FrancisPerson

I am in the process of building a Clancy Aviation Turbo Bee. If I had the cash for a Li-Po charger and batteries it would be electric; but I don't, so I plan to use my MP-Jet .061 R/C Diesel. The numbers are:

APC 7x5 cut down to 4.125" --- 18,300 RPM

APC 8x6E cut down to 4.125" --- 13,500 RPM (very wide blades)

Grish Magnum 6x4 3 blade cut down to 4.125" --- 18,000 RPM

(For referance an un-cut APC 7x3 --- 15,200 RPM)


How will my Turbo Bee fly ? -- AND -- Andy Clancy recomends the cut down APC 8x6E prop with a speed 400 6V motor on eight cells. What RPM does this generate????????????

Francis

Dan Vincent

Francis,

Just curious, does that muffler extension rob any RPM. How quiet is it?

FrancisPerson

Dan Vincent,

The "muffler extension" is simply heater hose to keep the Diesel goo at bay. With a id of 3/4" there is no restriction and the numbers are with the "goo protector hose" in place as you see.

G-d Bless America

Francis Person

FrancisPerson

I know the subject line is "MP-Jet" but this is a Turbo Bee question.

Any Help??

Thanks

Francis

DICKEYBIRD

Hi Francis, I'm neither a 'Bee or a diesel expert but I am familiar with that type of big, slow plane. Why do you want that small a prop dia. with a diesel? The slower turning, big fan up front would seem more logical to me than a tiny little screamer. Isn't the diesel's forte pulling big wood? Not being critical, just curious.

ZAGNUT

My Feedback: (1)

DB, the turbo bee has the engine stuffed inside the fuselage ducted fan style.

Francis, there was a thread here some time ago with lots of pics and info. maybe you can edit the subject line of your original post and get some more responses from those in the know



dave

DICKEYBIRD

Doh!! Thanks Dave....now I understand! I'm a little dense sometimes.

FrancisPerson

I bought a MEGA 16/15/4, Castle Creations Phoenix 25 and FMA 3s1p 2100mah LiPo batteries for my Turbo Bee project.

The electric setup gave the following RPM numbers

APC 7x5 cut down to 4.125" --- 20,000 RPM @ 17.5 amps

APC 8x6E cut down to 4.125" --- 17,850 RPM (very wide blades) @ 27 amps

For reference a MP-Jet 1cc diesel turned these same props at

APC 7x5 cut down to 4.125" --- 18,300 RPM

APC 8x6E cut down to 4.125" --- 13,500 RPM (very wide blades)

I plan to use the cut down APC 7x5 as it moves a lot of air and the current draw does not exceed the current ratings of the motor and speed controller

What about your Turbo Bee?

Francis

Alan Hahn

Francis,
When I look at your results, I wonder if the diesel MPJet using the cutdown 7-5 prop might work better than the electric version. The reason I say this is that the wweight difference is considerable between the 2 power options. Your battery alone weighs about 5oz, and is by itself, heavier I bet than the MO-Jet +fuel.
I will say the electric is a lot cleaner, nothing to cleanup inside the fan unit.

DeviousDave

As you found, the MP JET is timed a little too wild for your application. The electric will be faster and a better performer than the raw numbers you got suggest because ducted fans unload a lot and the electric setup won't have breathing difficulty when the rpm goes up.