RSC3 trucks

[sirenwerks]

I have been staring at this photos for a while and trying to figure out - do the trucks have the same axle spacing as the RSC2 but an exterior design more like the RSD4/5?

[Curtis Kyger]

A quick internet search found this unit listed as an RS3C; which tends to confirm equal spacing between the wheels as seen in the photograph. Not RSD spacing.

[sirenwerks]

A quick internet search found this unit listed as an RS3C; which tends to confirm equal spacing between the wheels as seen in the photograph. Not RSD spacing.

Thanks.  I didn't realize that was what the "C" and "D" designation meant.  Now onto the second half of the query - is the truck design different - the Atlas RSD4/5 design on a Kato RSD2 spacing?

[PGE_Modeller]

You have hit the nail on the head with your question. Yes, the RSC-3 truck is a modification of the RSD-4/5 truck. Or, possibly the other way around depending which came first. The RSC-3 truck had a wheelbase of 11'-0" with equal spaces (5'-6") between the axles while the RSD-4/5 had a wheelbase of 12'-6" with axle spacing of 5'-7" and 6'-11".  The ALCo drawing of the RSC-3 truck is dated Feb 18, 1950 so it may pre-date the introduction of the RSD-4.  To the best of my knowledge, the Seaboard and Pacific Great Eastern were the only railways to order the RSC-3.  If you have access to Carsten's Publications "Loco 1 - The Diesel" (1966), there is a drawing showing the RSC-3 style on page 87.

Cheers,

[nkalanaga]

The big difference is that the RSC only had two traction motors per truck.  With no motor on the center axle, there was room for it to be in the center.  The RSD truck had three motors, so the center axle had to be off-center, as the center motor had to share space with one of the other two.

[sirenwerks]

To the best of my knowledge, the Seaboard and Pacific Great Eastern were the only railways to order the RSC-3.

The Soo Line had 4 units.  They ditched the three axle trucks eventually and retrofitted them to standard RS3.  IIRC, the PGE did the same to some, if not all, of its units too.  The SAL was the only one to keep the three axle trucks .  The RSC3 should up around the world, in S America, Cuba, Pakistan, and Algeria.  That's where I spied the RSC3 a few weeks ago, the Algerian units; I was researching North African rail history, getting ready for a trip to Morocco (unfortunately, no train travel will be had while there).