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Old 06-19-2003, 10:09 AM   #1
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Default Dry Ice.

Does anyone have any experience with dry ice.

Ever used it to keep motor cool during the race?
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Old 06-19-2003, 10:31 AM   #2
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I've tried it, but there really isn't any perfomance advantage, except on a very hot day. The cooler the motor runs, the more efficient the power usage. Some people use compressed air (the kind you use to blow off dust on your keyboard), turn it upside down and shoot it into the motor. Just be careful not to spray the commutator, or the bushings/bearings.
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Old 06-19-2003, 11:06 AM   #3
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I live in Greece and it gets very very hot!

Our major problem, even with 12 t is overheating the comm, brushes, and just about anything!

Please describe how you used it.
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Old 06-19-2003, 11:44 AM   #4
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Simple, place a small piece of the ice directly on top of the motor attached to the car. Leave it on there until the ice evaporates, then run your car. You will see that you should maintain better power throughout the battery pack. I use to leave the ice on there until it evaporates or the start of the race.
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Old 06-19-2003, 11:40 PM   #5
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Default dry ice

If you cool the motor down too much, wouldnt the magnets crack when the motor heats up due to rapid temperature changes?
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Old 06-20-2003, 12:23 AM   #6
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heat does not build up instantaneously in the motor... therefore there is no sudden temp change...
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Old 06-20-2003, 12:27 AM   #7
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Default .

wouldnt it have some affect throughout a race?

its the same as when you put a hot cup in the freezer or a cold cup in a dishwasher .. they expand and contract quicker than usual causing them to crack ..
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Old 06-20-2003, 12:29 AM   #8
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well, this technique has been used by many pple and so far i have never heard of magnets cracking...

i guess maybe the temp change is not as abrupt as putting a hot cup in the freezer or a cold cup in a dishwasher...
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Old 06-20-2003, 12:31 AM   #9
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Default dry ice

Alright then,

i might give it a go .. just didnt want to fuck up a new motor :P
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Old 06-20-2003, 01:38 AM   #10
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isnt the idea behind using ice, not to keep the motor cool but to keep the components cool so that they dont get to hot and break or come un soldered... its considered better to finish then to not finish at all because of a broken spring or joint that has come un-done
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Old 06-20-2003, 02:33 AM   #11
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Motors work more efficiently when they are between a certain temperature range. If they are to hot they become inneficient and when they are to cold they are also not as good.

You notice when you have overgeared a motor it becomes slugish towards the end of the run.

All the ice does is allow the motor to finish cooler then it would normally finish after 5 minutes.

Tony
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Old 06-20-2003, 06:31 AM   #12
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i use spray freezer on motors,batts,speedos because the cooler they are the more effecian they get.they will not cause the magnets to crack because the motors all at the same temp[typiclly -50oc before race and at about +60oc after using stock were as other poeple i race who dont freeze it there motors come off at about 150oc!so the advantages are longer run time more power,higher effciancy.disadvantages is if you freese brush wires they could become brittle and brake and if you freeze the motor bearing they could seize if they do just roll the car a full time and then rev the motor a bit to warm the bearings
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Old 06-20-2003, 08:57 AM   #13
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I've never heard of freezing the components, it gets about 100F out here in the summertime, and although I try to stay at the indoor tracks, parking lot racing is closer to home. I have seen some of the janitors at work with the freeze spray stuff, I'll see if he'll hook me up with a bottle for some testing
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Old 06-20-2003, 01:25 PM   #14
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Hey Neil,
Should I spill the beans on the dyno-tested, trackside proven secret of getting away from the pack and getting 2-3 blazing laps before the motor settles in, basically it's a holeshot in the bottle okay more of holeshot in the can. On a dyno it has been tested to improve a motor's RPM/Torque to about 10%. I know you know, because you've seen Rod do this.

Hint: It can be found at all major office supply stores
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Old 06-20-2003, 01:53 PM   #15
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It works well with stock motors and mabuchi's. If you need to do this to a low turn motor in order to make it fast, then you've got other issues to work on hehe
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