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Old 11-08-2002, 02:50 AM   #16
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Quote:
Originally posted by Manuel
I've had magnets unglue themselves... i found that araldite holds up better
is "araldite" an adhesive? ive had a couple of motors with unglued magnets and i used CA but it only lasted a few runs before ungluing again. maybe a stronger adhesive is the solution. thanks for any info
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Old 11-08-2002, 04:23 AM   #17
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Araldite is a 2 part epoxy resin adhesive found in hardware stores throughout Australia. It may have a different name in the US but I am sure that there would be a similar product available. It comes in a double Syringe and when the two parts are mixed together it forms a high strength adhesive.
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Old 11-08-2002, 04:37 AM   #18
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Ye Araldite is a resin/hardener thing. Very smelly; but very sticky. I roughened up the inside of the can and then put the magnets in place... I tried superglue too, it was useless.

The front end of my rx7 body had fallen apart so much that i just decided to cut it off and go for that bumper-less look. Im sure it helped the motor, but it also would have contributed to drag (lift?) quite considerably. Another of my bodies which has had its bumper opening meshed makes negligible difference... not that i notice anyway
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Old 11-08-2002, 08:13 AM   #19
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Quote:
Originally posted by Steevo
What motor are you running and what spur/Pinion are you running? That will give us something to work on.
I have a pretty puny, wimpy sissy little motor (if you havent heard of it, that is the name) I run it in my Tl-01 so it doesnt get much air. I run it with a 19t pinion, and the speed tuned gear kit. (very small track ) If it helps any I use a futaba mc330cr esc.

Thanks
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Old 11-08-2002, 11:12 AM   #20
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a friend and me gear our motors so they dont go over 150*
it has worked really great so far! motors last a lot longer, oh and never use a heat sink! traps way to much heat in the motor!
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Old 11-08-2002, 02:20 PM   #21
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Quote:
Originally posted by Northerner
a friend and me gear our motors so they dont go over 150*
it has worked really great so far! motors last a lot longer, oh and never use a heat sink! traps way to much heat in the motor!
Sorry but i just have to ask, How does a heat sink "trap way too much heat in the motor"??? That goes against any logic that i subscribe to.

Last edited by Steevo; 11-08-2002 at 02:22 PM.
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Old 11-08-2002, 03:28 PM   #22
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Because most heat sinks don't make good physical contact to the actual motor can. In effect just trapping the hot air in the vents by cutting off air flow. If you use some contact paste to help transfer the heat from the can to the sink it helps.

If you have good contact and heat transfer, then use it... If not it is better to just leave it off.
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Old 11-08-2002, 04:11 PM   #23
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who said anything about logic. He started off by saying "a friend and me"
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Old 11-08-2002, 07:33 PM   #24
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thanks for the replies i dont think this is available where im from, but ill try to look for an equivalent. ive seen different kinds of 2-part epoxy and ill probably look for the high-temperature type.
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Old 11-09-2002, 12:10 AM   #25
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Quote:
Originally posted by ChristopherKee
Because most heat sinks don't make good physical contact to the actual motor can. In effect just trapping the hot air in the vents by cutting off air flow. If you use some contact paste to help transfer the heat from the can to the sink it helps.

If you have good contact and heat transfer, then use it... If not it is better to just leave it off.
I understand what you are saying and it makes total sense, I have never really thought that hard about it before.
But if thats the case, then companies who are manufacturing these heat sinks are misleading people and are being fraudulent. If one sells a product for a particular purpose and it does not do what it is claimed to do then that is misleading. I personally have never been told when buying a heatsink, to buy some contact paste nor is any supplied therefore one would assume that it is not needed. I am sure that many would share the same opinion. I would have also thought that the heatsinks would have been manufactured so that they fit the motor can snugly and effectively dissipate the heat otherwise what good are they??
Its great that all these pretty colored alloy bits and pieces are available to us but wouldn't it be great if they actually made a difference instead of just looking good???

Anyway thats just my 2 cents worth.
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Old 11-09-2002, 12:17 AM   #26
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Quote:
Originally posted by popsracer
Has anyone tried cutting out a "Grill " opening in the front of the car to let more air in. Not a hole in the windshield like a nitro car.
Just a small 1/4" to 3/8" slot somewhere above the bumper to let in a little more air.
This isn't a suggestion, It's a question.
I have cut the grille out on my Skyline GTR body and fitted light wire fly screen to the inside with hot glue. It looks real nice but I am not confident about the cooling effect as the motor is at the rear and probably sees little of the air.
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Old 11-09-2002, 12:51 AM   #27
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this is the case with the yokomo mr-4 pro. the bottom heatsink is just about useless.
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Old 11-09-2002, 04:02 AM   #28
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There is one other basic problem with measuring the temperature of the motor on the outside of the can, The hottest part of the motor is the armature... It does all the work... So the can temperature just gives you an idea of how hot the armature is... and it's not very acurate...

If you get ten of the same engines, run them in the same car with the same gearing, and the same ambient temperature, you will get ten very different temperature readings...

Also, with heat sinks, there is no point putting a heatsink on it it will not mak good contact with the can... Also, low airflow areas are pointless for heatsinks.

The best heatsink's I've seen are where they are incorporated into the engine mount... However the must not block ANY air vents on your motor can... This can be really bad, as most motors like to 'breathe'... That is to say, the armature, as it spins, creates a cooling airflow around the can...
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Old 11-09-2002, 05:42 AM   #29
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Quote:
Originally posted by Shadow_Rusty

Also, with heat sinks, there is no point putting a heatsink on it it will not mak good contact with the can... Also, low airflow areas are pointless for heatsinks.
I agree with most of what you say except for the above quote about "low airflow areas are pointless for heatsinks".
When the heatsink is making good contact and not blocking any cooling holes (as it does in the motor plate style heatsink)it does help dissipate the heat away from the motor. If heatsinks do nothing in low airflow areas then why do they bother using them on audio amplifiers and other electronic equipment which are usually in areas which have little airflow. Most early computer CPUs were fitted with aluminium heatsinks without fans mounted on them and you could hardly call the inside of a computer case a high airflow area.
Heatsinks are used widely in the electronics industry in one way or another so they must have some merit or the companies wouldn't waste their time fitting them.
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Old 11-09-2002, 05:52 AM   #30
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Yeah, I agree, however, when you compare the size difference between say an audio transistor and it's heatsink (Usually about 15 times the size of the transistor) to that of an electric motor and it's heatsink (Usually about 1/2 the size of the motor), that is where airflow is a must. Hence the reason for cpu fans...

In general there is at least a little bit of airflow... but not enough to cool a heatsink. Most heatsinks tend to increase the 'cool' period of the motor.

We had the modified nationals here recently, and of all the car's I saw, I don't recal one of them using a clip on heatsink. Just the ones that were incorporated into the engine mount.
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