See...i have repaired many tower pro motor and i have seen that the winding is done not with a single stand of wire but with two or three parallel running wires.....the word "thumping" what you have used is normally due to faulty winding wire, you will notice a continuous beeping also from the motor when it starts, vibrates and then stop....if you keep on throttle the motor and ESC will heat up.
REASON : if your motor had a crash, there are two possibilities
1. bent shaft
2. broken insulation in the armature (shorting the shaft and the winding in between somewhere) check with continuity tester

in case of tower pro, maximum time, the culprit is bent shaft
NOTE : bent shaft is visible inside the motor and not outside where you mount the prop. open the motor and then see..you will see a slight deviation in the movement once you manage to make the shaft straight your prob will be solved.
Sandeep

Quote from: sandeepm on July 28, 2010, 03:34:43 PM
See...i have repaired many tower pro motor and i have seen that the winding is done not with a single stand of wire but with two or three parallel running wires.....the word "thumping" what you have used is normally due to faulty winding wire, you will notice a continuous beeping also from the motor when it starts, vibrates and then stop....if you keep on throttle the motor and ESC will heat up.
REASON : if your motor had a crash, there are two possibilities
1. bent shaft
2. broken insulation in the armature (shorting the shaft and the winding in between somewhere) check with continuity tester

in case of tower pro, maximum time, the culprit is bent shaft
NOTE : bent shaft is visible inside the motor and not outside where you mount the prop. open the motor and then see..you will see a slight deviation in the movement once you manage to make the shaft straight your prob will be solved.
Sandeep

I can understand this about the crashed motor but then why the new motor and esc heating up? Also when the motor starts thumping, it stops & restarts like there is a lose connection again and again. As i wrote earlier it seemed fine without the mount. will post some pics so you can see the motor condition closely. i will also re-solder everything and check with/without mount in the evening when i reach home and post results.

It is always a good practice to use an ESC of average value, for example if your motor was designed for a ESC ranging from 25 to 35 amps, it would be good to use a 30A ESC, this because your motor manufacturers mostly test their motors without motor load, (without props)
if you are using a 25A ESC, remember that your ESC is in the limits of the lesser value that your motor was designed for, and if you check the ESC on a Ampmeter you will sometimes notice that they are less then mentioned value eg: 25A ESC will sometimes show less then 25A.(previous experiences)
So it is a best practice to always use a average value ESC.
Also check your cell compatibility while doing so.
Also remember that your towerpro 2409 motor has a RPM of 1600 and your battery is a 3C11.1v
so if we:
1600x11.1V = 17760 is more then the designed RPM of your motor!
try using a 7.4V x 1600 = 11840 combo!
this is lesser then the designed RPM of your motor, so overheating is not possible.
I hope this helps,

Dorwin

however triavial it may appear on the surface, here are few thumb rule that i always embrace, while dealing with marginl problems.
1. Focus  on ways to consistently being able to create the problem, than burying the problem.
2. Extremely important to play with one variable at a time.( for ex as Anwar said, do not do soldering+mount change together)
3. if able to  undo the last change and see if you can recreate the problem, that way we are 100% sure.
4. many times i have felt terms ;Allergy' and 'Loose contact' are synonymous wrt medical and electronics fields. both meaning a lack of enough understanding.


A wattmeter will appox cost USD20.00, link as follows:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=10786&Product_Name=HobbyKing_HK-010_Wattmeter_&_Voltage_Analyzer_

Most propbabaly, (as vinay said,) when the motor is mounted on the mettalic mount supplied,  pushing the motor well inside, the back portion of the motor shaft can touch/ rather press the wooden motor mount. Usually, a 4mm or more  hole is made there to avoid this.. If this is not done then it  can create considerable friction for the free running of the motor.




ashta

Quote from: anwar on July 28, 2010, 03:21:46 PM
If without mount it is running fine, then the mount is the issue... it must be restricting the free rotation of the some part of the motor.  Please check for that first, before trying to do and re-soldering.

