RC Mower

Introductions, general chit chat and off-topic banter.
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Adverse Effects
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Post by Adverse Effects » Thu, 19 Jan 2017, 22:32

yes the motors you linked to are "geared" reduction
easy to turn the motor from the output shaft relative to the gearing reduction
to get a 100 to 1 reduction would need several gear steps
Image

the one i linked to is worm drive reduction
very hard to turn the motor from the out put shaft due to the inherent drag and massive reduction of the worm drive

to get a 100 to 1 reduction is easy to do with a worm and a 100 tooth cog
Image

this is why i was trying to get you to get 90deg worm drives :-)

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EV2Go
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Post by EV2Go » Fri, 20 Jan 2017, 02:17

Ok I see how the worm drive works now.

I don't think I will need anywhere near 100:1 reduction.

If I did the math right a 300mm (12") diameter tyre only needs 150rpm to do 8.44kph

Most of the motors I was looking at were around 3000-3200rpm ungeared.

3000 / 150 equals a 20:1 gear reduction.

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Adverse Effects
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Post by Adverse Effects » Fri, 20 Jan 2017, 06:50

EV2Go wrote: I don't think I will need anywhere near 100:1 reduction.

no no no no lol i wasnt saying you need 100:1

i was just saying its easy to get with a worm drive

the worm drives i have on mine do bit slower than walking speed on 12VDC and a slow jogg on 24VDC and a quick jogg on 36VDC (but 36VDC is a bit to high for my controller lol burnt one out trying it)

so with most brushed DC motors you can play a bit with the speed by changing the voltage but you do lose some power as you drop voltage down

like mine on 12V i can stand in front of it and it just pushes hard on me but on 24V it will ether spin the wheels or push me over

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EV2Go
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Post by EV2Go » Fri, 20 Jan 2017, 23:45

Seem to be a few sites around selling 8" Wheels and 10" Wheels

Voltage: 24V
Power: 350W
No Load Speed: 213 RPM
Loaded Speed: 181 RPM
Output Torque: 18.3Nm
Reduction Ratio: 16.5:1
Splined Shaft
Brushed Motor

So 181rpm x 250mm diameter = 8.66kph

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