Could a forum member please give me the approx. dimensions ( L,W,H ) for the SD40 model. The rest of my motive power is by AZL, I was wondering if they are compatable. regards, John.
What do you mean by compatable? They use different motors and run at different speeds. I'm sure others have had success but I haven't been able to lash up azl and micro trains engines together. I'm not using dcc. I really like the sd40. I don't have any dimensions right now but it's very nicely done.
When I was querying the compatability it was the SD40 physical dimensions as I understood that MTL models are slightly overscale, so might look out of proportion to the AZL locos. John.
John, welcome to the group. The AZL GPs match the prototype dimensions better than the MTL GPs, so that running the two together will look a bit strange to the skilled model railroader, but my SD40 looks reasonable with the AZL GPs. I haven't done detailed measurements on the SD40 yet, but in general, the newer the model, the more prototypically correct the dimensions. There was an article in a recent Ztrack magazine with some "then vs. now" examples. Steamfan does bring up an interesting issue with Z locos: the trend toward matching the speed performance to the prototype. The SD40 max speed is 55MPH and the GPs 65MPH and like real life, the GPs will outrun the SD40 at maximum DC throttle. This can create problems if you don't run the GPs ahead of the SD40. Mechanically, the SD40 should run on layouts with >+145mm curves. The unit uses body mount couplers and the center wheels are flangeless which allows them to run well on the tighter curves. Hope this helps, Mark
Many thanks for all the help. As regards the curves I have 195mm and 220mm so should be ok. regards, John Skegness, England.
Welcome to Trainboard John. The SD40 will look fine with the AZL SD70's. The longer dimensions of the SD40 spreads the width better. I think the speed of the SD70 and SD40 its very close. I run them is consist, but I run dcc. If you run 195mm curve, put a body mounted car next to the engine to avoid derailments.
the hood width on the SD40-2 is not bad. As shamoo737 says with the long hood it looks alright. Not anything like the GP35 and GP9. As for running them together. They have slightly different ranges. Mine run faster at most voltages then my AZL. I would let the MTL engine lead as it tends to try to push the slower AZL engines and their truck mounted couplers try to steer off the track.