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Old Mar 30, 2007, 06:27 PM
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Chattanooga, Tennessee, United States
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Since Tom has made some comparisons between Scorpion and Hacker and Axi, perhaps it is time I contributed some of my test data.

Here are some figures for the 2208/34, 2212/26 and 2215/22 which Lucien and Georges sent for me to play with. You'll see that I often tried to use 10.5v and 14.0v to match up with Lucien's posted data.

Tom, I haven't made exhaustive analysis but, for some reason [pusher stand?], though Lucien seems to get slightly higher rpm at similar amp draws, his thrust numbers are a fraction lower than I would get at that same rpm. So the Scorpions may be a bit closer to your Hackers and Axis than you thought.

I am still concerned about heating, especially when the motors are loaded with large props. Put smaller props on 'em and, even at higher voltages and higher total watts, they do well.

Some earlier prototypes got rather hotter, rather faster - but all the data presented here are for factory packaged motors, presumably plucked straight from Lucien's shelves - what you see is what you get.

It is not easy to find exact matches (weight and Kv) for these Scorpions, but I've made some comparison with somewhat similar motors.

I found that the Scorpion ESC's set on default, seemed to limit current draw quite a bit. Apparently 15 degrees advance gets you a little more power, but I have not tried that yet. I found that my trusty Phoenix 25, set on default, did a good job, so all these tests were done with that ESC.

One somewhat mystifying result was that all of the motors I used for comparison, though lower in Kv than the Scorpion I matched them with, drew similar or somewhat higher currents (with a proportionate increase in power output). The 1100Kv 2208/34 Axi was very close to the 1206Kv Scorpion 2208/34, but really should, I would have thought, have drawn significantly less. The Komodo 2208-8 (1150Kv) also drew a bit more than the Scorpion 2208/34 and generated a little more rpm and thrust. The Torque 22T/930 drew a lot more than the 994Kv Scorpion 2212/26 - in fact I dared not try the Torque on 4s voltage (as I did the Scorpion) because it would have been way over its limit. And the Axi 2212/26 (920Kv) should have drawn less than the 987Kv Scorpion 2215/22 - but in fact it drew almost exactly the same current at the same voltages.

In general, these beautifully packaged, loaded with all the accessories, modestly-priced Scorpions perform well - the watts/rpm graphs I generated indicate how similar they are to others brands of motor of roughly the same Kv and weight.

The numbers are here for you all to peruse, compare, and comment upon.

Cheers, Phil
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Last edited by Dr Kiwi; Mar 30, 2007 at 06:42 PM.
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