71" Cub/46Pro/Which Prop?

Got this fabric covered Cub. Will be underpowered with the 46 Pro but wondering which prop to put on it for pull,not speed. Have been running a 61 4S but it bit the dust and the 46 is on the shelf and needin' a home. Which prop???

Reply to
TX_QBALL
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That's an understatement. Use a 10-4 or 11-4 prop. Fly it on the wing.

Good luck! Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

According to my chart, the lowest pitch props for that size are a 10x5 or an

11x4. They go for like $2.50 apiece so experimenting shouldn't be cost prohibitive.

Steve.

Reply to
Steve Banks

Good luck for sure. A 10-4 is too small for a milquetoast .25, and you want him to put it on a hot .46? A Cub screeching like a pylon racer at 20K and going nowhere prolly isn't what he wants. TXQB - Try a minimum size of 11-6; 12-5 or 12-6 prolly better. A good .46 2S should produce more power than the .61 4S it replaces even at turns in the 11-12K rpm range.

Abel

Reply to
Abel Pranger

I don't think it will be underpowered, but that is just MY opinion.

The Hangar 9 EIGHTY inch Cub flies quite well on a Saito .56, so your smaller bird should do well on a .46 two stroke. Try an 11-5 prop to get the max from the engine and enjoy the results.

Reply to
Six_O'Clock_High

On Wed, 08 Dec 2004 18:52:43 GMT, "Six_O'Clock_High"

I have a 12X4 Zinger on my Goldberg Anniversary with a TT Pro .46. Flies just fine!

Dan

Reply to
Dan

Actually, the 10-4 may be a little too small for a (hot) .46. However, it's an excellent prop for an FP- or LA-type. I typically run 10-4s on O.S. .32 and Webra .32, looking for power not speed.

If the prop diameter is too large, it will load the engine so much that it won't make enough RPM for the pitch to pull the plane at flying speed.

Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

Reply to
Nick Hille

The chart I saw says a .45 can use up to an 11x6. In this application though Q-Ball is replacing a .61 with a .46, since that is what he has. So he probably wants to "gear it down" a bit by using a lower pitch prop.

Reply to
Steve Banks

I second that. mk

Reply to
MK

I would say for a Cub on the 46 that an APC 11X5 or so would be a good choice.

Reply to
Paul McIntosh

On that basis I am seriously "over propping" my engines.

I regularly use a 10 x 4 on a .15 engine in a semi scale Fournier - 72" span - flies in a very scale like manner.

On a "cooking" 40 I go up as far as a 12 x 6 with no problems. The models fly well and produce much less noise than if I use the normally accepted 10 x 6.

Malcolm

Reply to
Malcolm Fisher

The TT .46 Pro does well with a 11/4, but turns about 14,000 RPM which would sound a bit strange on a Cub.

MK wrote:

Reply to
Sport Pilot

I agree with the posters that advocate the larger props. Lots of experience to support it too, reducing noise levels.

10x6 is a smallish, but still quite normal size for a .40, 10x7 for .45. To go up one size in diameter greatly increases prop efficiency, without unduely loading the engine.

Target rpm between 12000 and 13000, using a 11x5 or 11x6 prop would suit that plane like a T. Maybe if the motor-exhaust system is up to it, an 11x7.

RPM over 13000 just beat the air, which for some is identical to getting most fun out of it. It's hard to argue 'bout that. "Sport Pilot" schreef in bericht news: snipped-for-privacy@f14g2000cwb.googlegroups.com... The TT .46 Pro does well with a 11/4, but turns about 14,000 RPM which would sound a bit strange on a Cub.

MK wrote:

Reply to
warchild

I have the 71 in. Cub and use a Saito 40 and an 11/5 prop. Works fine. carl Anderson

Reply to
carl anderson

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