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MountainFlyer
12-14-2005, 10:36 AM
ive been playing around with Motocalc. and these are what ive come up with for the power system im planning on putting in my GWS Zero.
the zero's AUW is around 13.5 oz. i may have to add some more weight to balance it out.. but this is its current specs. the motor is a brushed GWS EPS-350C with a C gearbox now if Motocalc is right 11.5 amps is not excessive for this motor and i wouldn't be flying it at full throttle all the time anyway. The motocalc version im using is the latest 7.09

Gear Ratio = 5.33
Diam (in) = 9.0
Pitch (in) = 4.7
Weight (oz) = 13.5
Batt Amps = 11.5
Motor Amps = 11.5
Motor Volts = 10.3
Input (W) = 118.3
InPLd (W/lb) = 140.4
Loss (W) = 37.3
MGbOut (W) = 81.0
OutPLd (W/lb) = 96.1
MotGb Ef(%) = 68.5
Shaft Ef(%) = 63.6
Motor RPM = 44372
Prop RPM = 8325
Thrust (oz) = 20.2
PSpd (mph) = 37.1
RofC (fpm) = 1736
Time (m:s) = 4:43


Is this realistic. or is Motocalc paint a rosey picture for me? :o
even if it is i think i'll test this setup out just to see if it is actually workable .. whats the worst that can happen .. i burn up a $6 motor? :D

qban_flyer
12-14-2005, 12:19 PM
ive been playing around with Motocalc. and these are what ive come up with for the power system im planning on putting in my GWS Zero.
the zero's AUW is around 13.5 oz. i may have to add some more weight to balance it out.. but this is its current specs. the motor is a brushed GWS EPS-350C with a C gearbox now if Motocalc is right 11.5 amps is not excessive for this motor and i wouldn't be flying it at full throttle all the time anyway. The motocalc version im using is the latest 7.09

Gear Ratio = 5.33
Diam (in) = 9.0
Pitch (in) = 4.7
Weight (oz) = 13.5
Batt Amps = 11.5
Motor Amps = 11.5
Motor Volts = 10.3
Input (W) = 118.3
InPLd (W/lb) = 140.4
Loss (W) = 37.3
MGbOut (W) = 81.0
OutPLd (W/lb) = 96.1
MotGb Ef(%) = 68.5
Shaft Ef(%) = 63.6
Motor RPM = 44372
Prop RPM = 8325
Thrust (oz) = 20.2
PSpd (mph) = 37.1
RofC (fpm) = 1736
Time (m:s) = 4:43


Is this realistic. or is Motocalc paint a rosey picture for me? :o
even if it is i think i'll test this setup out just to see if it is actually workable .. whats the worst that can happen .. i burn up a $6 motor? :D

I don't think GWS motors like over 9.6V of input (MAX), they have a tendency to fry very quickly at ten volts and higher. :D

The Great Planes 370 brushed box/motor affair will fly the pants off that Zero while drawing under 9 amps swinging a 10X3.8SF APC propeller using a three cell 1320 mil Li-Po. It goes vertical on me WOT. :)

MountainFlyer
12-14-2005, 11:35 PM
been sitting here testing/reading/thinking.. and here is what ive come up with so far for a power system for the Zero
its a toss up between these two brushless motors
a HiMaxx HC2816-680 with a 3C LiPo and a 9x6 prop
or a Hacker A20 22L with same batt and prop
both deliver around 20oz of thrust and are between 10 and 11Amps max draw and a pitch speed of roughly 45mph

any thoughts on these choices?

qban_flyer
12-15-2005, 02:11 AM
been sitting here testing/reading/thinking.. and here is what ive come up with so far for a power system for the Zero
its a toss up between these two brushless motors
a HiMaxx HC2816-680 with a 3C LiPo and a 9x6 prop
or a Hacker A20 22L with same batt and prop
both deliver around 20oz of thrust and are between 10 and 11Amps max draw and a pitch speed of roughly 45mph

any thoughts on these choices?

I like the Himax set up better. Both will fly that Zero like a speed demon WOT! :eek:

Have you considered Hobby Lobby's Esskay 400XT ($29.90) mounted on the E-Flite EFLM1915 stick motor mount adapter? With a three cell and an 8X6SF APC propeller it will deliver in excess of 19 0z of thrust (9-10 amps) and still fly the Zero like a speed demon WOT while saving you a few $$$! :D

http://www.hobby-lobby.com/brushless-skatty.htm

http://www.horizonhobby.com/Shop/ByCategory/Product/Default.aspx?ProdID=EFLM1915

MountainFlyer
12-15-2005, 05:31 AM
Qban Flyer

Ive been looking at the Esskay 400XT also but wasn't sure because i hadn't seen too much on it

qban_flyer
12-15-2005, 02:38 PM
Qban Flyer

Ive been looking at the Esskay 400XT also but wasn't sure because i hadn't seen too much on it

Morning MountainFlyer,

The link below will take you to all the threads including the 400XT (Hobby Lobby's, not the copy cats) here at Watt Flyer.

You will notice that the motor gets extremely high marks for perfomance and of course, its PRICE. Hobby Lobby had a sale that ended 12-13-05 where the 400XT was being sold @ $19.90. They have those crazy sales at least once a month! :D

I currently have a total of eight of them sitting aside and two in use as I can't pass up a good deal :eek:.

Three other guys at the Fulton R/C E-Aerodrome have also bought multiples of the 400XT :D. It's an incredible motor. :)

L8R :)

http://www.wattflyer.com/forums/search.php?searchid=43713

MountainFlyer
12-20-2005, 07:17 PM
Qban Flyer,
I ordered the 400XT and the mount ( got the mount today )
one question about the down angle of the motor on the zero. how much should it have?

Thanks

qban_flyer
12-20-2005, 08:49 PM
Qban Flyer,
I ordered the 400XT and the mount ( got the mount today )
one question about the down angle of the motor on the zero. how much should it have?

Thanks

Since mine came with the GWS box and was assembled as per the manual, all I did was to cut the stick to size when fitting the 400XT and EFLM1915 adapter so the propeller would not be sticking out too far forward in front of the cowl.

If I had to build another one, I would eliminate both the down as well as right thrust from it, or reduce it to no more than one degree in each direction.:)