(ET) Re: wheel brakes

[Dan Conine <dconine dotnet com>]

I recommend you find something a little more flexible than welding the 
spiders, unless you are in an emergency situation. They will eventually 
destroy themselves this way. Seen it before.

As far as individual brakes: From years of experience with tractors in 
fields, the individual brakes do only one thing well: stop that wheel from 
moving. That means, it stops or slows your pulling tractor, also.

You want energy going in the OTHER direction. 

A limited slip or locked differential is really the way to go, but do it 
so that you can depend on it. Find a local machine shop to make bolt-in 
blocks or a 'spool' that will lock the gears, rather than welding the 
teeth. You need some kind of 'give' to your lock, because the gears are 
pretty brittle, and axles aren't perfectly aligned under loads.

The guy with the roller chain idea had the right idea, but you should come up with the ratio that you want, and eliminate the gearbox altogether, possibly using two motors and electrical differential which can put power to the wheels individually. Roller chain is more efficient than gears are, and easier to repair. You could also put the motor at a strategic location to balance the CG this way, also. 

JI Case used a roller chain drive on tractors up to 100 HP through many 
decades.

Dan C.
E-15
E-10




"Pieter Litchfield" <plitch@attglobal   To 
            .net>                     "Elec-Trak Tractor"                 
            Sent by:                  <elec-trak cosmos phy tufts edu>    
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            @cosmos.phy.tufts                                             
            .edu                                                  Subject 
                                      (ET) Tractor Pulls                  
                                                                          
            03/25/2004 08:03                                              
            AM                                                            
                                                                          
                                                              
> Here's a tip based on some hill climbing and racing experience.  If you are
> thinking about dedicating a tractor to pulling, open up the rear end and
> weld the differential spider in place.  You now have a solid rear axle and
> two wheels driving rather than one.

> If there is a rule against this or you want to preserve the differential
> for lawn work, it might be possible to mount a brake drum on each rear
> wheel and at least be able to transfer power manually from the spinning
> wheel by applting the brake to it.

> Just a thought.....