E-Motor Comparison

[Sir John]

I'm looking for a sourse of information about E-Motors, example:- Graupner refer to there Compact 350 8.4 V Motor, but I would like to use a different type/supplier.
Is there anywhere where I can find comparison data from one motor to another?
For any help, many thanks in advance.

[Alistair Taylor]

You could try either;

http://www.motocalc.com/

or

http://www.slkelectronics.com/ecalc/index.htm

Only neither of these appears to have test data for the Graupner compact motor you refer to.

You'd be best off calculating how many watts your model needs (75 watts per pound for trainer-type handling, 100 watts per pound for aerobatics, and 150 watts per pound for 3D), what cells (and how many) you're planning to use, what an appropriate prop size would be (is the model a pylon racer? if so use a small high revving high pitch prop, if it's a sport/scale/trainer - use a larger, lower revving prop with less pitch), and then phone John Emms at Puffin Models who will sort you out with the right motor.

HTH

AlistairT

[Giannis Tzanis]

Hi!!!

Iam thinking to use the graupner Compact 350  8.4V on a 2.6m saiplane.

Power: COMPACT 350

V: 8.4v

PROP: 10 x 6(GRAUPNER CAM SLIM PROP)

MAX. WEIGHT: APROX. 2.2Kg.

Well, is that possible or not? I cant find any info about input power, thrust, etc.

What is the max. input power for Compact 350? 

Best regards from Greece.

[Former Member]

[This posting has been removed]

[Giannis Tzanis]

No!!! Not at all.

The COMPACT 350 is an outrunner(Brushless) motor with maximum Voltage the 12V. It is allmost similar to the COMPACT 345Z, but a litlle bit stronger.If there is any one who test  it and have  info about this motor (Cells,Prop,R.P.M, Thrust, etc.) please let me know.

Giannis Tzanis.

[Alistair Taylor]

Giannis

I couldn't find any test data for the graupner 350 compact - and it's not listed in either Electricalc or Motocalc (online motor test software).

See; Fly Electric Motor Constants

This will (if you have the patience and the figures) tell you how your motor should perform.

However - it really is far simpler just to buy a tester, and set aside an hour to test your motor on various props, until you've narrowed your choices down to two or three of similar pitch/diameter. You can then test these in flight to se which "feels" right.

AlistairT

[Former Member]

[This posting has been removed]

[Alistair Taylor]

Like I use such calculations.....ever

Plug it in, fire it up, see if it smokes...... works for me

[Tim Mackey]

Heathen!

[Giannis Tzanis]

Sear fellows!!!

 It is much easier to use the MTG 2820-07 motor instead the COMPACT 350. It can handle allmost 500W.The data sheet from that motor gives,maximum model weight  2300gr(trainer). That means allmost 3000 gr. for a 2.5m glider. I got a simpler solutions in my hands, use the 2820-07 and leave the COMPACT 350 for my san. Do you agree?

Giannis.

[Tim Mackey]

Well I guess so, but really almost any 950Kv or so outrunner 30A motor would do fine

This for example is only £26 and 400Watt capable - and cheaper ones are availbale too!

[Erfolg]

You need Ron Van Sommeren, he did a calculation for me on a Tornado motor and gearbox. He was spot on. He is a whiz with calculations and access to spreadsheet programmes.

He recently posted a note on a 3m helicopter, if that helps you find him.

Erfolg

[Tim Mackey]

Well if all he needs is simply to find a motor which will swing a 10" prop on his powered glider, then he has the answer in the posts above. Simple really, choose from loads of suppliers who can offer an outrunner of around 900 -1000 Kv and handle circa 300watts. Finish.

The original thread starter asked for a comparison type programme, and he was given a couple of useful links by Alistair, then Giannis kinda hijacked the thread and away we went !