Re: Chama Steam engine placement

The use of mid-train helpers on Cumbres was a result of when the third engine was cut in ahead of the caboose, it tended to buckle the wooden idler flats placed between the pipe gons. All the the cars were wooden at the time. The idlers were made from cut down high side gons with the draft gear below the car sills. The earliest idler conversions did not have any rail reinforcement to the car and they buckled easily. The answer to this was to put the loaded cars (tanks, boxes, etc.) on the head end behind the helper and the road engine with the mid-train helper behind them. To the rear would be the empty pipe gons and idlers. If the train was all empties, the helper would be placed about 1/2 way back to keep the slack tight with the helper and avoid the chance of buckling. With the later addition of steel flats (cut down SG cars)and idlers made from box and stock cars (which have the draft gear built into the center sills and with the addition of rail reinforcement made a much stouter car) eliminated the need for cutting the helpers in mid train. This is why most the mid-train shots are in the early 1950's with all wood consists and most of the post 1956 shots have some steel cars with newer idlers and the helper on the rear.
Any MOW cars were placed behind the helper - mid train or rear. On Craft's train we disguised two outfit cars as boxcars and we put the helper on the rear. The outfit cars have draft gear with no buff (compression) springing. The couplers were mashed into the end block on the cars. That's why I never did that trick again.