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-   -   Does 3D Prop size matter? 130g Motor at 14x7 for 3D HobbyShop EPP Yak 48" (http://www.rcuniverse.com/forum/foamies-rc-electric-foam-aircraft-162/11123370-does-3d-prop-size-matter-130g-motor-14x7-3d-hobbyshop-epp-yak-48%22.html)

GizmoMadMax 06-18-2012 10:31 PM

Does 3D Prop size matter? 130g Motor at 14x7 for 3D HobbyShop EPP Yak 48"

If I want to have enough torgue to 3D this LARGE monster foamy that weighs 40oz, does it matter if i buy a motor that gives me 65 to 70oz in a small prop vs a larger prop???

My assumption is the bigger prop gives more air over the wings??

It seems, 3DHS has an Omega 130gram motor ($60) for it, and that sucker swings a much larger prop than any other supplier i can find...????

The Omega 130g swings a 14x7 with a 3S or a 12x6 with a 4s, wow, big prop...?
vs. a motor I already have in my stock (BP 2820/6 ), that swings a 10x7 on 4S & 12x6 on a 3S both at close to 60 to 65 grams of thrust.

>> If the Omega and the other brands both have the same torgue, does it matter the prop size??

It seems that every other supplier that has a motor around 130grams swings a much smaller prop.... Why is that?

NOW, for some reason, 3D Hobby Shop does NOT supply the torgue specs for any of their motors, which really stinks?
> Does anyone know the torgue of the Omea 130gram ?

Thank you in advance!!!

rmenke 06-20-2012 03:22 PM

RE: Does 3D Prop size matter? 130g Motor at 14x7 for 3D HobbyShop EPP Yak 48

You need to learn what size motor you need to do what starting off. First, just how much motor do you need? Useing weight as a basis is my mort used method. Ok, common smarts say yoiu need 4s0 oz of thrust to hold your airframe in hover. But, you need more power to pjull out of a gioof up. Decide how must thrust you are going to shoot for leaving say 20% for over rating, which most manufacturers do. Most great 3D pilots will suggest 2 to one, some as far as 3 to 1. So 40 oz X 2 = 80 oz 0 oz.Add. 20% ending with 96 oz of thrust needed. If you have something near that, say 90 to 140 oz. Try it, you can always exchange a stronger motor. If the suggested prop for the motor is say 12X6, start with a 12X4. Lower pitch will draw less watts and slow things down a Little, advantage pilot. Always check pour motor-prop decisions with a watt meeter, alwas, always!! I always use a 4 or 3.5 pitch prop to slow things down. ( really old guy) If you really want to check things out, tie a fish scale to the aircrafts tail and run hur up. Enjoy

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