Steve Collins

My Feedback: (8)

I am aware of the prop recommendations for this motor with the largest recommendation being 14 X 10. I am using two of these motors on a new Hangar9 B-25 and I am using 14 X 7 Master Airscrew, 3 blade props. I will be using 5 cell, 30C, 4500mah lipos. ESCs are 60amp Eflite.

I know there are considerations for amps and watts. Although I fly electrics exclusively, I really don't understand the amps vs watts thing and I have no equipment to measure either so please keep this in mind when replying.

My questions are simple:

A. Is this "over propping" the motor?

B. Any drawbacks to this setup?

Steve Collins

My Feedback: (8)

Anyone?

flyinwalenda

My Feedback: (5)

That is too much prop for the set-up.
I have some Power 46's on seaplanes and run MAS 12X6 3-blade props with a 60a esc running 5-cell 3850 30c packs. They have more than enough torque to rise from the water and fly aerobatics with about 8 minutes run time .
To convert from a 2-blade to 3-blade prop you need to reduce the diameter by 1" and then possibly keep the same pitch or reduce it.
You should really invest in a Watt Meter. It will tell you at a glance how many amps, watts, volts you are drawing from your set-up when experimenting with different props.
I would recommend using some MAS 12X6 3-blade props. A larger prop like a 12x8 or 13x8 will probably put you over the 60a esc limit so if you want to run those sizes I would upgrade the esc's to 80 amp.

You can also try this:
http://www.ecalc.ch/motorcalc.php?ecalc&lang=en

Steve Collins

My Feedback: (8)

Ok. Tested the Master Airscrew 14X7 3 blade props using a watt meter and they were way too much for this motor. I eventually settled on an APC 2 blade 13X8 prop. This had the amps at 55 and the watts a little over 1,000 at full throttle (5 cell 4500ma).

This now leads to another question. In some places the specs say this motor is good for models that need up to 950 watts of power and other places say 800 watts of power. Since full power with the 13X8 prop produces a little over 1,000 watts, will this wattage figure damage the motor?

jofro

Hi, great motor, I got one in my large 3/D depron foamy (150x175cm) I have built 5 years ago as a cross between 'pattern and 3/D' performer. I run it on 5S/4-4.5Ah packs with 100A ESC using 15x6 wood prop. I have done over 1000 4-5min. flights, in my memory twice in the salt water while during hovering torque rolls the alloy spinner with the prop took off vertically from the motor shaft. These things happen if you don't tighten up the spinner on the regular bases. After quick wash and some lube I was back in the air just about the same day. My model is only 1.8-2kg AUW and after prolonged hovering I find the motor gets pretty hot but so far so good, Cheers J.
(pic. added, model bottom right)

jofro

Another pic of the 46 motor with my 15x6 prop, just checked my logs, 1230 flights to date. Another pic is of 32 size I have in smaller model, a real battle ship so far well over 2000 flying sessions. I use also 10 size in much smaller model I have been flying the longest, still going after numerous salt water crashes in my earlier days while learning 3/D over the ocean, J.

Joseph Frost

Long time no hear, the Ultimate giant with its 46 power still going, now close to 3000 flying sesions in my pocket, after lot more dramas and joy to date sinse the ast post.

Joseph Frost

Good old EF46 in another action off the bush strip. (Giant 46 powered Ultimate)