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kc10boom
10-18-2005, 04:30 AM
Here is what I have:
Himaxx outrunner 2808-0980
Phoenix 35
10X3.8 prop
TP 3s 1320 mah 13c
Astro watt meter

The watt meter reads:
133 watts (motor manual says this motor is rated for 110)
12 amps

This is the set up the LHS recommended for my yardstik. I think that according to my meter the motor is putting out too many watts. It is smoking hot at full throttle. After owning the stik for a while I WANT TO TRASH IT! I did buy a MM Magpie last week. I want to use this set up in it. I think from my math work it should work good, maybe with a smaller prop. This is where I need some expert advise. Please advise me electric guru's.

roccobro
10-18-2005, 06:40 AM
Do you know what the amp rating for the motor is? Why do you want to trach it? What is smoking hot, the motor, ESC or mter?

It really sounds like you have the wrong prop for it. How does the plane fly with this prop? do you ahve any other nubmers like rpm?

Maybe try a smaller prop with a higher pitch and see how it does. I don't know what the yardstick calls for, but maybe a 9x5 or 8x5 should drop the amps a little and make some more static thrust . I use a 10x6 on my GWS SS with a chinese "Tower Pro" 1260kv motor. But if your overworking the motor, you'll need a bigger one or one of a different Kv to match the prop the plane needs to use. I'm not well versed in Himax outrunner motor either. :( A couple of props are cheaper than a new motor or plane.

Justin

qban_flyer
10-18-2005, 07:27 AM
Here is what I have:
Himaxx outrunner 2808-0980
Phoenix 35
10X3.8 prop
TP 3s 1320 mah 13c
Astro watt meter

The watt meter reads:
133 watts (motor manual says this motor is rated for 110)
12 amps

This is the set up the LHS recommended for my yardstik. I think that according to my meter the motor is putting out too many watts. It is smoking hot at full throttle. After owning the stik for a while I WANT TO TRASH IT! I did buy a MM Magpie last week. I want to use this set up in it. I think from my math work it should work good, maybe with a smaller prop. This is where I need some expert advise. Please advise me electric guru's.

I'm glad to see you are going to remove that set up from the Y/S. It's a miracle it survived that much thrust. Crappy little plane, though a good looking one. I'm on my third one, I like the looks so much, though its landing gear is as weak as can be.

Regarding your battery/motor/ESC/prop combo. I would suggest to go to a 9X3.8SF APC propeller if you are going to be using three cell Li-Pos. That outrunner is supposed to use a 10X3.8SF with a two cell pack, not three. The reason your motor is running hot is because the propeller is overloading it due to the three plus additional volts input from the additional cell.

Try a 9X3.8SF and check your current draw again, I'm sure it will be within the range recommended by its manufacturer and things will cool off considerably. Motor will last longer too.

roccobro
10-18-2005, 07:32 AM
And there you go. Ask and ye shall receive!

Justin

kc10boom
10-18-2005, 03:02 PM
Thanks for the info, I sort of thought that a smaller prop might be the ticket. I am new to electrics, but I am trying to go first class. I agree that the Yardstik does look good. That is why I bought it over the Slow Stick. But look good is all it does, I wished I would have bought a SS.

falingtrea
10-18-2005, 04:33 PM
Here's a website with a nice little motor calc program. You can play with a setup and see how different parameters affect performance.

http://adamone.rchomepage.com/calc_motor.htm

qban_flyer
10-18-2005, 04:46 PM
Thanks for the info, I sort of thought that a smaller prop might be the ticket. I am new to electrics, but I am trying to go first class. I agree that the Yardstik does look good. That is why I bought it over the Slow Stick. But look good is all it does, I wished I would have bought a SS.

I have both. One for looking pretty at the field and fly a bit as it doesn't like to be tossed around. It gets flown in calm weather in the mornings and evenings exclusively.

The ugly duckling (S/S) has over three hundred flights under its wing as it gets flown in all kinds of weather. Ugly, YES. Sturdy, ABSOLUTELY indestructible! The only S/S I have seen totalled was after it collided with a light pole at a park nearby. Light poles are not in the habit of moving out of the way of incoming R/C models regardless of how ugly the plane is.

qban_flyer
10-18-2005, 04:53 PM
Here's a website with a nice little motor calc program. You can play with a setup and see how different parameters affect performance.

http://adamone.rchomepage.com/calc_motor.htm

Great site. Thanks for making the link available to all.

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