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rv9flyer
10-28-2009, 09:16 PM
Hi Guys,

I have some problems with the setup/motor its running fine when its running but the startup is bad... Its going forward backward forward......
I tried a different battery and a different speed controller but still the same problem. Also changed around with the timing setting but no difference. When i take the prop of its going a little better but still not the way it should be.

Maybe the video makes it clear:
http://www.youtube.com/watch?v=erewC9Hg-50
(no link yet sorry need 3 posts first)

This is my setup:


TGY AerodriveXp SK Series 35-36 910Kv
Mystery 40A Brushless Speed Controller (Blue Series)
ZIPPY Flightmax 2200mAh 3S1P 20C

rv9flyer
10-28-2009, 09:18 PM
Post 2

rv9flyer
10-28-2009, 09:18 PM
post 3

rv9flyer
10-28-2009, 09:19 PM
Here is the video:

http://www.youtube.com/watch?v=erewC9Hg-50

texasclouds
10-28-2009, 10:01 PM
is that one of those hobby city $16 motors? i don't have any experience with them, but my guess is that is just something you may have to live with.

i had a 1/10 scal truck brushless system that did that. it was unsensored, and didn't 'know' where it was to start moving.

texasclouds
10-28-2009, 10:08 PM
sensored/sensorless:

http://www.teamnovak.com/tech_info/brushless/sensor_vs_sensorless.html


more info:

http://www.rcuniverse.com/forum/m_1558046/tm.htm

http://en.wikipedia.org/wiki/Cogging_torque

check your batteries and connections:

http://www.wattflyer.com/forums/showthread.php?t=48054&highlight=cogging

MustangMan
10-28-2009, 10:11 PM
Do you have a different brand of ESC you can try?

While the motor may be giving the controller some difficulty, all our brushless motors are sensorless and the ESC startup sequence can't depend on feedback from the motor until the motor actually begins to spin. Usually the ESC simply outputs reasonable low-power drive signals to get the motor moving, and only then begins looking for feedback telling it how the motor is moving. If the ESC starts looking too soon it will likely get confused. Does the ESC have any "startup type" settings like "soft start". Trying different settings might lead you to a workable configuration.

rv9flyer
10-28-2009, 10:27 PM
Hi,

yes i tried a different brand esc and still the same thing. Also the slow startup feature i tried and samething there. Sometimes i takes up to 20sec to get the motor running.
I checked all the connectors/cable/soldering.

Any other tips?

texasclouds
10-28-2009, 10:38 PM
does the manufacturer have contact information? you may have to date a Chinese girl for a while to get it translated. ;-)

Dr Kiwi
10-28-2009, 10:57 PM
I was thinking that "fast start" might kick it into life.

Luckily I have hardly ever had these problems because the ESCs I have all seem to be good quality... Castle, Motrolfly, Markus etc.

I remember now.. I did test some HiModel or whatever they were called that week, and had no luck with them at all.

Mystery.. well-named.

rv9flyer
10-29-2009, 02:27 AM
I tried the fast start setting with no luck. Still same problem! whaa it drives me crazy! I tried another esc different brand. Same thing.

Can it be the motor?

rv9flyer
10-29-2009, 02:41 AM
I just tried it with a fresh fully charged battery and then the first 5starts are good and then the problem is coming back. All connector and cables are good.....

flydiver
10-29-2009, 02:57 AM
Have you tried a different motor with those ESC?
A motor that does the 'herky jerky' often indicates a bad connection. You say your connections are good but you have no control over the wires inside. These can go bad or short out giving you the problems you describe.

You've done most of the right steps. I suspect a bad motor.

smokejohnson
10-29-2009, 03:04 AM
+1 for a bad connection.

I was having this problem on a set up and although the solder joints between the motor and esc looked good I re soldered them and the problem went away.

It's worth a shot.

rv9flyer
10-29-2009, 03:26 AM
Okay thnx i have a look again. I use ec3 plugs between battery and esc are those good enough?

MustangMan
10-29-2009, 04:21 AM
Connections are indeed a good thing to check. I once had problems with a motor running erratically even though all solder joints were good. It turned out that the little springs in the ESC-to-motor bullet connectors were free floating on the contact pin and thus wouldn't make a solid connection despite the fact that it took considerable force to push the bullet connectors together. I finally figured it out after there was enough arcing to dis-color the contacts. I managed to VERY CAREFULLY add a TINY touch of solder to the tip of the bullet so that the spring part was soldered to the pin part AT THE TIP ONLY. The other end must have room to move otherwise the spring can't compress and you won't be able to mate the bullet connectors. It complete fixed the motor stuttering problem. Come to think of it, it was a Turnigy motor using the supplied bullet connectors.

rv9flyer
10-29-2009, 04:40 AM
Hi guys,

I opened the motor and i think i figured out the problem... there are 3wires going in to the motor. One of those is bad 3 small wires in side are broken...

