thanks for all the input educating me on the motor. i saw a kit plane ( micro telemaster ) in hobby lobby. this one need to get my own electronics. well, this seems good learning experience from what i've read from your post.
Following is the brushless requirement for this little plane ( 10 oz in weight),
prop size 7*4, i am planning to fly with 2 lipo ( 7.4volts) name of motor reconmended by manufacturer :AXI Gold 2203/52 . 12 Amp Brushless Controller -12 amps continuous, for use with 6-10 NiCad or NiMH, 2-3 Lithium cells. BEC can run 4 servos with up to 3 Lithium cells, or 3 servos if 10 NiCad/NiMH are used.
No. of cells 2 Li-Poly
Max. efficiency 74%
Max. efficiency current 2 - 5.5A (>69%)
Current capacity 7A / 20s
No load current 0.4A
Internal Resistance 390mĪ©
Dimensions (Diameter x Length) 27.5 x 21mm
Shaft diameter Carbon 3mm
Weight with cables 18.5g
now the math part for my lesson
10oz plane will be 0.629 pound. if i want to park fly ( 75Watt), then the motor requirement is 75Watt*.0629pound and it will be 4.7175 watt. So i round to 5 watts motor. Am i correct so far?
then i go to maxxprod and found few motors there. I am picking one HC2808-0860kv.
HC2808 - These 100 watt motors are for small models weighing 9-12 oz for 3-D flight, up to 16 oz for aerobatic flight and up to 20 oz for leisure flight
this is spec of that motor
Part No. Dia mm Length mm Weight g Shaft Dia Prop Size* ESC Rating Kv Rm Io
Learn more 28 25 52 4mm 9x5-12x6 10 860 .255 .36
efficient operation cuttent=2-7A, 11A max 15 seconds
These are my questions. diameter, and length is not a big issue( i have good background on fixing my nitro buggy every few weekends).