Okay here is the complete write up with images linked in...
I thought I would let you all on some information in regards to converting a 0.40 sized trainer to electric. Sure the smell of Methanol is good, but wouldn't you all like to go home not smelling like it, not cleaning it off the plane etc...
I had an O.S. 46AX engine in my Boomerang Trainer and thought, why not convert the plane to electric. It's cleaner, I can just plug a battery in and go. Don't have to waste time playing with the tuning etc... I wanted flight times similar to that of the fuel so I had to do a bit of research. Flight times with the below config will give me between 10 and 15 minutes depending on how I fly.
Motor: Turnigy SK 42-50 650Kv
ESC: Turnigy Plush 60A
Battery: 4S1P 3000mAh 20C Lipo
Performance: 8800RPM @ about 35A.
More than enough for the Boomerang.
CLICK ON IMAGES FOR A LARGER VIEW!
SO I set out and modified the top of the Boomerang to allow a hatch to be installed.
Added some airscoops to the sides and in the hatch also.
Made a new hatch out of some spare balsa wood and plywood. and Fibreglass the inside of this for strength.
Painted the hatch up and applied the original window decal to it..
Made a new firewall. this ended up being about 40mm further forward.
Added an exit hole for the air to pass through the plane, the mesh is just flywire from a window. Epoxied on.
and added the electrics to it.