Originally Posted by FishHawk
I understand about weighing everything. But if my motor or battery is lighter or heaver than the suggested weight is where I'm confused.
If the designer used a lipo battery and I'm using a Nicad battery that weighs more how do I determine what the designer says if the correct weight for the various components? FishHawk
What is the wingspan and wing area of your model, or the make and model mfg?
The original Nicad batteries were kind of OK for electric power, years ago. The newer Nickel Hydride batteries got rid of the hazardous cadmium, but in the process, those Nih cells can't put out the same current at the same voltage as the original Nicads. At least, that's my opinion, having tried both in the years gone by.
Now, we've got the LiPo batteries, available in a very wide variety of sizes, from real tiny for models less than one ounce, to big enough to fly a 20 plus pound giant scale electric model. LiPo batteries do have a fire risk, but using a quality BALANCING
type battery charger does a lot to reduce that risk.
If you're worried about fire hazards and LiPos, there is also those A123 cells. They can not ignite (Yeah, I tried it
) but they weigh about 35% more, have lower voltage, and are about 30 % larger in physical size, compared to an equivalent LiPo battery pack.
That kind of rules them out for models of the size you're considering. I'm using those A123 battery packs in models ranging from about 48 inch wing span, up to two giant scale models with 82 inch wingspan, and 17 pounds. They are running between 2500 and 3000 watts. Nice thing about A123's, with a proper high powered charger, they can be recharged in 15 minutes or less, so you don't need a pile of batteries to fly for an afternoon. At our club fun fly today, I put on 8 flights on two different giant scale models during a period of three hours. With a bit of gabbing in between.
There are about 100 A123 cells in my various models, and so far, they seem to outlast the models they are installed in. After several hundred flights, they turn the same exact motor, same prop at the same exact RPM. And, do it with better than 90% of their original ampere hour capacity.