Which electric motor for a 7" prop?
12-04-2005, 05:18 PM
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Which electric motor for a 7" prop?
Ive got a Hacker A20-20L outrunner which I usually run on a 10x5 prop, I have built an own design MiG 29 and wanted to use this motor to power it.
The max prop diameter I can use is 7" (to fit between fuz sides) so I went for a 7" diameter and 7.5" pitch prop - but the performance wasnt that great despite it weighing only 15oz.
It was suggested to me that outrunners are no good for smaller props as they dont rev very high (or rather they produce max torque at lower revs)
Should I buy an 'inrunner' for this model?
Which motor should I buy bearing in mind I want max speed out of a (max) 7" diameter prop and a 3 cell lipo (ie 12v)
Many thanks for any help
David Bevan
http://www.davidbevan.co.uk
The max prop diameter I can use is 7" (to fit between fuz sides) so I went for a 7" diameter and 7.5" pitch prop - but the performance wasnt that great despite it weighing only 15oz.
It was suggested to me that outrunners are no good for smaller props as they dont rev very high (or rather they produce max torque at lower revs)
Should I buy an 'inrunner' for this model?
Which motor should I buy bearing in mind I want max speed out of a (max) 7" diameter prop and a 3 cell lipo (ie 12v)
Many thanks for any help
David Bevan
http://www.davidbevan.co.uk
12-04-2005, 05:40 PM
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RE: Which electric motor for a 7" prop?
yes...inrunners are better for smaller props... I always thought innies were better.....
Hmmm.. I don't have much experience with the cans... but if it helps... I run a Mega 1615/4 on a Zagi and it screams... I ahve never tried a 7" prop, but with a 6 x 4 prop it runs very nicely...
5.5 x 4.5 is the best for me, but the 6 x 4 is nice too
I use a Kokam 2000mAh battery with this setup
Hmmm.. I don't have much experience with the cans... but if it helps... I run a Mega 1615/4 on a Zagi and it screams... I ahve never tried a 7" prop, but with a 6 x 4 prop it runs very nicely...
5.5 x 4.5 is the best for me, but the 6 x 4 is nice too
I use a Kokam 2000mAh battery with this setup
12-05-2005, 08:22 PM
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RE: Which electric motor for a 7" prop?
I run an AXI 2204-54 with a 7x4 or 7X5 APC Slow Fly on it. With a 350 MAH 2 cell 7.4 V batt it hauls my plane aroun. See thread on this section regarding this motor. My model does weight 6.7 oz. though. I think your plane may be to heavy. I ran the numbers on the AXI 2204-54 with an 11.1V batt and the thrust is right at 14 oz. with a 7X4 prop.
Hec
Hec
12-10-2005, 12:13 PM
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RE: Which electric motor for a 7" prop?
I have been advised that a Mega 16/15/5 with a 6x5.5 will be more than enough power. Ive ordered one, its arrived and I have got this connected to a 1600 3cell Lipo (11.5v)...
...but its totally pants! - i havent flight tested it yet, but on the bench im only getting 7oz (200g) of static thrust and is only drawing 7Amps.
What am I doing wrong?
David Bevan
http://www.davidbevan.co.uk
...but its totally pants! - i havent flight tested it yet, but on the bench im only getting 7oz (200g) of static thrust and is only drawing 7Amps.
What am I doing wrong?
David Bevan
http://www.davidbevan.co.uk
12-11-2005, 05:34 AM
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RE: Which electric motor for a 7" prop?
I just tested an Ultrafly B/06/15 Outrunner, and it performed well. I'm going to use it on an Ultrafly SU-27 pusher jet. With an APC 7X5E prop, it pulls 13 amps on a 3S pack, and produces 21 oz thrust. It only weighs 42 grams.
Mike H.
Cincy OH
Mike H.
Cincy OH
