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Old Aug 15, 2012, 04:59 PM
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l've found that descending via loops/rolls/etc is a much more controlled and enjoyable method rather than just decreasing the throttle. I would actually be terrified to descend by just lowering the throttle from very high up.
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Old Aug 15, 2012, 05:07 PM
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Has anyone succesfully mixed the mQX and v929 yet? Either by fitting the mQX board on the v929 frame or fitting the v929 booms in the mQX frame?
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Old Aug 15, 2012, 05:25 PM
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Originally Posted by krede85 View Post
Has anyone succesfully mixed the mQX and v929 yet? Either by fitting the mQX board on the v929 frame or fitting the v929 booms in the mQX board?
mQX board does fit on the v929 frame 1:1 but the plugs a different.
v929 uses Micro JST 1.25 plugs :
http://www.ebay.com/itm/180933354171...#ht_1967wt_954
http://www.hobbyking.com/hobbyking/s...5pcs_bag_.html

It shouldn't be hard If you can solder

I haven't checked yet how the v929 booms fit to the mQX Frame. But I don't see any Problems. Maybe you need some hot glue to fix them.
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Old Aug 16, 2012, 04:05 AM
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Originally Posted by Brandigan View Post
True, but not quite all, it depends on the size of the props. My U816 (UFO canopied Walkera Ladybird clone) has such tiny props and they spin so fast, (it feels like it could almost fly in a vacuum ) and I can just shut the throttle right back and it will plummet out of the sky and I max the throttle 6ft off the ground for a cushioned landing.
Yeah, but the prop wash is still there and having an affect. Try a slow descent through your own prop wash you'll get similar results to the mQX.
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Old Aug 16, 2012, 04:17 AM
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Originally Posted by Brandigan View Post
Sounds perfectly normal behaviour from a new, old or any MQX, as well as the v929 Beetle clone.

You're possibly doing things more quickly than you used to as your flying confidence has grown.

As lowering the throttle too quickly means the props are not giving as much lift, and with no wings to keep it up, it flies much like a brick will.

Try a different technique, something like this, or like this in smaller stages if you have a small area to fly in:
http://www.youtube.com/watch?v=H83-VkKRp1g
Thanks for that.

This is actually the method i've been using to get back down to earth.

Perhaps it's completely just my confidence levels rising, i'd been mostly just hovering around gently in the house when the weather has been bad and staying fairly low with a bit of forward flight. I'm now getting the hang of things and the speed and height i'm flying at are both increasing.

After a bit more play last night I think I may have stumbled upon an extra factor though, I think the cheaper batteries I have struggle when suddenly increasing throttle to a fairly high level and this is perhaps giving unbalance in the motors that the brain of the MQx is compensating for. Using decent batteries certainly reduces the effect.

note to self * don't buy any more cheap batteries.
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Old Aug 16, 2012, 04:56 AM
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Originally Posted by mystman View Post
mQX board does fit on the v929 frame 1:1 but the plugs a different.
v929 uses Micro JST 1.25 plugs :
http://www.ebay.com/itm/180933354171...#ht_1967wt_954
http://www.hobbyking.com/hobbyking/s...5pcs_bag_.html

It shouldn't be hard If you can solder

I haven't checked yet how the v929 booms fit to the mQX Frame. But I don't see any Problems. Maybe you need some hot glue to fix them.
Thanks I might give it a try sometime soon then!
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Old Aug 16, 2012, 06:01 AM
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Originally Posted by fred_dot_u View Post
I would also consider unbalanced performance from the motors, relative to each other. What appears to me from the description is similar to a full-throttle take off where one or more motors are providing unbalanced power, so the ascent is not even. Reducing power for a descent with one motor dropping power more than another could result in this tendency.
There are a couple other (related) possibilities....

You could have a damaged or bent prop that as a result does not produce the same thrust as the others. If this requires its motor to reach 100% throttle at any point in the descent, you may see stability issues.

You could have a boom that is either pulled out or pushed in. My mQX had an internally damaged frame and two of the booms could be pushed in too far... or more often, one would push in and that would push the opposite boom out. It flies much better after I replaced the frame and all the booms are symmetrical again.

Try a brief full throttle climb from a power off start on the ground. It should go straight up. If it doesn't, you have a weak motor, bent prop or pushed in/out boom.

