I got a Motorworks car from Wal-Mart a while ago, and considered doing a conversion using the Rx and motor. However, I was not set up for lipoly charging at the time, so the project would have been fairly expensive. Fast forward a year. Now I have more equipment, etc. and gave this a try. Thanks to mcross, who helpfully volunteered to get a Kokam 145mAh cell and some other small components for me, I have had some success. I'm still working on downthrust angles and trimming, etc. as it tends to climb rather steeply when I hit the throttle. Also, I think the rudder needs to be enlarged - turning response is slight. Here are some pictures. Complete weight is 14 grams. The battery is not shown in the picture.

Some specs:
Motor: stock Motorworks
Rx mods: longer (18") antenna, LED removed
Tx mods: none
battery: 145mAh Kokam
Prop: Ikara Butterfly
AUW: 14g
wingspan: 16"
chord: 3.8"

The airframe is my own design, loosely based on the Minnow or any of several free flight airplanes. The fuselage stick is two pieces of 1/16 x 1/8 balsa laminated together. The original wing was 18" wingspan polyhedral, covered with tissue. This was too heavy, so I replaced it with a 16" wingspan design using only 5 ribs and grocery store plastic for covering.

stjobs
Looks good, glad I could help.
Your rudder looks plenty big, the problem maybe somewhere else. Can you post a pic of the coil and magnets?
Mike

Here's a picture of the coil. It's somewhat hard to see. The control movement is about 25 degrees in either direction.

Looks like it should work if it's solid. Is the rudder flexing from the wind? Looks like tape is holding the foam to the stick, is it glued also?
When a turn button is pressed is the magnet centered on the coil?
Another thing that may help (if everything I mentioned is ok) is to make it into a parasol, the higher wing will help it turn better.
Mike

The wing is actually mounted on two struts - it's difficult to see from the picture, but it is about 1/2" above the fuse stick. I can easily change this to 1". That would probably improve the turning characteristics.

Yeah, the rudder movement is fine. I taped it on so I could easily change to a different rudder, but there's no floppiness when the actuator is energized. I tried hitting the turn button and blowing on the rudder - it doesn't move.

It may have something to do with the "lifting stab" you were mentioning earlier. I did mess with the angle of incidence, but I was never able to get a good glide at 1/3 chord CG. Currently it's at about 1/2.