Guys,
I went out to drain (what I thought would be) the little bit left in
the DDs' battery and it ran for 5+ minutes! So, it didn't have a low
battery on the first flight, just one that couldn't deliver enough
amps. On that flight, the takeoff was great with a good climb out,
but within a minute the DD didn't have enough power to stay airborne.
On the advice of "Radical RC" I had bought a 7 cell 300mah NiMh
battery. This is supposed to be the perfect match for the IPS motor
that comes with the GWS Sticks. Also, they advise against going with
an 8-cell battery for "draggy" (Desert Duster) designs.
There are some differences between the drive that comes with the GWS
sticks and the one I bought. The sticks come with the IPS Dx2 AXCS, I
bought the ------2XCS. See below.
AXC on 7.2 volts - 10 x 4.7 prop, thrust = 129g @ 1.67A
2XC on 7.2 volts - 7 x 6 prop, thrust = 115g @ 2.01A
2XC on 7.2 volts - 8 x 4.3 prop, thrust = 123g @ 1.93A
I flew it on the 7060 prop. I do have an 8043 prop that I can try.
On a bench test (7060) the amps quickly dropped below 2A and most of
the run was closer to 1.6A. I know that changing the prop will change
the amps, but if the 8043 still doesn't have enough power, what should
I try next?
As this is a different drive, should I try an extra cell? At the
price of these motors, I don't mind burning one up, but I would like
to find a reliable drive for the DD. How about going to the AXC? It
looks like it produces more power on fewer amps, but I don't think the
DD would ROG with that larger prop. Or should I try Nicads? The same
physical size Nicad would be in the 110 to 150 mah range. I have read
that Nicads dump their amps at a higher rate then NiMhs. Radical RC
claimed that these were high rate NiMh, and were similar to a Nicad in
that respect.
I know this is a lot to ask, but any thoughts would be helpful.
Thanks,