin the aero.

I want to run it with a 3000mah 4 cell. Am I being too optimistic with this? I ruined my Tek Sumo chasing this goal......and I don't want to ruin it's glide slope or have a very high stall speed? I'm a bit afraid the C of G will be way too far forwards with such a big batt, two cameras and the autopilot all in front of the C of G.

I want to move the servos to the top- given the chance of this being nose heavy perhaps I should keep them fairly far back?

How much separation should I try to have between the video tx and Rx? I know people put a lot of emphasis on this- and it's easy to manage on a big wing- but does putting things right on the end of the wings potentially ruin the handling?

Should I fit some end tips to try and increase low speed life and stop air slipping off the end of the wing? I don't really understand why this isn't standard? It is on many wings......?

Really not looking forward to wiring all this- it's the most complex build I have done (first autopilot) and it's on a pretty small plane.

Anyway- will update the thread as I go. Thanks.

QuoteI may as well fit some balsa elevons from the outset. The prev ones were knackered on my last one. What size do I need? Or should I just buy normal ones and thin them out a bit?

I trimmed down a larger set I got from my lhs.

QuoteI want to fit my mobius to the very front so it gets a perfect view. I don't mind if the board cam gets a slightly restricted view. I suppose this means chopping into the nose a fair bit. Seems a shame on such a new plane but I don't want to ruin the aero.

Get the lens extension lead and then there is only the lens upfront with the camera inside the canopy.

QuoteI want to run it with a 3000mah 4 cell. Am I being too optimistic with this?

It will fly with that in, not as well as a 2200 but not bad.

QuoteHow much separation should I try to have between the video tx and Rx?

That all depends, with a 5.8 Vtx both inside the canopy is fine

QuoteShould I fit some end tips to try and increase low speed life and stop air slipping off the end of the wing? I don't really understand why this isn't standard? It is on many wings......?

It may stop high sped yaw wobble, but only when your gunning it

I bought a small balsa elevon and laminated it. Then glued some carbon control horns in with epoxy.

Quote from: Coyote on December 15, 2014, 01:28:12 PM

QuoteI want to fit my mobius to the very front so it gets a perfect view. I don't mind if the board cam gets a slightly restricted view. I suppose this means chopping into the nose a fair bit. Seems a shame on such a new plane but I don't want to ruin the aero.

Get the lens extension lead and then there is only the lens upfront with the camera inside the canopy.

That's a good idea cheers.

I can put it nearer the C of G then- maybe towards the video Tx side a bit to keep the noise away from the EzUHF.

Quote from: Coyote on December 15, 2014, 01:28:12 PM

QuoteI want to run it with a 3000mah 4 cell. Am I being too optimistic with this?

It will fly with that in, not as well as a 2200 but not bad

I think it's going to be too heavy with a 3000 4s. I have bought some 2200 4s. The sky fun seems to glide surprisingly well and I don't want to ruin it. I want a nice low stall speed while I learn to FPV something so fast too.

Will see how I get on at high speed and potentially add some wing tips to it.