Re: NPC Motors

[Joe Sommer <anvilus9-at-adelphia.net>]

Kurt,

At 08:36 PM 9/13/2004 -0700, you wrote:
>what are your thoughts on the Robot Market place 24v motor/build your own 
>gear box offering under the NPC motors portion of their site???

That is a very good price for a motor,
a pair of spur gears, shaft, bearing and
wheel.

See if they will sell it without the wheel.

Based on the dynamometer data for the
NPC-02446 motors at
http://www.robotcombat.com/store_npcmotors.html#2446
it looks a little weak as discussed below.

You would probably need at least
one more speed reduction stage
to boost torque for a tank.

>  Is this price, with the wheel used as a drive for the tracks, in line 
> with the costs of gearing a EV Warrior

EV Warriors cost about $25 but you need 4
sprockets/pulleys, chain/belts, and bearings
for 9:1 speed reduction.  I estimate about
$100 per motor.

>how is cost compared to your gear and does it have more torque rating than 
>your drill motors???

It is about the same price ($150) as a 24VDC Makita drill motor
($96 motor/gearhead) plus two miter gears ($22+$32).
http://www.anvilus.com/Hetzer_components.xls

Makita 24VDC motors are rated 460 rpm
and 476 in-lbf.  Using the 4:1 gear ratio
with this kit, the NPC-02446 motor will
produce 506 rpm and 90 in-lbf.

>      Just some thoughts that came to mind after you switched to 24v, 
> combined with the speed/weight "bot" suitability they claim for the 
> combination....

Remember that "bots" do not need to do
full-kid turns with tracks in tall grass.
They play on smooth level surfaces.

>I can't wait to hear/see about Coxsakie...

It was a blast.  Vern Dernberger was there
in person and will file his report soon.  Also,
the cable TV Outdoor Channel had two
cameramen there filming for "Inside R/C".

Joe


**********************************************
Joe Sommer
2378 Nantucket Circle, State College, PA 16803
814.234.4773     anvilus9-at-adelphia.net
http://www.anvilus.com