Another thing to be taken in high consideration when choosing compatible cell+ESC+motor combos is that the difference in cell voltage reduces or increases the voltage drastically or on a huge amount.
this calculator may be of some help to you in getting the correct values, I haven't used it much but its worth a try!

http://dhrc.rchomepage.com/calc.htm

regards,

Dorwin

Quote from: controlflyer on July 28, 2010, 04:03:21 PM
It is always a good practice to use an ESC of average value, for example if your motor was designed for a ESC ranging from 25 to 35 amps, it would be good to use a 30A ESC
Dorwin

I think its the other way round. If you dont know what the motor/prop combo is consuming then its better to have a 35 Amps ESC on the safer side. Coz if a motor manufacturer recommends 35 Amps then its better the ESC be better 35 Amps. Anything less should be chosen only with a watt meter in hand, and doing a static test with a prop on ground at full throttle in the direction of the wind (not against). Also the motor consumes more current if you are closer to sea level. Its always better to have ESC bigger than the motor, typically with a 15 to 25% head room, so that even if there is less air flowing over the ESC, it can survive.

Just my 2 cents.

@CrazyPilot

If your motor is thumping, resolder the wire, other wise the motor may burn. Do not increase throttle when motor is thumping.

BTW how are you Ashtaji, its been so many weeks since we met. Will meet soon once I am free at jakkur.

Thanks for correcting me on this,
well it should be 30A up to 35A.
but, does efficiency decrease with the increase in Amperage?
My answer was based on the above statement, hence "average"

appreciate your point.

Dorwin

No, the efficiency wont decrease as its kinda pulsed supply, also if you use a bigger ESC the heat production is less hence more efficiency. The problem comes with the weight of the bigger ESC.

I get that!

Thanks for the knowledge sharing!

Dorwin

Quote from: vinay on July 28, 2010, 07:13:13 PM
No, the efficiency wont decrease as its kinda pulsed supply, also if you use a bigger ESC the heat production is less hence more efficiency. The problem comes with the weight of the bigger ESC.

And I switched from Glow to Electric because of all the mess . I think I will switch back to Glow engines soon . 

Buy a wattmeter and test on the ground.  Way to peace of mind/nirvana in leccies !

I second that Anwar!

watt meter is a primary requirement for electrics. Its just like your glow starter 

Ok guys. I am ordering a wattmeter. Will have to wait 3 weeks before i can test further.

Could you guys be so kind to chip in your thoughts on what else should be in my electric caddy? I will order all the things at once so i dont have to wait anymore. Kindly reply soon.

1) Watt meter with voltage analyzer
2) ?
3) ?

2) Extra Lipo.
3) ESC

Quote from: controlflyer on July 29, 2010, 02:57:44 PM
2) Extra Lipo.
3) ESC

Sir i dint mean 3 items only. was just illustrating. i need a complete list of items needed for electric flight.  

Add a lipo monitor, spare props, servo tester (not really required.)

Quote from: vinay on July 29, 2010, 07:35:25 PM
Add a lipo monitor, spare props, servo tester (not really required.)

ordered these and lot of other useful items. Thx

Dear Crazypilot,

My 2 cents...

a. If you do not have a wattmeter handy, you can always use a digital tong tester (available at any electronic shop for Rs. 250 to350.00). Put the tong tester encasing any one of the wires connecting the ESC to the motor for a brushless DC motor in AC current mode. This will approximately tell you if the current is increasing or decreasing and over a period of use you will know if there are any abnormalities. The values displayed does not exactly tally with the current drawn, but the change in current is significantly understandable. Plus you also have a simple digital multimeter to boot in the field.
b. For charging batteries with standard chargers, one has to either have a battery or a 12vDC source (for 3S LIPOS) with sufficient current ratings (about 5 amps plus). One can use a simple SMPS from a computer to get upto 10amps for 12v. The cost of the SMPS is around Rs.400.00. For field charging if one does not have a 12vDC based charger, one may have to have a "car inverter" which gives you 230v AC. This could become handy if you are also using a laptop computer etc at the field.
c. So a soldering iron and a glue gun would also become handy for quick repairs of planes with crashes. (Foam as well as corroplast based models)
d. What about a foldable chair-cum-table with umbrella... You know the ones one sees in one of the Tata Indigo ads. Cost about Rs. 5500.00 available at
Bangalore. .....Very handy this one... shade from the sun and rain while enjoying flying sitting down.
e. A LIPO checker... very handy in between flights to keep a close watch on the LIPOs.
f. Double sided tape... a must.. especially if you keep changing receivers and ESCs and /or LIPOs
g. Broad Cello tape... a life saver all told at any flying session
h. Squiver Sticks... the kind use in the kitchen... a neat way to strengthen foam/corro in the field.
i. Icecream sticks... needed strength when you want it for repair... not a must
j. A small bag of Rubber bands... can be used as substitute for o-rings if used wisely for a prop-adapter
k. EVOtite... a few tubes of Rs.25.00 each... best cynoacrylate that is available in Chennai for RC
l. .... shhh trying to think