The motor is from hobbyking you think they will replace it?

rv9flyer
10-29-2009, 04:51 AM
Its a bunch of small wires like 6 orso they are glued to the motor, but they are snatch of while they were twisting them in the process. Some Chinese was not paying attention!!

I try to make a picture tomorrow.

aramid
10-29-2009, 04:54 AM
They might replace it, but unless you live in Asia it's probably not worth it. Hobbycity will most likely require you to pay the return shipping, which would be nearly as expensive as ordering a new motor, plus you'll have to wait for their returns process.

Overall, I've had very good luck with Turnigy motors, although I had bearings go bad in one. If you'd like to try something different the second time around, take a look at Heads Up RC (http://www.headsuprc.com/servlet/StoreFront) - the prices aren't much higher, but shipping is $2 flat rate. The company is in Florida, and service is usually excellent.

rv9flyer
10-29-2009, 06:05 AM
Just ordered one there! Hope its coming fast! thnx guys

CarlosTomasso
11-02-2009, 05:21 PM
Hi guys,
I have a new e crusher brushless car, wich I used tree times. First I have managed to brake the upper arms, then no Idea what happend but my 12t brushless motor is cogging, overheating and the tree wires connecting the esc and my superb brushlesss are getting hot too after few second... I have charged my batt. full twice 5000mAh and3300mAh. no change. the car is not moving and I have taken the motor out from the car - same sound and result:( any idea wahat is wrong??


Many thx
Tom????:mad:

flydiver
11-02-2009, 05:56 PM
Broken/shorted lead inside most likely.

CarlosTomasso
11-02-2009, 07:16 PM
Many thanks, as soon as I finish work I will try to open the motor. thanks again - hope it will be something I can fix.

tom:roll:

flydiver
11-02-2009, 10:16 PM
That's likely a geared inrunner. You may want this for getting inside:
http://www.maxxprod.com/mpi/tips2.html

If you mount them with too long screws they can go inside and damage the windings.

If you do break a wire on an inrunner they are difficult to fix. I have soldered broken wires but not easily.
Double check all outside connections first, it's easier and may save you some trouble.

CarlosTomasso
11-03-2009, 12:11 AM
uff - well , nice link thanks, took away all my confidence:(


upseting 4-5 times used grrrrrr:(


cheers tom

flydiver
11-03-2009, 01:03 AM
Well, you got a few uses out of it.
For planes new fliers usually trash them within 10 seconds, AND keep doing it for awhile until their beauty is nothing but glue and tape.
Then they get to start over.

aramid
11-03-2009, 04:36 AM
A lot of the bigger inrunners used in cars and trucks don't have pressed endbells like the Himax Flydiver linked to. Typically they can be disassembled with a screw driver or Allen wrench.

Once you're inside, though, Flydiver is dead on. Good luck...

Wallygator
11-15-2010, 04:41 PM
:confused: Recently went through two new motors thet would not run at all. They both would only stutter and slowly cog over never gaining speed. Decided to troubleshoot the second motor and knew what the trouble was as soon as I removed the heat shrink from the bullet connectors. They looked like a 5 year old did the soldering and were greenish/white with corrosion. This particular brand had foregone using soft wire leads and had put the connectors directly onto the magnet wire. After removing the connectors and cleaning the wires and removing the insulation I reinstalled the bullets and retested. BadaBin BadaBoom motor now runs like a scalded dawg.
I have several other cheap china motors and they all have soft wire leads. I guess the price wars are starting to make them cut even more corners....????

texasclouds
11-15-2010, 04:46 PM
:confused: Recently went through two new motors thet would not run at all. They both would only stutter and slowly cog over never gaining speed. Decided to troubleshoot the second motor and knew what the trouble was as soon as I removed the heat shrink from the bullet connectors. They looked like a 5 year old did the soldering and were greenish/white with corrosion. This particular brand had foregone using soft wire leads and had put the connectors directly onto the magnet wire. After removing the connectors and cleaning the wires and removing the insulation I reinstalled the bullets and retested. BadaBin BadaBoom motor now runs like a scalded dawg.
I have several other cheap china motors and they all have soft wire leads. I guess the price wars are starting to make them cut even more corners....????


good to hear it is fixed!

i have a 3530-11 motor that runs the magnet wires all the way to the bullet plugs...they were slid through an oversized insulation tube to make it look like heavy guage multistrand wire...you can squeeze the tube and tell what is in there. works fine though :D

i've heard poor solder connections can create trouble for the esc...glad you found the error!