I have my DM&IR 2-8-8-4 handy and the Arbour 2-6-6-6 handy,
I JUST laid down a 2nd loop on my test module shelves, this having 30 inch radius and 28 inch using flex track, using ribbon rail roadbed curve pieces to find the curves. Laying down the track on sunday took about 2 hours work. Initial tests after laying track showed abherrations in track laying and various module mating problems. I honed down problems today, sticking legs underneath to lift the modules levelish. Not perfect. The 2-8-8-4 was drerailing at one spot along with other cars, bad track alignment on the curve, fixed.
So after some problem solving I finally try out the big guys on the track. Most of the track is layed down very close to the track design for the modules but for the short bit to make the loop.
No pics, but here ya go.
I have 23 cars as a train with varying types, the SJV caboose with the LED marker light showing up nicely, I put the 2-8-8-4 on it. It makes it around but in areas the drivers are slipping, but does get around the loop.
So I put the 2-6-6-6 on. I chugs around, but finds a spot to die on the track, bad pickups, time to fix that with 2 wheel pickup on each driver set, that needs improving somehow. But the engine makes it around and apparently no driver slippage.
Score 1 for the 2-6-6-6 arbour.
I tried my Little Joe South SHore on the train, it pulls it, but hits the same problem curve and shorts or cant pull it, bad track area, I know it. pfft. I noticed contacts were loose that I installed, so gotta redo it and recheck it over.
Put the DD40 on the train, all round pulls it, no probs.
Put Atlas FP7 on it, pulls it around, but some slippage, close to the 2-8-8-4, but surprised this unit drug the train around.
Ok, well, since the Yellowstone couldnt pull that good (I will weight it later) I decided to doublehead the Allegheney and Yellowstone, 2-8-8-4 in front as the "Gheney had couplers front and back.
I start the train for a short then suddenly the Yellowstone pulled forward suddenly leaving the 'Gheny behind. I backed everything up but things were shorting, grrr...
I looked at the front of the 'Gheny, wheres its front coupler?
I lifted the Yellowstone off, oops, its under it. Criminally, it pulled it out of the 'Gheny! Well, the Kadee coupler was clipped and screwed down onto the 'Gheny pilot, not your standard Kadee, but the narrow shank with center coiled spring inside. It was mounted just for the looks....shank was clipped so it was an easy pullout for the powerfull yellowstone...
oh well, back to the repair house..