Art Tech (from Hobbyking) 64mm EDF Mig-15

[lobstermash]

I got one as a Christmas present. Was quite a quick build, good quality paint job, all the electrics worked fine. Even took it for a few taxi laps around my back deck. Then, about an hour later I plugged it in again. There was a noise like a thump and the battery wires went hot. I promptly unplugged and a smell like burnt tobacco filled the air. I plugged the battery in again, and the ESC powered up as normal, but the motor didn't work. I had a laugh when I opened the plane up, pulled out the motor and it had a QC29 sticker on it. I'll look out for Mr(s) 29 in future I think...

Long story short, I'm going to have a try with HK to see if anything can be done. I'm not going to hold my breath, but you never know...

Anyhow, I'm thinking about what to do in the absence of any type of customer support...

I've got 2x 1600mAh 20C 3s, and they balance the Mig-15 really well. I may in the future upgrade to 4s however.

So I'm tossing up between getting one of these: 64mm 3s-4s EDF with motor

and one of these: 2610 4500kv 3s motor

The former isn't going to be quite as powerful on 3s as the latter, but will plug straight in without having to stuff around with tight shafts etc. And it can be given more go with 4s. It's only $20 + $5.99 postage.

The latter is supposedly good for 600g thrust on 3s at 27A, but can't be upgraded to 4s. I'll have to change the shaft over to fit the stock EDF, and they're notoriously tight. They're priced at $10.44 + $3.99 post.

 

[earthsciteach]

Argh! That stinks. Are you sure the motor is dead and a solder didn't come loose? I wrote a motor off for quite a while, then as I was straightening things up, I noticed that it pulled a load when two leads touched. Sure enough-solder came loose when it heated up! Its still flying.

 

[Brian fred carr]

Bad news lobster...what a way to taint the yuletide with a dodgy motor....... I am also distressed, an order I thought would be
here Christmas eve has not even left hong kong even though I ordered it from the German warehouse....my kids have loads of new toys and I have none....boo hoo

 

[lobstermash]

Haha, yeah, I've got a Christmas present still in Hong Kong. I just missed getting a 9x (for my boss) on the last shipment, which held down my Christmas present (FPV tx & rx).

At Earthsciteach, you can't open up the motor at all, as it's all sealed tight under a big heatsink. But the shaft is very stiff to turn, where as it was nice and easy before. Thanks for the suggestion though. By the smell and the stiff shaft I'm guessing bearing(s) are the cause.

 

[earthsciteach]

Stiff shaft.. hehh hehh hehhh...

Yeah, I'm always losing my bearings, too. I have at least three motors that I could put back into operation if I had replacement bearings. My LHS isn't much help for some reason.

 

[lobstermash]

Haha, for what they'd charge you to fix them you could buy several motors from you know where... My LHS charges a ridiculous $40 for a brushed motor. I went in one day to have a look at a few things, and went past their cabinet with the motors. I couldn't hold back my mirth. And one of my mates got a few Deans plugs from there. They charged him $5 for a pair. However their planes aren't too badly placed. The Skysurfer rtf (Bixler) is $219, most of their Parkzone micros are around $120 (rtf). A DX6i sets you back about $170. But enough LHS bashing...

Any suggestions on the OP?

 

[lobstermash]

I've lodged an email with HK support... I won't hold my breath on this. I just hope they get back to me before my order is printed...

 

[lobstermash]

I've decided I can't wait forever, so with warranty claim in progress I've bought one of these: http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=10924

 

[colorex]

Nice

 

[lobstermash]

I've been told I have to send the faulty items back. It'd cost me more in postage than just wearing the loss and buying new items... I managed to get the motor open, and it's got a nice black streak where it has shorted. I also tried the ESC on a different motor and found that it's stuffed too! Wonderful! So I've got a motor on the way, but no ESC... they've printed my only outstanding order now too If I knew I had to buy a new combo I'd have got something with serious go...

 

[lobstermash]

OK, I've finally got the motor for my Mig, but still waiting on a couple of ESCs. I fired it up to half throttle with a 20A job and there seems to be more than enough power to get this thing going pretty well.

 

[lobstermash]

It seems like forever since I got this plane, but I haven't removed it from my model list in my 9x yet. I got a couple of 40A ESCs in late January, but didn't realise they were opto. I soon ordered a couple of UBECs from ebay, but they've taken over a month to arrive. They're finally here though, and I've been working on the Mig tonight. I've managed to make the chunkier gear fit, and balance out the heavier motor with a 2200 instead of the recommended 1600.

Putting it on the scales, it comes out an obese 750g... I'm not optimistic about it taking off, let alone flying. Motor is supposed to put out 620g thrust according to HK's notoriously wonky figures.

 

[lobstermash]

Well, it has officially been maidened! Opened and put together on Christmas day, maidened 17 March. I took it down to the local oval and put it down the cricket pitch. It tracked nice and straight, but didn't seem to generate much lift by the end of the runway, so I was about to abort when it started to take off... Damn. Mild cartwheel over, but everything was fine. Take 2, I didn't go quite as straight, but had most of the runway, and it didn't generate enough lift to take off. Take three, I kept it on the pitch (middle stump) and the wheels gently kissed the grass as it lifted off. Climbed without too much trouble, tracking pretty true. The elevator control is adequate, but not ballistic, and the roll rate is scale (just right). On a diving run, it can generate a decent amount of pace - my guess around 100-120kph (60-70mph). It's just the right size for a cricket oval and flies better within it than my 50mm EDF A6. I took it up high and stalled it too, and it keeps tracking OK, though certainly not a glider! I flew it for about 5 minutes before I started to think about bringing it in for a landing, on which I hit the deck a little harder than I'd hoped, bounced and nosed over on the grass. The nose wheel was bent back a little, but nothing too drastic.

All up I'm very happy with the flight performance and looks in the air. Perhaps the EPS is a nice homage to Russian engineering - cheap, simple and light. It's a shame that I've had to tweak the powertrain thanks to poor stock electrics, but the additional gear has been cheap and provides a lot more security in the air. I've spent probably about 4-5 hours on this plane, modifying the canopy, soldering up the new ESC, fiddling with the build etc.

I'd recommend one of these, but throw away the original inrunner and get a 2815 outrunner, and replace the awful stock ESC with something like a Plush 40A.

 

[lobstermash]

Hmm... What I forgot to mention above is how much altitude this thing loses in the turns... That wouldn't be a problem as long as you remember it, but I made a big boo boo today and struggled to recover from a stall. Boo boo turned into a boom boom. I'm not convinced I'll be able to fix this too easily. Anyone into jigsaw puzzles that require reshaping of warped EPS?

 

[lobstermash]

And she lives! I only had to make one custom piece.

 

[colorex]

Looks like a plane I don't want to own...

 

[glydr]

Wow. That was quick.

Does the nose sort of ... bend ... to the right?

 

[lobstermash]

Haha, no the nose is OK. All pretty straight!

For an EDF, it's pretty gentle Andre. It's fast in the dives but a baby in their air until you start getting a bit silly... Quite scale actually.

 

[colorex]

until you start getting a bit silly...

*sigh* - I get it. A friend just broke his double reinforced Bixler spar because of the same reason.

 

[Mike oxbig]

Good job on the repairs! If I hadn't seen the before pic I would have thought it was just a little hanger rash.