Thoughts on On30 vs Sn42…

DDT Sn42 CritterSince discovering there were actual 30″ prototype railroads in North America I’ve been dabbling in On30 and I just got my first On30 locomotive, a Bachmann 0-4-0 Porter. For the price (less than $80 including shipping) it’s an amazing detail – nice detailing, runs very smooth (at least on DC – haven’t tested the built-in DCC yet), and best of all it matches almost perfectly the drawing I have of Eureka Mill Railroad #1. Setting it next to my Model Power DDT diesel – a locomotive that’s often mentioned as a great “On30″ critter – is instructive, and got me thinking about Sn42 again. In real life Porters were truly dinky locomotives, but sitting next the the DDT it actually looks large in comparison. In other words, the DDT is much too small for O Scale but seems perfectly sized for S Scale (when I put it next to my Sn3 locomotives it’s sized similarly and it’s noticeably larger than my Sn2 Forney). But I decided to measure…

The On30 Porter measures 2-3/16 tall at the cab, scaling to 8’9″. The Sn2 Forney measures 1-13/16, scaling to 9’9”. The difference in scale size seems about right (it should, I know they are both accurately scaled models), so the Porter should work OK as a “2 foot” porter if the wider gauge doesn’t bother you.

The DDT diesel critter scales to 8’6″ in O Scale – even shorter than the dinky Porter. In S, it scales to 11’4″, exactly the same as my P-B-L SP ten wheeler (#8) and slightly taller than my Tyco old tome 4-6-0 and my Sn3 C-16. The confirm it’s too small for O Scale (unless you’re modelling a really tiny locomotive) but just right for S Scale.