I think thats it. I forgot to welcome you to the Electrics camp... no more wives screaming at screaming, oily, rattling, messy engines.

Happy flying...

Dear mpsaju,

Thx a lot for a detailed reply. I love this site and members who love to help others. now i will go as your list.

a-I already ordered wattmeter. i will also get a digital tong tester.
b-currently i use my B6 balance charger. it connects to my 12v ups battery too. your smps option is great but how will i balance charge the lipos using a smps. also whats the use of laptop on field?
c-i have soldering iron. will get a glue gun in future if budget allows.
d-now that's something to invest my money. although will have to wait long for a 5500Rs. chair.
e-lipo checker in stock
f-double side tape in stock
g-diff size tapes in stock
h & i- i dont know how to use them.
j- rubberbands & o rings in stock
k-where to get evotite?
L- ok

Thx again

Crazypilot,
hi,
i noticed somewhere u mention that the problem was when u put the motor on the mount, Check motor mount bolts, they may be a shade longer than necessay and may be fouling with windings. File the tips a mm or 2 mm off, if she works fine without the mount, nothing wrong with ur motor,
Rameh Tahlan

Quote from: rameshtahlan on July 31, 2010, 10:32:52 AM
Crazypilot,
hi,
i noticed somewhere u mention that the problem was when u put the motor on the mount, Check motor mount bolts, they may be a shade longer than necessay and may be fouling with windings. File the tips a mm or 2 mm off, if she works fine without the mount, nothing wrong with ur motor,
Rameh Tahlan

I second that...
even though i a newbie to this hobby, ur different combination and results clearly indicate there is a problem with the mounting and not the motor/esc!!! Afterall they work fine with your other mount!

The screws are a good point

or u changed from stick mount to X mount, did ur side mount have heat shield? Cooling is less in Xmount. seniors please correct me. On that, one ques from me arent some motors made so that they require air flow thru them for cooling? while some(maybe the same) require some gap at the back for air-flow?

or like Vinay said the new mount is hampering free movement, will making a small depression at the back in the wood(were u mount) help?

Quote from: CrazyPilot on July 30, 2010, 09:05:18 PM
b-currently i use my B6 balance charger. it connects to my 12v ups battery too. your smps option is great but how will i balance charge the lipos using a smps. also whats the use of laptop on field?
h & i- i dont know how to use them.
k-where to get evotite?

IF you do FPV (First Pilot View) as in  you have a camera on the plane alongwith a telemetry transmitter and GPS, you could get the feed from the camera on line via a ground receiver and antenna to your laptop and fly as though you are sitting in it as a pilot would. You could go to very high distances ... as far as  two or three kilometres and still control it very accurately within the range of your transmitters. This is advanced RC modelling for you... like the drones from US

As to Evotite, very similar to super glue but best suited for filed repairs

Saju

Saju ,
I  Like that   but  FPV is not too common a form of flying .
I think the fact that  we do it every weekend ( flying a couple of Kms and back  ) seems to have kind of rubbed off in you listing FPV equipment as essential for Electric flying   .

Crazy Pilot ,
FPV is not essential for flying electric .

We normally get evotite from landmark Oddesey  or similar shops.



Sai