Well, my project is complete and it is time to post the log. I will be doing this over several days as it contains 90 pictures. First the disclaimer. Although the project is based on a prototype railroad piece of equipment the model is not intended to be a scale copy. It is only intended to be a representation. With that said here is my project. This is the inspiration. I took this photo in Chama, NM in 2005 thinking that at some time it might make a neat model. I also took about 50 pictures at the same time. The model is based on those pictures, pictures from the Quick Pic book by Rick Blanchard and scale drawings from A Century + Ten of Narrow Gauge Cars by Robert Sloan.
For those of you who don’t recognize it, it is Derrick OP of the D&RGW. Originally built in the Alamosa shops in 1911, it was built with a wooden boom. In 1921 with the coming of newer and heavier rolling stock it was rebuilt with a steel boom and had the car body strengthened. Derrick OP had no boiler, its winches were powered by steam from the locomotive. In practice the tender car would be left on a siding and the derrick pushed to the work site. The derrick has two winches which control the boom lift and the main hook. The swing was controlled by block and tackle, operated manually or with a gypsy drum on the winches. In normal use the derrick was tied to the rails for support but if swung more than a few degrees of centre then outriggers and blocking were necessary. The main boom had a swing range of about 25 degrees each way. It also had tie down rings on the rear where it could be secured to a locomotive of heavy car in order to increase its lifting capacity. Derrick OP is stored in Chama NM and is in operating condition although not in use. In the beginning there was this, a 1x6 spruce board.
After an hour or so at the table saw we had this pile of scale sized stripwood
Which began to assemble into this. The frame of the tender car
Here we see the decking being applied to the frame. The decking is all individual planks. I find that building the basic frame this way results in a straight and true structure to build on.
Here is a shot of the decking applied after it comes out of the jig
This is the underside of the derrick car with the decking already attached
Here is a shot of the derrick car with the needle beams installed and one of the truck mount
Here are a couple of shots of the underside of the derrick car, the brake cylinder is salvaged from the frame of a Bachmann flat car kit.
And here is the underside of the tender car
That is all for today.
