Old-time Four Bay Hopper Project
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I dubbed this car "the car that refuses to be built". This car is a 70-ton quadruple hopper built by the standard steel car corporation in the late 20's. The car had a capacity of 140,000 pounds at 2,739 cubic foot level with the top. The length was 42'-6" over the striker faces. All my information came from the Train Shed Cyclopedia No.48. The book has line drawings of the top, side and end views plus several cross-sectional views. There are also a couple of black and white photos.

This car had several features that caught my eye and made it look like an interesting project. I have already built 8 of the Gill Rittenberg hoppers and basically just copied what he had done. I did redesign the center beam for more strength by using thicker material and welding it rather than riviting it together.

I wanted to take his car a step further with a design that I had not seen in the inch and a half world. Starting from scratch and using my new skills at AutoCAD seem to be a better way to go than the old method of full-scale drawings on my board. Eventually that proved not to be the case.

The problem seemed to be that the drawing was easy to make but after the material was cut and bent there was nothing to compare it to to see if looked like it would fit. It is hard to tell with sheet metal if the angles are correct or just look correct. The material I used caused some problems also. I used what is called 18-gauge paint lock steel that is .045 thick. The advantage is that it has a zinc coating that holds paint, doesn't rust and is very clean to work with. You can tell from the gray of the metal in the photos.

The disadvantage is that it can't be mig welded very well. These particular bunches of steel sheets were very tough. It was almost like working with stainless. It was difficult to form into a sharp radius and couldn't be unbent once bent. Basically there was no fudge factor.

I think in years past the same material must have came from a different supplier. This material in 20-gauge would have been great. Also, just plain cold rolled or hot rolled steel would work very well.

Getting to the car and its characteristics. The car has stepped sides rather than slanted sides at the end. This made for an unusual 5-point bend to offset the sheet .400 of an inch. Normally one would assume that the sheet would have to be cut and welded to make this shape. Being the great metalworker that I am. (joke), I was able to figure out a way to stretch the metal into the needed shape in one piece. That figured out, I thought I was well on my way to building the rest of the car with no problem. Wrong.

Next came the special sidepieces at the ends that stick out like stretcher-bearers. They have an odd shape and also have the .400 offsets to match the upper side. For that I made 3 dies. Two to form the left and right versions and one to form an offset for the lower side angle that goes the length of the bottom of the car.

Next I built a rather large plywood table to mount into the milling machine vise to hold the side sheets. I used the CNC machine to drill all the holes. The mill was only able to drill half of the sheet at a time making it necessary to flip the part. With careful alignment, the two hole patterns lined up very good.

After most of the interior sub assemblies were made and assembly was started, I discovered things were not going right. The problem with AutoCAD is that it is difficult to work with untrue length lines or to say lines that do not lie flat on paper. Dealing with two or three of these lines meeting on a computer screen in the same place is just plain tough. Of course, you can print these computer drawing out full size but I don't happen to have a 36" plotter with a 100' roll of paper on it in my den…

I guess the jist of this discussion is - with this project I learned that computers are great but sometimes one still has to rely on old fashion pencil technology.

More dies were made and more are coming to finish this project. Hopefully at the end of nine months of labor my shop will give birth to a new car. Check back from time to time to see what the little bast^%* looks like. LOL.

Continue to Hopper Car Construction Part 2 -->