RE: Transmission Help [TANKS]

["Bruce Robere" <mi21stinf-at-wideopenwest.com>]

Tanks much Joe outstanding help as always.

Bruce

-----Original Message-----
From: tanks-admin-at-rctankcombat.com [mailto:tanks-admin-at-rctankcombat.com] On
Behalf Of Joe Sommer
Sent: Wednesday, March 02, 2005 6:43 PM
To: tanks-at-rctankcombat.com
Subject: Re: Transmission Help [TANKS]


At 04:58 PM 3/2/2005 -0500, "Bruce Robere" <mi21stinf-at-wideopenwest.com>
wrote:
>I'm powering my tank with two 24v DeWalt motors/transmissions.  In gear one
>they produce 450 RPM and 2000 RPM in gear two. I assume this is no load
>RPM????

correct

>My track system is #2060 attachment chain.
>If I use a 60X15 sprocket (per T017) and set the DeWalt transmission to the
>450 RPM gear I should be able to use the same size pulley for the
>motor/transmission shaft and the sprocket shaft.

correct

The 24V DeWalt DW006K-2 drill produces 550 in-lbf
http://www.dewalt.com/us/products/tool_detail.asp?productID=4089

The 24V DeWalt at RobotMarketplace is also rated at 550 in-lbf
http://www.robotcombat.com/marketplace_dewalt.html

A 1:1 pulley ratio should provide plenty of torque.

>This should produce about 4.5 MPH, I think...

correct

One revolution of a 15T #60 sprocket will advance
the chain 11.25 inches (15 x 0.75 inch pitch).

450 revolutions will advance the chain
5062.5 inches = 421.9 feet = 0.0799 miles

0.0799 miles per minute = 4.794 miles per hour

You will probably get about 4 mph under load with 15T sprockets.

You could use 17T sprockets to get a little more speed
because the DeWalts provide so much torque.

>Second, what's a good source for v-belt pulleys with 1/2 inch diameter
>shafts that are keyed? I checked the local Grainger's and on-line with
>McMaster-Carr but all their 1/2 inch diameter shaft pulleys are keyless.

If you cannot find 1/2 inch bore pulleys with key ways,
check if your local machine shop has a broaching machine.
It is pretty quick and cheap to cut standard 1/8 inch key
ways in pulleys.

Joe


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