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Old May 19, 2010, 09:36 PM
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Originally Posted by JLH Racing View Post
The motor was 190deg F, Esc was at 135f and batt was at 92f.
My Question, are these new temps "OK" after a 20 minute run.
Much too high, anything over 200-deg on the motor is near catestrophic. By continuing to run as you are, without a drastic gearing change, is for the motor and even the esc to go up in smoke.
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Old May 19, 2010, 09:43 PM
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i'd only worry about the motor untill the esc get's worse, anything above 200 could demagnatize the magnets in the motor, which would result in a dead motor. the esc should be fine. like suc2sucminit said, get a heatsink, and if there's one available, try to get one with a fan on it. it will help even more.
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Old May 19, 2010, 10:29 PM View Post
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Old May 19, 2010, 10:31 PM
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actually it does. get your facts right. heat above 200 degrees can cause a motor to demagnatize and kill the motor.
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Old May 19, 2010, 10:35 PM
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It causes the expoxy to melt off the windings and then causes the motor to short out. All sorts of magnets survive just fine in high temps.
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Old May 19, 2010, 10:37 PM
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ignore the kid ura, or better yet report him for trolling. his hobby is getting in over his head in topics all over this forum, and most likely why this place is so dead.
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Old May 19, 2010, 10:41 PM
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Gotcha
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Old May 19, 2010, 10:42 PM
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it doesn't just cause epoxy to melt off. it causes a whole lot more.
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Old May 19, 2010, 10:44 PM View Post
cat_sammich
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Old May 19, 2010, 10:47 PM
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LOL
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Old May 19, 2010, 11:17 PM
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http://wiki.answers.com/Q/How_to_demagnetize_a_magnet

Methods to demagnetize a magnet

There are several ways to demagnetize a magnet: high temperature, AC magnetic fields, mechanical shocks, and physical distortion.

If we heat a magnetic material above its "Curie Temperature," its magnetism vanishes entirely. When the magnet cools down again, all the microscopic magnetic domains will point in circles, so the magnet will have zero overall field. Neodymium magnets have a low Curie Temp., so they are more sensitive to overheating than other types of magnet.

If we expose a magnet to the field from a strong electromagnet, the electromagnet will magnetize the magnet perhaps in a different polarity. But if we instead use an AC electromagnet, then move it away from the magnet, the magnet's polarity will flip back and forth, becoming weaker and weaker. The magnet will end up demagnetized. This is called "Degaussing."

Steel magnets are sensitive to mechanical shocks, and you can weaken a steel magnet by striking it with a hammer. Other magnetic materials are far less sensitive to hammering.

We can also demagnetize a magnet by forcing its poles together. For example, if we bend a horseshoe magnet so it forms a complete circle, its field will become a circle entirely inside the magnet, and it will have no poles or attraction. Or, if we grind a magnet up into small pieces, the pieces will align so the north pole of one fragment will be against the south pole of another, and the outside field will be small or zero.

* Submerge it in water
* Hammer it
* Rub it against another magnet
* Heat it

Answer - Submerging your magnet would only succeed in getting it wet! Magnetic fields travel just fine through water. However, if you hammer your magent or rub it against another magnet, youíll knock the domains out of alignment. If you heat a magnet past whatís called its Curie Point, youíll get the atoms so jittery that they wonít be able to stay nice and aligned. Itís like giving them a couple of Cokes

found here http://www.magnet.fsu.edu/education/...es.html#answer
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Old May 20, 2010, 03:41 AM
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Ok since that dead horse has been sufficiently kicked.

After you get yourself a heatsink for your motor, or maybe even at the same time. Get a pinion that is a few teeth smaller than what you are using now. This will drop your temp a bit. Castle Creations recommends 10t with an 8000kv motor.

Unfortunately it is hard to find a gear that is not made from aluminum that is that small. Aluminum gears really stink when it comes to the set screw. If you do use one, make sure to use some blue loc-tite thread locker and make sure to give it time to dry. Try not to overtighten cause the aluminum is so soft that it will strip the threads. Associated makes some 12t gears that are steel. I love those gears, they last a long time. whatever the case try to get steel pinions as small as you can.
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Old May 20, 2010, 07:54 AM
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Quote:
Originally Posted by urapoontaufa View Post
It causes the expoxy to melt off the windings and then causes the motor to short out. All sorts of magnets survive just fine in high temps.
how true
if every motor that simply got hot simply stopped running because their magnets became demagnatized so easily people would be killing electric motors left and right.
but being as that's not the case, and the overwhelming majority of electric motors die as a result of the windings shorting out and burning up, you are quite right!!!!!
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Old May 20, 2010, 08:49 AM
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All of the above are correct... Heat will short out the wires, "can demagnetize" the motor and can debond the adhesive causing failure... The temps are running too high.. Lower the pinion or change to a larger spur gear or both...
Your goal should be around 130-140's on the motor.. the esc is a little warm but not too bad.. your battery is fine..

Cat sammich.. nobody on this site is perfect.. leave the kid alone.. I haven't seen one post from you that has been positive in any way.. You keep referring to post trolling.. Look in the mirror.. 234 posts in 20 days and you've been on vacation for a part of that.. Why don't you take another vacation and think about that for a while.. Or the Mods will do it for you again...........
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Old May 20, 2010, 09:07 AM
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Cat sammich.. nobody on this site is perfect.. leave the kid alone.. I haven't seen one post from you that has been positive in any way.. You keep referring to post trolling.. Look in the mirror.. 234 posts in 20 days and you've been on vacation for a part of that.. Why don't you take another vacation and think about that for a while.. Or the Mods will do it for you again...........
cenracer1 -- instead of sticking up for the kid, and thereby promoting his trolling behavior (he's already chased off another new guy), or defending him because he's a kid - which all that does is make him return rejuvenated - how about suggesting that he slow down and not insist on posting a reply to EVERY-FREAKING-THING?

all the kid does is repeat things he thinks he's read elsewhere, and the majority of it is misinterpreted info, and then he goes around correcting people and he's flat WRONG. just like in the nitro fuel discussion on another thread, the guy was trying to educate him and yet he just had to post, being a smartazz coming back with snappy answers about a topic it was painfully evident he was clueless about.

because at the end of the day if people aren't able to get reputable advice, or the adults get hassled by punk kids still wet behind the ears, they'll leave and while it's just a guess it's my opinion why this place is so dead to begin with and while it'll die off like so many other forums where the adults get tired of the trolling kids just here to amuse themselves.
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