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J-S-Q
09-18-2008, 04:35 AM
Well after waiting a couple of weeks to get one of my cyclic servos from a website that claimed to have them in stock for next day delivery (thanks!), I finally got my SJM 430 in the air. Setup is as follows

Cyclic: HD-2213MG (cheap and arguably a bit small for this heli. 2.7kg/1.6sec)
Tail: S9257/GY-401
2 x 3s 2200 30C Zippy Lipos
Stock motor/ESC, with 14T pinion.
Stock 430 blades.

http://i171.photobucket.com/albums/u316/jquinn_2007/SJM430Small.jpg

(Picture shows the older V1 canopy by the way -the new one looks great too, it just depends what mood you're in!)

The very first flight was nearly a disaster -the heli was all over the place and seamed to have a mind of it's own. Landed after a minute or two and found that the elevator ball link on the swash had backed out and very nearly came off altogether, causing massive slop in the head. I think I must have forgotten to loctite that one after refitting the swash during setup. Very lucky not to have crashed.

Having fixed this problem, I got two more flights in -just taking it easy, mainly hovering. Everything was very smooth -no sign of vibrations at all which is good as I've read of people having problems with the heli shaking on spool up or in flight. Nice and stable in flight and very quiet, but definitely feels different to my Trex 450 and 600N. Hard to describe exactly how but it's definitely different. I'd say it felt 'softer' on the cyclic (My Trexes have much higher spec servos compared to these cheapo ones by the way). The first flight, it definitely felt a bit strange but the second one I grew a bit more comfortable with it so I think possibly it just needs a little getting used to. I had it setup with 10 degrees of collective, and 5 cyclic with 25% expo so probably a little tame so I might play around with this. There was also a little bit of intermittent tail wag (quite fast left/right movement of about 0.5 cm). I think I just need to play around with the gyro gain a bit so shouldn't be a problem.

I set my timer for a very conservative 3 minutes and have put back about 770ma into each pack. On that basis, it should be good for nearly 7 minutes at 80% discharge on these packs but I'd rather play it safer than that and maybe go for 5.30 or 6.

I did notice that the batteries, ESC and particularly the motor were pretty warm after landing -definitely more so than my 450. Not sure whether this is normal or not with an electric heli of this size.

Anyway... I'm very happy so far!

J-S-Q
09-21-2008, 05:34 AM
Well I got rid of the wag but everything would be fine for 30 seconds or so and then the tail would just kick out really fast. This got progressively worse with further test flying and at one point it even did a full 360 in about half a second (while my friend was test flying it a couple of feet off the ground -amazingly he landed it safely!). After a whole afternoon of going over the mechanical setup and making various adjustments, I finally realised I had a faulty 401. Switched it for another one from my TRex 600N and everything is now solid as a rock on the tail. The heli is now flying great! Just been doing circuits with it so far but it's very smooth indeed and has quite a 'big' feel to it. I can definitely recommend the 430 if you want to try something different from the mainstream helis out there.

ZzEther
09-21-2008, 07:09 AM
Well I got rid of the wag but everything would be fine for 30 seconds or so and then the tail would just kick out really fast... I finally realised I had a faulty 401.

Congrats on the build! Let me ask you about your gyro. I thought I saw a forum somewhere where a guy had his gyro wires folded up and crammed under that carbon plate the gyro mounts to and he had glitchy problems like you describe. Then he pulled those wires out from between that plate and the boom and the glitchy went away. He did a video where he showed it right there on the bench. Just curious if you had your wires crammed in there....

J-S-Q
09-21-2008, 07:18 AM
Yes I read that same post. If I remember rigthly, the problem that the poster was having was excessive vibration, and not glitching (could be thinking of a different post though -it was on RC Groups by a guy called Nexus?).

My wires weren't crammed like that. The gyro was definitely faulty. Even when it was not mounted on the heli, as soon as it was powered up, the servo would start moving with no stick input. I posted about it here:

http://www.helifreak.com/showthread.php?t=94403

As soon as I switched the gyro, exact same radio settings/tail servo etc, the problem went away.