Re: New Accurail Offset twin hopper


Dennis Storzek
 

Well, glad someone finally noticed we are releasing a twin hopper.

The prototype is basically the AAR standard car as illustrated in the 1940 Car Builder's Cyclopedia, although we actually used several P-S drawings from the Pullman Library of the Illinois Railway Museum for data. This car has a 33'-0" IL. One difference is the Z bar end posts as opposed to the pressed channel sections only below the slope sheet. The car does have the angled end sections on the side sills, as Ed Hawkins mentioned, same as our 70 ton triple hopper. In fact, the entire end of the car as far in as the bolsters is the same as the 70 ton car, because as Ed surmised, we are re-using the cavity inserts from the 70 ton car tooling. We are also using the same detail parts: brake equipment, rugged sill steps, slope sheet braces, and hopper doors that are used in that kit.

All this short / long taper stuff is getting confusing, because most offset cars have a taper from the bolster to the corner post, no matter how they look from the side. Ed worked out what I think is a better terminology in his article in RP Cyc No.1; AAR Standard, Alternate Standard, and non-standard offset twin hoppers. What we are doing follows the AAR standard design. The end panels taper from the bolster to the corner post, but the line where this taper meets the inward slope of the top of the side sheet terminates about 18" from the corner; because of this the top chord of the sides have a bend at that point, giving the car somewhat of a bowl shape in plan view. The Alt. Standard cars have a completely straight top chord, and therefore the line where the two angles meet runs all the way to the corner, and this line is not parallel to the slope sheet. These cars also use hat section stakes, so the rivet pattern differes from the AAR Standard car. I was willing to tool the new inserts to model the hat section stakes, until I realized that this always goes along with the "long" taper line on the end panel; since the budget was based on using the existing tooling parts, I abandoned that idea and did the standard car. What Ed calls "non-standard" cars typically have a double bend offset in the last panel, and again have a straight top chord, I think. I don't actually have any fabrication drawings for a car of this type, so haven't actually studied the geometry.

This is one problem with thinking that one can just change the end panels of the side to produce the different versions. When one actually looks at the situation in 3-D, one finds that the shape of that end panel also affects the shape of both the inside of the car and the area under the slope sheet, and necessitates re-doing a lot more of the tool than is at first evident. This is not a case where modular design is going to be effective. Maybe someone will tool one of these minor variations someday, but the lure of thirty-some roadnames on nearly identical cars is hard to resist. We'll leave those versions for companies that like to do $42 cars. Our kits will be one third that price.

The tooling is complete and we had test shots and a built up kit at the show in Milwaukee. At Accurail test shots are done to check cavity finish and venting issues, not to see if the geometry was correct so we can build it right the second time. The tool is presently back together and waiting it's turn after the parts for the new autorack with side panels to finish molding, and they should start showing up in the shops before Christmas.

Now to tool a coal load, since the load we do to fit Athearn cars is too wide.

Dennis Storzek
Accurail, Inc.

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