the ev's are pretty good in that sense the batts and ESC is the weak point there
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Mechanical engineers build weapons, civil engineers build targets

I found the Mini EV's have crap brushess like 99% of the cheap closed-can motors. They were kinda hit and miss... We killed a few of them fairly easy, and others (Like the pair in VL) have lasted quite a while.

Definately more confident with replaceable brush motors like the dewalt & astro flights.
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https://www.halfdonethings.com/

Simple question:
Does the current flowing through a fet affect its turn on/off time?

Simple answer - yes.

How much ? I dont know.
In our application (low switching rates <20Khz), probably not very much, but I havent seen a characterisation of the effect anywhere yet.

In low PWM rate motor, low voltage, high current controllers, The effects are probably swamped by thermal characteristics from the sustained high current flows. You could ask on the OSMC mailing list.. There are a few real mosfet guru's on there.

Mosfet switching is reminiscient of the pneumatic guys discussing designs for high flow valves for Co2. It seems like it should be simple, but its not.

Diverting large flows of any sort of energy suddenly always seems to involve far more factors than you would have even thought existed. Switch lots of current fast enough, and you suddenly have a radio transmitter (maxwells equations) and capacitances, self inductance and so on start popping up all over the place and screwing things up.

in summary. High dI/dt = Big Trouble.

A reference for you start at
http://www.smps.com/Knowledge/MOSFET_Switching/FETsw_p3.xml
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

I think its called miller charge.
I have seen it on the scope with loads as small as a few amps.
The gate drive was less than optimal though so it was probably exacerbated.
It made the gate ringing much worse than it was with no load
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Mechanical engineers build weapons, civil engineers build targets

Heres another good app note that covers temp effects and miller charge
http://www.audiodesignline.com/howto/showArticle.jhtml?articleId=196602897&pgno=2
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Does anyone happen to know how many turns there are on a typical 12V drill motor? I am looking for a higher voltage replacement and the high turn "lathe motors" at Tower hobbies might be an option: http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXLYV2&P=ML I figure a good starting point for 24V operation is a motor with double the turns and half the wire gauge of a 12V motor - any suggestions?
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

i believe that its about 18-24 i cant rember exactly.
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Mechanical engineers build weapons, civil engineers build targets

I wish I had kept a toasted motor now! It sounds like a 45 turn motor is a good place to start. If it means an end to rate limiting and melty motors, then $18 USD will be worth it.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXKUG5&P=C

55T Lathe Motor - US$18.59

If you decide to order some of those motors Nick, let me know. I might be interested in a set for something.
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https://www.halfdonethings.com/

ditto to that, if any r ordered iol grab two to play wioth, may work good for next orbit as motors that copme with banebots setups r only rated to like 14 volts or something
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Andrew Welch, Team Unconventional Robotics

If we bought six or more, the discount would probably pay for the postage and the exchange rate is the best for years .

One thing that worries me is that we don't know what the wire gauge is - if it was reduced too much, the winding resistance would go up and power output would go down. There was a 24V motor listed in the Mabuchi catalogue like that - 24V but a crappy power output.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Meh, with A123's, just up the volts
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https://www.halfdonethings.com/

take a look into the rc rock crawlers, i was interested in getting one a while ago and 99% of them run the 550 size lathe motors. and im sure they run fairly high voltage.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

@ Glen: Interesting, that would mean they have to produce a reasonable amount of power - I'm in! I bet they use the high-turn motors to reduce the need for expensive multistage gearing.

@ Aaron: I am already using Lipo packs; higher voltage just means more weight at this point.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion