Three new flights!

[sdg111]

Well, don't hold your breath, it's pretty poor and could make you sick, but, it is, my first recorded flight.

I actually had two longer and higher flights prior to this, when it was calmer, then I realised I hadn't put my SD card in the camera.

I played safe and pointed it down, at the side of the fuselage. It's no use. Next time I'll face it forward, taped to the battery box. I held the camera on with parcel tape and used some thread around the struts, connected to the camera, in case it came loose. As you can see, the picture is fine, it's just the angle (and wind) which make it pretty useless. She was actually getting away from me downwind so I got her down as quickly as i could.

The camera itself is an absolute steal, and very easy to save and upload. I'll try and post a better video in the next couple of days, hopefully a few fields down so I can see my village.

www.youtube.com/watch?v=NnUjyJNgaU4

www.youtube.com/watch?v=c2ZGxvxFKYg&feature=channel&list=UL

[sdg111]

Two further videos. Camera now under right wing. I think the motor sounds really rough on these flights. Something is definitely amiss because I almost lost control at the end of the first flight and did lose control on the second flight, but managed to land her upright almost three fields away! I was very lucky, because I could barely see her, but cut the motor and tried to flare her so she came in nice and soft.

When I got back and heard the footage, I stripped off the prop shaft, gearbox etc and screwed it all back together checking everything. I don't know what you guys think the problem could be?

Could it be a range thing in the second flight? I guess she landed several hundred yards away. Batteries should have been okay and total flight time was only about six or seven minutes.

www.youtube.com/watch?v=x11CIbiimlg

www.youtube.com/watch?v=c2ZGxvxFKYg&feature=channel&list=UL

[flydiver]

Motor does sound terrible. Something is vibrating.
Suspicions:
Prop is cracked, bent, or out of balance.
Prop shaft is bent.
Bearing is shot, or gearbox is put together wrong-too much slop.
Firewall is cracked.
Screws on GB are loose to firewall.

No idea why it might cut out for sure but a motor sounding like that is under a much higher load, therefore pulling a lot more amps and could trigger an ESC shutdown or suck the battery down faster than you think.
Check battery voltage afterward. If it's below 11v you likely sucked it dry.

If you've been flying to LVC > that's hard on the battery. The LVC setting on the stock Cub is poor.

If you keep your battery fully charged and in a warm (or worse hot) area > that's very hard on it.

The stock battery isn't so good anyway.

[sdg111]

Thanks Fly, yeah it doesn't sound good does it, although in the flight I recorded the day before it sounds fine and it hasn't been crashed between then and now, so I think something's comes loose.

When I got back, as I said, I stripped it down and checked
1) - Prop - seemed fine but changed it to a new one anyway
2) Replaced prop shaft as had a spare in drawer, although old one seemed fine
3) Bearing should be fine - new gearbox (what is too much slop?)
4) Examined firewall again, no sign of any cracks
5) Checked screws all around, I had a heck of a job getting the screw in front of the prop off, maybe I overtightened it, but I find if I don't tighten it good the prop forces it loose.

LVC - what is that?

Battery is kept charged, should I store them empty and charge just before I fly?

I flew it again today and it sounds better since I stripped and re-built so hopefully sorted, but we'll see.

Thanks Fly, I was hoping you'd read this.....

[sdg111]

Okay, just checked.

LVC - low voltage cut-off, could be the case 'cos I could still control the landing just had no power to gain height.

SLOP - is it that something's loose? Prop or gearbox?

Fly, when you say gearbox is put together wrongly, I'm not sure what you mean. Is it not just a case on connecting the two cogs?

[flydiver]

Lipo basics - read this:
sites.google.com/site/tjinguytech/charging-how-tos/lipo-terminology
He has a lot of other really good info. Bookmark and browse.

Slop - something looser than it should be. There are certain bushings and stuff on the prop shaft. There is an order to the parts. I no longer have one so can't provide details. It needs a bit of fore and aft movement but not too much, and no binding. People do put them together wrong.

Prop balancing - get a prop balancer and use it. Assume ALL props are screwed up until proven otherwise. Cheap ones more so. I've had brand new PZ props be a piece of bent garbage.

Prop balancing video tutorial: www.youtube.com/watch?v=N02NHYrpA0g
This guy goes a bit overboard but the majority of people do nothing at all and wonder what the problem is. Some of the cheap props coming out of China are real junk.

Personally I add nail polish to the back of the light side. Easy, quick and works well. Black and clear cover most bases fine.

[sdg111]

Thanks Fly. Going to start looking at prop balancers now.........

[flydiver]

2 basic types:
Cheap - finger tip
More expensive & much better - magnetic type on a stand.

I actually use the fingertip kind and put 2 rare earth magnets in my vise and "make" a magnetic one.

[sdg111]

Thanks Fly. Temporarily used a cocktail stick and messed about with a prop, sanding and glueing etc. What a wonderful world this RC flying is!!

Lots of good stuff on YouTube about this.

My motor sounds fine now but would like to upload a video to get your opinion. Sadly, we're in for two days, at least, of very heavy rain in the north east of Scotland. Apparently a months rain in two days! thankfully we're on a slope but not at the bottom of it...

When the weather's good again I'll try and record another flight or two .

[toff]

Despite the fact that the motor sounds awful......well done! 3 flights with adverse conditions, and no crash! And, although you're weather watching and wanting to get out, don't feel too bad, I've had only 2 days in the last 2 months to fly ...mostly due to work (curse of the flying classes!), theres only been a few days when it hasn't either rained of been too windy.
Thanks for the vids, and keep it up! you're doing really well!
chris.

[sdg111]

Thanks Chris, I really appreciate your encouraging comments. Yeah, work's a chore but pays for the spares I suppose!

Weather has been awful the last two days and now I'm not off for a while so it could be a couple of weeks before I can record some more flights, but fear not, more will be posted as I really enjoy watching them, I hope some other do too.

Thanks again,
Steve