Paul
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Old Aug 16, 2012, 07:14 AM
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Originally Posted by Gerry__ View Post
Yeah, but the prop wash is still there and having an affect. Try a slow descent through your own prop wash you'll get similar results to the mQX.
No, I don't get that effect with my U816, although I do with my MQX and my v929 Beetle (same thing, basically). I already tried slow U816 decents because of my expectations and was unaffected by prop wash because there isn't any to speak of with such tiny props, so I did it faster and faster until eventually I found I could just about close the throttle, drop like a stone and catch it with a full throttle burst before it hit the ground. Not advisable as the battery gets nearer its limit as there is a bit less power in the last minute of flight for stuff like that. But then I just catch it with my hand.

And to whoever asked: Yes, just about all the spares except the board, and frame section are pretty much interchangeable between the MQX and the v929, although the plugs on the board/motors are different. Booms: same, props: same (colours different). Motor mounts: different design, same fit, Motors probably same, but cable colours swapped: Red/Blue= Black/White and vice versa

On the v929 forums we're all waiting for Rev03 which has flashing LEDs on the legs, which one person got very early (presumably by mistake) but without the new Transmitter with the extra channel button to toggle them on/off - which the beta tester has reported as coming soon - (they're on permanently, no biggie)
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Old Aug 16, 2012, 07:45 AM
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I just received mine the other day, put on about 15 flights already and love it!

I attached my key camera #16 on it and it lifts the added weight fine but was acting very squirrelly in the air. I attached it to the battery cage with velcro and I tried to center it as best as I can but maybe I wasn't in the right exact center? Any ideas or tips?
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Old Aug 16, 2012, 08:01 AM
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Originally Posted by Brandigan View Post
No, I don't get that effect with my U816, although I do with my MQX and my v929 Beetle (same thing, basically). I already tried slow U816 decents because of my expectations and was unaffected by prop wash because there isn't any to speak of with such tiny props,
There is definitely prop wash, as all props create it. There will be a proportional affect on the U816.
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Old Aug 16, 2012, 08:17 AM
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Originally Posted by Gerry__ View Post
There is definitely prop wash, as all props create it. There will be a proportional affect on the U816.
Ok, well as you clearly don't believe me telling you it is close to negligible on mine, why don't you buy yourself a U816 and tell us how proportional it is?
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Old Aug 16, 2012, 08:23 AM
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Originally Posted by Brandigan View Post
Ok, well as you clearly don't believe me telling you it is close to negligible on mine, why don't you buy yourself a U816 and tell us how proportional it is?
Just looking for a UK source.

Anyway, no prop wash? I don't think so, not if the laws of physics have anything to do with it.
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Old Aug 16, 2012, 09:08 AM
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Originally Posted by Gerry__ View Post
Just looking for a UK source.

Anyway, no prop wash? I don't think so, not if the laws of physics have anything to do with it.
The laws of physics as you understand them? Well, have a look at this short video and prepare to be amazed.

(Not really, it's just as I described before)

http://www.youtube.com/watch?v=zcfAarsmT8M
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Old Aug 16, 2012, 09:13 AM
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Originally Posted by Brandigan View Post
The laws of physics as you understand them? Well, have a look at this short video and prepare to be amazed.

(Not really, it's just as I described before)

http://www.youtube.com/watch?v=zcfAarsmT8M
Ok, but can you video a slower descent? Dropping like a stone with the throttle cut isn't quite the same thing.
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Old Aug 16, 2012, 09:35 AM
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Ok, but can you video a slower descent? Dropping like a stone with the throttle cut isn't quite the same thing.
Oh, it'll drop faster than that with the throttle cut. That was relatively controlled, fast, descent. If you go back far enough and read what the problem was: the whole point is that anyone can descend slowly and not be affected by propwash, but it takes ages to get down, after you've applied buckets of throttle to get yourself 50ft up. It's descending quickly that is the problem.

The initial instinct is to close the throttle too much, which a) reduces lift to the point where the quad is flying exactly like a brick doesn't, and b) is now falling through mucky air which - because of the reduced lift/control of the slower moving props - has a greater effect in throwing it about.

With bigger props, you have to be moving forward to get out of the mucky air and either circle down, or apply lots of pitch or roll to dive towards the ground (props still at high speed, so actually doing some work) and then aim to miss it.

The video illustrates that smaller blades are not affected by fast speed of descent, which is why it didn't wobble and I applied throttle in the middle of the last descent and went back up again. Slow descent is even less affected, just like with every other quad.

The main problems I had were trying to keep the quad in frame and also it's a lot happier in larger areas. Outside it goes like a little rocket, much faster than either my MQX or v929.

Apology accepted BTW.
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Last edited by Brandigan; Aug 16, 2012 at 10:00 AM.
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