All, In a search for odd Mallets This popped up 4-4-6-2 - Wikipedia this photo of a 2- 4- 6- 0 did as well. Tom
Yeah, the two 4-4-6-2 types were spectacularly unsuccessful. You could run a compound steamer at very high speeds if the high and low pressure cylinders were right next to each other. Run a long dry pipe between them and the back pressure within it would pretty well prevent any speed over 30 mph, even with 73" drivers. Once the extra four drivers and big reheater were surgically removed, however, each became a nice Pacific. The GN had 2-6-8-0 types too. The smaller radial chassis was considered logical because it carried less weight, so fewer drivers and smaller cylinders were theoretically needed. But fewer drivers meant less traction, so these forward drivers were even more likely to slip, smaller cylinders or no. That's why they didn't catch on.
The GN 2-6-8-0 of the M-2 class were fairly successful locos on the GN and lasted until almost the end of steam on the GN. Southern Railway also rostered some.
B&O also experimented with some odd Mallet types. They're mentioned in "B&O Power" which, sadly, my copy is not in easy access at this time. There was a 4-4-6-2 when they tried, I think, to swap a 2-6-0 front engine with a 4-4-0 type (MK-1, M-class 4-4-0, with some large drivers; B&O had several classes of 4-4-0 based on either wheel diameter or cylinder size, IIRC; and K for the 2-6-0 (in reverse) rear engine. I think they tried a few more but none of them seemed to have the success that true Mallets like the 2-6-6-2, 2-8-8-0 and 0-8-8-0 fleets. Some were simpled, or each set of cylinders receiving fresh steam (no compounding) and the "Yellowstones" or 2-8-8-4 war babies were all simple. Shame that none of these were preserved but at least we have a good selection of photos.
