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Tamiya mini cooper

Old 03-04-2011, 09:26 PM
  #14611  
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The difference in resistance,of thicker wire, with wire lengths used in a M03 (say) will be negligible . Unmeasurable with a normal multimeter.
no-one is using a 4T motor in their mini ??

Stranded wire dissipating heat better than solid wire, really ?? are you just making this up as you go.

Now lets start talking about induction effects, & skin resistance due to the switching frequency of the esc.


Last edited by 1101; 03-04-2011 at 09:37 PM.
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Old 03-04-2011, 09:37 PM
  #14612  
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Nah. Just stick some 16ga silicone noodle wire in there and drive the wheels off the sonuvabitch!
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Old 03-04-2011, 10:50 PM
  #14613  
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Grandpa, you are an old Scheisser Anfanger! You've found yourself a whole new source of chuckles here... I'll check back later to see if one of these guys can actually answer your question.

Sir Swifty, Unlap yourself, catch the bus, and come get your butt wupped tomorrow...because Grandpa gave me a new old back from when he was still interested in 'em screamer...I call it the Brandonater
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Old 03-04-2011, 11:27 PM
  #14614  
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Originally Posted by SirSwiftAlot
HOLY JESUS !!! Someone please start a thread on wiring resistance to horsepower loss and heat index control PLEASE. This is absurd. How about this!!!! Run the damn wires that came with the speed control. Or better yet run consistently enough to tell the difference between 18 gauge and 10 gauge and I will personally fly to where you live and buy you a cocktail and a lapdance for your intense research and results. Grandpa you damn shit starter Ok anyone looking to sell a KO controller?
Just stirrin the pot a little Swifty. Some of that stuff was way over my head cause the last physics class I took was over 55 years ago. Appreciated the responses and learned a little bit. I had to rewire one of my Minis and used a smaller gauge wire than the surplus telephone cable I usually use.

By the way. which of the two holes in the 1.5 rear upright do you use to mount the camber link. I use the upper one, but was wondering if using the lower hole was better. Changing from one to the other does alter the suspension geometry somewhat.
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Old 03-05-2011, 12:17 AM
  #14615  
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Every time some bull$hit squabling goes on in the mini thread, there is always a common denominator. I'll let you guys work out who i'm referring to

Unless your consistency number is .10 every race ( and I mean consistently fast , not slow ) , the difference would not be noticeable.

So go for the aesthetics Granpa, there's no point being fast if you can't look good at the same time
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Old 03-05-2011, 12:50 AM
  #14616  
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Originally Posted by Granpa
By the way. which of the two holes in the 1.5 rear upright do you use to mount the camber link. I use the upper one, but was wondering if using the lower hole was better. Changing from one to the other does alter the suspension geometry somewhat.
by dropping to the lower hole it will lower the roll center.

depending on how much grip your track has to offer will determine which hole to choose.
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Old 03-05-2011, 04:50 AM
  #14617  
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I wrote an article about wiring sizes, resistance and electrical efficiency for RCCA about, oh, 1997 or so. I can't post it here because they now own the copyright, but I bet someone could find it out on the Interwebs somewhere...
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Old 03-05-2011, 06:56 AM
  #14618  
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Originally Posted by I)arkness
by dropping to the lower hole it will lower the roll center.

depending on how much grip your track has to offer will determine which hole to choose.
So would the lower roll center provide more or less grip?
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Old 03-05-2011, 07:08 AM
  #14619  
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....
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Old 03-05-2011, 08:01 AM
  #14620  
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Default Camber gain/roll center

Upper hole = same as plastic parts = more camber gain as suspension moves, and works best (for me) with M03. Lower hole = obviously less camber gain, and works best (for me again) with M05. At least at Tamiya track using Spec tires...
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Old 03-05-2011, 01:08 PM
  #14621  
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Hi All,

Quick questions on TRF shocks (54000) on the M-05:

1) Should I use the urethane bushing on the diaphragm? What effect does it have?
2) Should I use the o-ring spacer on the shaft?

Thanks as always
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Old 03-06-2011, 03:34 AM
  #14622  
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Originally Posted by niznai
If you ever measured a toaster and or a bulb you would notice they have a very low resistance (actually, a 100W bulb rated at 240V would have to have about 0.4 Ohm resistance. That's very low by any standard).
Current = Watts / Volts = 100W / 240V = 0.417 Amps.
Resistance = Volts / Current = 240V / 0.417A = 576 Ohms.

You forgot to turn the light bulb on; both figuratively and literally.

Originally Posted by niznai
You really need to get your science right man, but start with the facts first, if you want to keep any semblance of credibility.
We finally agree.
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Old 03-06-2011, 03:37 AM
  #14623  
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Originally Posted by superspeed
nice minis

lots of blue parts on the m05
Thanks. And I'm convinced some of the blue bits are bling only, very dubious about the performance enhancement potential of some! And I can't image the chrome plastic is the most durable. Hearing some of the screws go in, even greased, was difficult.
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Old 03-06-2011, 04:20 AM
  #14624  
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Originally Posted by djmcnz
Current = Watts / Volts = 100W / 240V = 0.417 Amps.
Resistance = Volts / Current = 240V / 0.417A = 576 Ohms.

You forgot to turn the light bulb on; both figuratively and literally.



We finally agree.

You're right, my mistake.

Still, that doesn't mean a higher resistor will heat more at the same voltage.
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Old 03-06-2011, 05:43 AM
  #14625  
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Default wire guage

How many amps do you think a silver can pulls in a mini, and for how long. By far the most power is used from a standing stop on a high grip surface. If you are already moving the amperage is much less, and on a lower grip surface, the tires just spin. I have used 16 ga novak or tq wire in mini's and they don't heat up or cause much resistance (resistance is heat, hence a resistor.) If we were talking about low wind brushless motors on a touring car, 13 or 14ga wire is better suited, but in a mini it really doesn't make a difference.

As for connectors, just use a deans plug and be done with it. Less failure, more secure, and last much longer.

Let's get back to mini's.

p.s.: if v=ra and v is the voltage drop, if we keep v the same and increase r, then a is decreased, in other words, it takes less current over a higher ohm resistor to drop the same number of volts.

The table below is the resistance per foot of typical guage wire: (in r/c we rarely use more than 6")

12 0.001588
13 0.002003
14 0.002525
15 0.00318
16 0.00402
17 0.00506
18 0.00639
19 0.00805
20 0.01015

The voltage drop of 12 guage wire over 6" and conducting 20 amps is: .01588v and 16 guage is: .0402v. Now you might think this is significant (it isn't), but in a mini, a lot of extra power is simply transferred into wheel spin. We also assumed 20 amps continuous, which would mean a runtime of 12 minutes for a 4000mah battery. Since mini's can easily run 20 or 30 minutes with a 4000mah pack, the average draw is about 10 amps, which means a resistance of .02v in a 7.4v battery. Do you really think that makes a difference?

Last edited by billjacobs; 03-06-2011 at 05:59 AM.
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