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Twmaster
09-12-2005, 01:54 AM
I know somewhere along the way I saw a basic rule mentioned about weight to watts when it comes to converting a slimer to E-power and I for the life of me cannot find that info again. :confused:

One reason I ask is that I have an Ace Simple Extra. It was flying something like an .051 IIRC. The empty airframe is 12 ounces with aluminum landing gear. I'm thinking an AXi 2208/34 with a 9.4 prop and 3S 1130 Lipo for power. (somewhere around 65W). AUW is estimated at 19-21 ounces.

I understand the Simple series fly well but fast on a DD SP400 and 8 cells.

Any guidance? Pointers to relevant posts elsewhere? Lotto numbers? (kidding! :))

TIA!

Mike Parsons
09-12-2005, 02:20 AM
Below is a snipit that displays my ROT. Note that these are watts in and not watts out, but it has served me well in my conversions.
That setup should yeild you about 16-18oz of thrust. Should be a good sport flyer. If you havent bought the motor yet, consider a 2212/34. Swinging a 9x4.7 for a bit over 9 amps and 26 oz of thrust. A 2808 would be even wilder.

Lotto: 22-34-12-45-16 powerball: 21 :)


http://www.wattflyer.com/forums/showthread.php?t=1093

The rule of thumb that I use is 85 watts/lb for ROG, 100 watts/lb for good sport/acrobatics, 115-125 watts/lb for good 3D and 150 watts/lb + for insane performance. These numbers will remain the same regardless. However it is the starting point for me to figure out what my watts need to be (or I desire them to be).

Matt Kirsch
09-13-2005, 05:24 PM
6 13 17 29 46 51, supplemental number: 42

IMHO, you will not be happy with only 65 Watts on a 21oz plane, especially an Extra. Glow conversions should be made with a minimum of 90 Watts per pound, preferably more, to get glow-like performance. You want an Extra to fly like an Extra, after all, not like a GWS Tiger Moth...

Jump up a size on the motor and battery. Go with a 3S ThunderPower 2100, or a 3S Kokam 1250 (15C) to save a couple ounces. Use the AXi 2808/24. Your all up weight won't be much different, but the plane will definitely fly with authority.

GeraldRosebery
10-02-2005, 05:30 PM
I know somewhere along the way I saw a basic rule mentioned about weight to watts when it comes to converting a slimer to E-power and I for the life of me cannot find that info again. :confused:

One reason I ask is that I have an Ace Simple Extra. It was flying something like an .051 IIRC. The empty airframe is 12 ounces with aluminum landing gear. I'm thinking an AXi 2208/34 with a 9.4 prop and 3S 1130 Lipo for power. (somewhere around 65W). AUW is estimated at 19-21 ounces.

I understand the Simple series fly well but fast on a DD SP400 and 8 cells.

Any guidance? Pointers to relevant posts elsewhere? Lotto numbers? (kidding! :))

TIA!

a 3S 11.1 volts 1100 mah pack should be able to produce about 110 watts unless its an older design LiPo. At 110 watts your plane should fly OK. Just increase the prop pitch until your draw 110 watts. Use a watt meter.

Twmaster
10-02-2005, 05:37 PM
Thanks Jerry. Have Astro Super Whatt meter. Can travel! ;) Honestly thanks for the sanity check! The only component I need to acquire will be a new 3S pack. Methinks a nice 20C Kokam will do the job!

Mike Parsons
10-02-2005, 06:16 PM
Just remember that nothing comes for free and that includes running a pack at its highest C rating. The price you pay for that is flight time.