Monday, June 16, 2014

Donkey Quad

Update:  Have one?  Building one?   Click Here: Donkey Quad Manual

A while ago I bought an inexpensive HobbyKing F330 frame, thinking I would use it with some SunnySky X2212-9 1400KV motors and 8" props I had.  Unfortunately, that turned out to be a very unstable combination.  It was fast as hell, and good at aerobatics, but I couldn't tune the shakes out of it.  I decided those motors were just too big for that small 330mm frame.

On a whim, I was looking at the cheapest 3S capable outrunners that HobbyKing sells when I ran across these ugly duckings here:

The Donkey ST2004-1550kv, "When pulling power matters and looks.. well.. just don't."

HobbyKing Donkey ST2004-1550kv
The mounts are nonstandard ugly aluminum tangs with holes in them.  The sticker oddly says "ST2204-1550kv" whereas the website part number os "ST2004-1550kv".  They have 3mm shafts, but don't include any collets or prop adapters.

But, they're dirt cheap, they work as advertised, and they're seemingly a lot more crash resistant than the similar-rated Park300 1400kv motors I used to use on a similar sized quad.

I had to use 4" zip-ties to attach them to the F330 frame.  I did it by threading the tie down through one hole, under the frame, up through the opposing tang, and then putting a cut off zip-tie "head" on the other end.  Repeat for the other set of tangs and you have a solid mount with no screws.  ;)
Mounted w/zip ties

Paired with some disused Afro 12A ESCs, a MultiWii MicroWii FC, OrangeRX R100 receiver, and some 7x4.5 props and I have a small, super light, fairly agile quad.  It's not the fastest one I own, but it's light and agile enough to do in-place flips or double-descending-rolls.

It turns out to be a joy to fly, and I've been spending more time with it than my more expensive quads.

Several people have asked me for a parts list, so here it is:
1F330 Frame
4Donkey ST2004-1550kv Brushless Motor
4Turnigy Plush 9g 10A ESC
1MultiWii MicroWii ATmega32U4 Flight Controller
1OrangeRX R100 DSM2 Satellite Receiver
1XT60 Male power connector
4Props: 7045, 7060, or 8038 (2 CW & 2 CCW)
43mm prop adapter
1ZIPPY Compact 2200mAh 3S 25C Lipo

A few build notes:

  • Use 4-inch zip-ties to attach the motors (described above)
  • You can use an XT60 to 3.5mm bullets power distribution cable instead, especially if you choose 10/12A ESCs that have 3.5mm bullets.  I built one this way, and one with directly soldered leads.
  • You'll have to bind the R100 to your transmitter with a separate receiver (or by flashing special Spektrum Satellite Bind Code to the FC first.)
  • This quad can actually carry a 2600mAh battery for 10+ minutes of flight time!
  • Add a lipo alarm to warn you when the battery is low.
I have two built right now.

One with 7060 phosphorescent props, UV LED strips on the arms, and a 4W spotlight:

The other with 8038 props, a GoPro Hero 2, Minim OSD board, and video transmitter on it:


  1. how did you mounted the motors to the frame?
    can you send me some pictures?

    1. I looped a 4" zip tie down one of the flanges and back up the opposite one, and then secured it on the second flange with the cut-off "head" of another zip-tie. Repeat on the other two flanges to make an "X" pattern.