SD70 Heritage Units

[jward]

here are a couple more, from that 37A which ran yesterday. unfortunately, the Wabash/southern combo headed south out of Harrisburg, so I never got to see them. But what I did catch was even more spectacular.

Epic power consist on 37A, passing two SD80MACs on a 591 empty coal train. 37A had the redbird, a regular NS sd70ace, the UP Olympic unit, a CP ac4400, and a UP sd60.





closeup of the redbird.





the Union Pacific Olympic unit.

[jward]

htc trucks have an offset center axle? are you sure? the whole purpose of the redesignedtruck used under the dash 2s and later units was to get the traction motors all mounted in the same direction. thus the bracket on the inboard end of the trucks, next to the fuel tank. there should be no need for an offset axle.

offset axles were used by builders other than emd, to provide room for a reverse mounted traction motor. the widened spacing between axles allowed two motors to fit between the axles.

all sd70 type locomotives use a radial designed descendent of the htc truck, in which the axles actually pivot in the truck frame around curves. this has reduced wheel and rail wear, and allowed these units to negotiate sharper curves than similar sized locomotives with traditional trucks. 

[ALCO0001]

htc trucks have an offset center axle? are you sure? the whole purpose of the redesignedtruck used under the dash 2s and later units was to get the traction motors all mounted in the same direction. thus the bracket on the inboard end of the trucks, next to the fuel tank. there should be no need for an offset axle.

offset axles were used by builders other than emd, to provide room for a reverse mounted traction motor. the widened spacing between axles allowed two motors to fit between the axles.

all sd70 type locomotives use a radial designed descendent of the htc truck, in which the axles actually pivot in the truck frame around curves. this has reduced wheel and rail wear, and allowed these units to negotiate sharper curves than similar sized locomotives with traditional trucks. 

Sure thing the radial trucks are an off shoot of the hi ad truck evolution so there is a slight off set of the center axle,the Bachmann 70 series is not using a  radial truck axle spread totally wrong ,they basically cheaped out and used the spectrum dash 8/sd45 truck they already had,they have the 40-2 truck but it is well not as well made and has the tower mount thing  that pops wheelies under load if you lucky to get one that is a little unstrieght in the axle bearing,BUT THE TRUCKS ARE SOME OF THE BEST MADE 3 AXLE IN THE MARKET I THINK!