| Image Comments |
| VP46 | 09-Feb-08 02:01 |
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| jgood | 09-Feb-08 07:42 |
| Looking very nice! When in the maiden flight? |
| VP46 | 09-Feb-08 13:32 |
| I seem to have burned out the motor - To much fun Taxiing around I suppose. I added Stripes and the Guillows Decals last night.....will post more pics on Monday (left the camera cable at work).
Maiden flight should have been this weekend - AUW is 4.5 OZ Hardly the 3.5 oz of your fairchild - which BTW was the inspiration. Saw your Youtube video and used the credits to build my power system ;)
I think it will fly - I added Washout to the wings last night - an idea I got from Konrad in another forum.
Thnaks for noticing----its my first one in over 20 years! |
| tditerlizzi | 09-Feb-08 14:21 |
| I see you are reading the Spiderwick Chronicles...did you enjoy it...getting ready for the movie next week...oh yeah, the plane looks super too |
| VP46 | 09-Feb-08 14:26 |
| MY 6 yr old says his favorite is book 4 - he can't wait for the movie! |
| VP46 | 10-Feb-08 10:54 |
| This may not be the correct forum for this but......if I taxied around for 10 mins or more and then at the end of the charge ran the motor at FT, would that be enough to burn it out?
I ordered two replacement motors at $8/piece from radical R/C.....can I expect to go through a lot of motors with the GWS setup? |
| harve | 10-Feb-08 12:30 |
| What is your power set-up? The only thing I can think of is exceeding the voltage req. of the motor: http://www.gws.com.tw/english/product/powersystem/lps.htm |
| jgood | 10-Feb-08 13:50 |
| Your battery sounds fine to me. I don't think I've ever burnt a motor out, only worn them out. And they certainly don't wear out in 10 minutes. Did you have a prop on it when you ran it at full throttle? What happens when you try to run the motor now? A little wash out is definitely good. What about balance, are you balancing as per the plans? |
| VP46 | 10-Feb-08 14:37 |
| I did have a prop on it - Nothing happens now its as if it is not conected . The servis have power but I get nothing from the motor.
Note Worthy: I tried to run the GWS setup with the 100li GWS esc and my old 3 channel cheapy radio. It didnt run the motor and smoked the ESC. I took it back to Aeromicro (a few miles from my house)and he called the motor Dead on arrival and replaced the ESC and motor. Then promptly convinced me to buy a new futaba radio.
Ebveything was fine ran the battery down after that 10 min taxie run and charged the battery back up. Then nothing from the motor...The Cowl was not vented and it did get warm - I just assumed I burnt the motor due to heat. I have since fixed the ventilation.
It's the lack of ventilation and heat isn;t it? |
| jgood | 10-Feb-08 14:49 |
| Do you have any other motors laying around that you can plug into the ESC? I really don't think it would be heat that would do that. Extreme heat maybe, but I don't see why you would have generated that kind of heat at 7.4V with that tiny pack. The ventilation would have been fine, my Fairchild has almost none, and that runs OK. I hope the ESC is OK. The ESC doesn't have a safety mechanism whereby it won't start the motor until you move the throttle all the way up, and back down again, does it? Some of mine have that. |
| jgood | 10-Feb-08 14:51 |
| One other thought - the ESC probably will not power the motor if the battery voltage is too low. Maybe it didn't charge? The ESC will still power the servos, even if it thinks there is not enough voltage to power the main motor. |
| SteveM | 10-Feb-08 16:56 |
| You can also test the motor with a multimeter (if you have one). An open circuit (infinite resistance) or a short (no resistance) would indicate a damaged motor, you should see a resistance of about 10 ohms across the LPS-B2C. If you don't have a multimeter then maybe see if the prop shaft spins freely then connect the battery directly to the motor to see if it will run.
Which gearbox do you have, the A, B, or C? Which prop is it? A prop too large or too small can effect the motor. |
| VP46 | 10-Feb-08 19:08 |
| Just tried hooing up the motor to the batt directly - nothing until I spun the prop by hand with it hooked up and it worked very slowly.
This is what happened last time only the plastic around the ESC was split. Its not split now and runs the Servos.
I charged the Batt unit the Light on the GWS charger went all the way off. I actually tried charging it again thinking it was the low voltage issue - I'm charging it again now. Fingers crossed but I think there must be an issue with the motor. The prop is the 7060 which is matched to the LPS B2C drive/motor.
Is it possible I have two bad motors from Aeromirco in a row? |
| VP46 | 10-Feb-08 19:16 |
| Batt is most liekly fully charged - Blue flashing light doesn;t even com one and the servos move with Authority....I don't have an extra motor untless you count the cheap 300 and 400 in my ARF's.
BTW - I'm so confident that this model will fly..I can almost taste it :) |
| VP46 | 10-Feb-08 19:21 |
| Oh and yes the Prop does spin freely.
Thanks for helpping trouble shoot this - I'm 90% certain its the motor. You could smell it just now after turning slowly direct connect to the batt. Also, please excuse the Typos - - typing fast as my wife is bugging me to go to the Grocery store. |
| SteveM | 10-Feb-08 19:57 |
| Since it spins freely but turns slowly when powered up, I am going to guess that the windings are shorted somewhere and causing a large current draw but little magnetic field with which to turn the rotor. Unless you have a multimeter it is difficult to troubleshoot accurately. If you have one, check the motor resistance, battery voltage unloaded and loaded, and the current being drawn by the motor. And if you are using a lithium polymer battery don't drop below 3 volts per cell or it will be irreversibly damaged. |
| VP46 | 10-Feb-08 20:19 |
| I need to get a multimeter. Anyway to "eye" 3 volts with out one?
The short on the motor concept is wierd - I literally taxied it twice.....lobbed it a few feet off the ground only to nose dive on the lawn and break the motor mount and bend the motor shaft.
I fixed the mount and the shaft - taxied it around for that last 10 min or so run....then it decides to short? Makes no sense to me - but I suppose if its not heat damage then it must be something is shorting. |
| VP46 | 10-Feb-08 20:21 |
| The Battery BTW is an etec 7.4 volt 300 HP - not sure what the HP stands for. bought this over the 7.4 250 mah becuase they were out of them.
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| SteveM | 10-Feb-08 21:09 |
| Put four alkaline cells in series to get 6 volts, then hold the leads to your tongue. Then compare the strength of the jolt to the one from your plane's battery pack. I guess instead of your tongue you could use the brightness of a light bulb for the comparison.
The EP7060 prop appears to be matched to the 'C' gearbox with a 6.2:1 gear ratio. If used with the 'A' gear box (4.0:1) it would draw more current and would make it easier to overheat the motor and melt the wire insulation in the windings. Regardless, it is hard to say why your motor died, let's hope the new one works better. |
| VP46 | 10-Feb-08 21:49 |
| hah, a multimeter would be easier ;)
Fingers crossed the new motor sorts it - I'll be bringing to Aeromicro tomorrow, he has some kind of fancy multimeter that meters the voltage? Amperage? as it is hooked up inbetween Batt/ESC/Motor. It's pretty trick whatever it is. |
| VP46 | 10-Feb-08 22:10 |
| Yikes your right - I'm using a prop that appears to be ill matched - - - James? You were using this configuration wern't you? |
