Skip to main content

Reply to "TMCC GP9 conversion - AC Pullmor to DC can w/ERR Cruise Commander"

Almost all the china drive trucks with 3xx Mabuchi motors are between 10 and 11 to 1.   Atlas made some with 15:1 this may have been only on 3 axle trucks. I don't have first hand experience with Atlas 15:1 gearing the reason I summise this is two years ago I ordered an idle gear for an Atlas FM Erie Built and they asked me if it had 10:1 or 15:1 gearing.   Lionel scale size Hudsons (700e, 773, 785 etc) are 18:1. Lionel horizontal motor F3  2333, 43, 53 are 9:1. Lionel 18000 B6 switcher is around 14:1 though it's easy to swap the upper gearbox from 2:1 to 3:1 and acheve 21:1. 90% of the Williams brass steamers are either 21:1 or 42:1 depending on whether the worm gear is a double or single helix. I have counted the turns on ten or eleven MTH premium steamers and they were all 18:1 the RailKing line is not so predictable. The AMT F7 diesels with the 7 pole Pittman universal AC/DC motors are 8.5:1. These are great motors and can be mounted in Lionel's vertical pullmor motored F3s and GP7s trucks with a little effort. They actually work better in the Lionel trucks than in the AMT trucks and will run much slower than the 3 pole pullmor.  The vertical motored Lionel diesels F3 & GP7s with diecast trucks are 8.5:1. Divide the wheel circumference by the gear ratio to get distance traveled per motor revolution.  Something I have been harping about is the change from 5xx mabuchi motors in early TMCC china drive Diesels to the 3xx series motor this almost forces you to have two powered units "4" motors to do the job that a single diesel with two 5xx series would do.   MTH started out with the 3xx motors in their diesels no one will convince me this was not aimed at selling you a second powered unit. Yeah I know the 5xx series motors will not fit in the narrow hood of a GP or SD loco.  Lionel followed their lead.  If either had gone to 15:1 gearing when changing to the 3xx motors  it would have negated the need for a second powered unit for most of us most of the time. Not to mention the improved slow speed performance.        j

Last edited by JohnActon

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
×