Re: Motor's [TANKS]

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

Jim,

At 05:37 PM 12/11/2004 -0800, Jim Neifert <jneifert-at-shaw.ca> wrote:
>This is to Joe, or anyone for that matter. Joe you have stated (I think 
>anyway) that we need somewhere in the 400 in/lb range to make a full skid 
>turn. Just curious, but the DeWalt 1/2 hammer drill with gear box is 
>stated to produce 550 in/lb at 450 rpm. Would this not be a good 
>combination for our tanks?

The dread T-34 #T005 introduced EV Warriors
(EVWs) to our hobby.  At 9.17 to 1 reduction with
12V power, EVWs provide 241 rpm at no load
and 396 in.lbf stall torque.  The dread T-34 has
plenty of torque for full skid turns in tall grass.

Hetzer #T010 used 12V Makita drill motors
that provided 400 rpm at no load and 320
in.lbf stall torque.  It could do full skid turns
on pavement and in short grass, but could
not do full skid turns in tall grass.

Hetzer #T010 now uses 24V Makita drill
motors that provide 460 rpm at no load and
476 in.lbf stall torque.  It has plenty of torque
for full skid turns in tall grass.

Consequently, I estimated 400 in.lbf torque
for full skid turns.

550 in.lbf from the 24V DeWalt hammer drill
and gearbox at
http://www.robotcombat.com/marketplace_dewalt.html
would be great.

>Reason I am asking is, a shop that I was at was throwing out a 14.4 volt 
>cordless drill with gear box, the rpm at 16 volts is about 450rpm. I am 
>not sure about the torque but it is up there. I ran it on three 6 volt 
>gell cells and held pressure againest it for some time, it got warm but 
>not hot. My gloved hand got hotter than it did.

450 rpm would produce 5.36 mph at no load
with a 4 inch DIA sprocket.  However, I cannot
say anything about the torque unless you can
provide the manufacturer and model, or find motor
specs.

The old style 14.4V DeWalt motor and gearbox at
http://www.robotcombat.com/marketplace_dewalt.html
produces 600 rpm at no load and 290 in.lbf stall
torque when operated at 14.4 VDC.  I estimate that it
would produce 363 in.lbf if overvolted at 18V
(290*18/14.4).

The new style 14.4V DeWalt motor and gearbox at
http://www.robotcombat.com/marketplace_dewalt.html
produces 450 rpm at no load and 400 in.lbf stall
torque when operating at 14 V.  When overvolted
to 18 V, it produces 450 rpm at no load and 450 in.lbf
stall torque.

A new style 14.4V DeWalt operating at 18V would
be OK.  An old style 14.4 DeWalt operating at 18V
would be marginal.

Joe


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