Just look for a brief history of the various diesels Lionel made in the MPC and LTI era. Essentially how did the GP and SD frame change. And when did the diecast frame of the BNSF Dash-9 from 1999 originate? Was the SD frame always diecast or did it start off as a modified stamped metal GP frame?
Replies sorted oldest to newest
I do know that the first issues of the SD frame where sheet metal and then around the mid ninetys thaty became die-cast to make them better pullers, then with the arrival of the traction tire, they went back to sheet metal and it was cheaper for them...
Marty
Mike - The first SD locos in 1978 (Mil Rd Limited Set and Santa Fe) used basically a GP frame with a shorter fuel tank to accomodate the 6 wheel trucks. The first SDs are the same length as a GP-7, GP-9 etc.
It's worth mentioning that the first iteration of the can-motor SD trucks, as found on the Milwaukee road set from 1987, had a traction problem. If I remember correctly, the wheels with the traction tires did not make full contact with the rails, giving the engines very little pulling power. The problem was corrected on later models. I did a chassis swap on mine, which now has the chassis from a later model with a Pullmor and Magne-traction.
I think the first SD model that shared the same frame and body shell (except for the low nose hood) as the GP7/9s were identified as SD18s by Lionel and later the variant SD24.
I used to have the Santa Fe dummy version of the SD18 (6-8873) long ago before I got into more scale and accurate trains, and I remember being struck by the fact that the handrails, while still stamped steel, was more visually appealing because it was ran all the way up to and ended at the cab front and back instead of abruptly ending just before reaching the cab and a simple metal wire was used to simulate the handrails leading up to the cab as was the standard on the GP7/9s from the postwar period onwards. I believe that engine was released in 1979 or thereabouts, so it would be right in the Fundemensions period.
Mike - coilcouplers.com has some info as to changes in the TMCC GPs
http://www.coilcouplers.com/hirail/tmchist.html
John - The Santa Fe 8872/8873 SD-18s were a late 1978 release, along with the non matching black and red bay window caboose that collectors didnt like.
As has been said, the lower-numbered SD series engines (SD-9, etc.) are really just Geeps with 6 axles. Therefore, they had the same frame: stamped steel with the edges turned down. The SD-40s were different: they were roughly scale sized, and had a full-width shell (That is, the side and front walkways are part of the shell, not part of that frame, as on the Geeps). Under this wide shell was a flat steel frame--no turned-down edges. (With the shell removed, the flat frame flexes under the weight of the motors and fuel tank; with the shell on, it is plenty stiff). The early 90s Dash-8s were built on the same frame: only the shell was different. I don't have a Dash-9, so I can't comment on those.
John - The Santa Fe 8872/8873 SD-18s were a late 1978 release, along with the non matching black and red bay window caboose that collectors didnt like.
Yes, was interesting that Lionel sometimes used to tailor production to meet collectors' demands. Because of those demands, they stopped making the no. 9274 red/black roof Santa Fe bay window (which incidentally is a nice looking caboose -have one) and started making the non-prototypical blue and yellow version no. 9317 to match those engines.
Access to this requires an OGR Forum Supporting Membership
