micro_Amps
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I think Tiny RC bought it and it got merged, or something like that.
One of the American guys will know.
:)uAThey sure do.
:)uANot likely, the windings are copper and therefore not magnetic.
Some people have said that perhaps putting a magnet beside the motor will strengthen it, but the chances of getting the poles in the right place are 100 to 1. Also the steel casing of the motor will divert any external magnetism around the internals of the motor, instead of through it.I am reasonably sure that the magnets in these motors do weaken over time. I have a few 3.8s that have had some use, but not alot, and now a fresh 3.0 can leave them for dead.
:)uAYes, the clones (and other higher speed motors) have a finer wire in the ‘mesh’ that surrounds the core. (These motors are known as coreless motors because they dont have an armature that spins). The finer wire is needed to pack in more windings, which in turn, will produce a higher rpm but at lower torque.
The Tomy, and some slower motors, have thicker windings and because of this when the motor is powered off and let to roll, the Tomys will generate more back EMF (reverse voltage) and slow down quicker.
With the clone motors thinner windings dont create as much electrical resistance to spinning without the power on, so they will roll on for longer when you stop the power supply to them.
As far as ‘tightness’ all the motors use the same method of bushings, through the magnet at the front and a plastic casing on the back end.
The main achilles heel in this design is that is you run a motor hard, it heats up, and the heat on the shaft can melt the end cap and distort the hole where the shaft cames through.
:)uAThat ‘crab’ is the symbol of “Realtek” the originators of that chip.
Although I think these days most of the Rxc/Txc chips are made under license by others.
:)uANot sure on that one, I havent taken any rpm readings with the different batteries.
:)uASo if I am correct it would be along the lines of…….
The gearing on the sample car was 12:1,
The rear wheel diameter (with average BCG tyres fitted) measured with vernier calipers is 13.84mm.
So if circumference is Pi x D (or 2 x Pi x r) then the circumference of the rear wheel is 13.84mm x 3.14 = 43.46mm
Now according to Panda….Quote:“rollout”…..is just the Inverse of the gear ratio X the circumference of your drive tyre.That means that our 13.84mm wheel rear axel with a gearing ratio of 12:1 would have a rollout of…
43.46mm (circumference) / 12 (gear ratio) = 3.62mm of travel per motor revolution.This makes perfect sense as a thicker or different tyre will change the rollout, and therefore the effective gearing.
Just to take this a little further.
If I have a microB 3.0 motor in that car, running at a perfect 30,000 rpm, what would the actual speed be?
Well if the car travels at 3.62mm per rev, and the motor is doing 30,000 rpm, then the car would be doing (3.62mm x 30,000) = 108600mm per minute. Or 108.6 meters per minute.
Times that by 60 to get meters per hour, 108.6 x 60 = 6516m/Hr or 6.516Km/h.
So a 12:1 geared car with average BCG tyres and a 3.0 motor should run at around 6.5km/h.And then to take it to extremes….
The same car, running a 4.2 motor, 3.43 bit racer gears, and the same tyres, would run at…
43.46mm / 3.43 = 12.67mm per rev.
12.67 x 42,000 = 532163mm per minute
or 532.2 meters per minute
times 60 = 31929.7 meters per hour or….
31.9Km/h !!!This is a theoretical maximum only, there are lots of ‘losses’ in the drive train, being friction, heat, noise, wind resistance, battery and motor production deviations, just to name a few.
I know from practical examples that using a triple cell car and the above setup, that this speed is possible, but the car is very difficult to control.
So there you go. Sorry for starting your Saturday with a maths lesson.blackeye:
:)uAAhh, you gotta love it, beautiful one day, kite flying weather the next.
:smiley2:uAI think I might know how the landings turn out though. :D:D:D.
Somehow, I dont think the occupants would survive.
:)uAThat would mean carrying the coil and the diodes on the car as well. More weight.
Could be done fairly easily though.
This is a good idea.
:)uAGot a couple of cyclones (hurricanes in your money) swirling around the top end too I see.
:)uAZb, the SBCG ‘High Speed Set’ has only got two gear sets.
The red 8.25:1,
The orange 9.86:1 is sold as standard with all the cars,
and the yellow 12:1But the set comes with front suspension, a 3.0 motor, and front knuckles as well.
So that makes the ratios on the SBCGs the same as the original BCGs, just different colours.
:)uAYes please.
:)uAYes, there is,
Blue 4.75:1,
Red 3.95:1,
Green 3.43:1
They used to sell them in sets for the Bit Racers, but you will be VERY lucky to find them anywhere now, trust me.
:DuANo signs of Avian flu though I hope. :smiley2:
Welcome to the friendliest micro rc board around Chook.
:)uAYep sure are.
What frequency is that one you have there?? :smiley2:
J/K, the shapes / facets are pretty amazing though.
:)uAHehe, WTF is that???
Front spoiler or snow plough.
Nice wing too BTW.
:)uAX mods are nteresting, cheaper build than a Z, but still tonnes of fun.
They are able to be fet modded in the same way as Zs, and take a 6 cell mod too. Easy to get 35kmh out of them, not too far away from stock.
They both have some shotcomings, but dont they all.
Both have loads of potential, but the Z is setup as a whole industry on its own with lots of hop-ups.
Will be modding them both to the max, eventually.
:)uASorry dude, got a mortgage to pay and a boss to placate with my presence.
:)uA
I used to know a girl that swore crystals had magical powers. She used to rub them under her furry armpits instead of deoderant.
She stank !!!!
So much for the magic.:)uA
Edited by – micro_Amps on 02 March 2004 23:21:33
You like the easy projects dont you Panda. :smiley2:
Bugger the cost, put me down for one. 😀
:)uA
How high can we go?
So I guess in Mini Z terminology, this is a 4 x 3 stack. :DuAYep, good on everybody for contributing.
Funny to think 12 months ago people were saying “Bits are dead”, well 25000 posts later, the proff is in the puddin.
Keep it going people. 😀
:)uASeems like this is turning into a threead on “what I’d rather spend my money on other than that RC magazine car”….
so I’ll add to it.Panda already knows this, but I (for some unknown reason) want to return to my childhood and restore a Sandscorcher.
But, alas, I cant afford another mortgage.
:)uABetty, I’ve pretty much got the SE steerin sussed now, I am doing steering fixes for people, just havent put it up on the website yet.
They go very well once the steering is fixed up, and have about 5 or 6 increments of steering in each direction.
Kinda getting off topic here.
:)uA -
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