Trinity 5160 AOK

[Robbman]

They're not exactly identical, but they are all based on the centre-flow design concept that ACF originally pioneered, except that these Trinity and Greenbrier cars both have heavy center sills. ARI also builds through-sill cars, but the ACF/ARI center-flow (and other copies of it) has no center sill but used the heavier side sills to support the car. The old Canadian cylindrical hoppers also used this sort of design.

The differences between the Greenbrier and Trinity car are there, and reasonable obvious when you know what to look for.
Bolsters/jacking pads: Square (with rounded corners) on the Trinity car, more trapezoidal on the Greenbrier
Side sills: Straight across the entire length on the Trinity, only between the bolsters on the Greenbrier
Sides: Trinity is slightly more curved, the Greenbrier, while still curved, is slightly flatter
Roof: different eaves and roofwalk supports.

Being a little nit-pick-alicious here... but the ACF Center-Flow design was the no center sill design with the car structure providing support... so a car that has a through sill design really can't be said to be based an it.  Pullman-Standard pioneered the through sill center outlet design... just not on cars with a cylindrical body... as an aside, P-S also had a center-sill less design (the 4785 variant of the 4427 is the most common).

Gary, certain design features are inherently not patentable, like a cylindrical body (if Apple made freight cars that might be a different story), and many appliances (doors, roofwalks, hatches, grabs, cut-levers, outlet gates, etc) on freight cars are made by outside manufacturers anyway (ACF, Stanray, Morton, Apex, Equipco, A.O. Smith, etc).  Many manufacturers do have patents on some features, for example Johnstown Americas cylindrical tub design was patented... but only for a straight tub, Trinity got around this by having a slight downward cant to the tubs for a while, until the ten years on the patent were up, Thrall just ignored it, and was taken to court by JAC*)...


*Complete and total aside here... but the NS at one time had a semi-cylindrical tub design (2 actually, basically half an octagon with round edges) for the TopGons,  but because of JACs patent and ongoing litigation with Thrall (who supplied a set of cylindrical tubs for one TopGon), it was decided not to implement it.  They instead went to Trinity and had the exisiting tub design stamped, and thus, the smooth tubs cars.

[GaryHinshaw]

Thanks Chris and Robbman.  The nub of my question was the extent to which a given feature was considered patentable.  I guess that is more or less always in play.  To follow up on Chris' point, here is a pair of shots for comparing details:

Greenbriar (same shot Robb posted)
Trinity

The side sill and end cage details are obviously different.  I would love to have both models available because mixing them in a train subtly pushes the realism IMHO:

http://www.railpictures.net/viewphoto.php?id=338991&nseq=35
http://www.railpictures.net/viewphoto.php?id=385414&nseq=13

(but I understand that is not very practical).  The recent BLMA TopGon announcement is a nice example of this approach though.  In any case, I'm getting my order in - along with some of Prairie Shadow's other special runs.

Thanks,
-gfh

[Robbman]

Thanks Chris and Robbman.  The nub of my question was the extent to which a given feature was considered patentable.

From what I've seen... depends on the uniqueness as to how a part was made or the feature itself.  I.e, FCAs one piece cold rolled center sill (vs taking two standard Z or C channels and welding them together)... Trinitys Rapid Discharge Longitudinal (RDL) unloading bays, etc.

Another aside... the RDL isn't really new... Trinity acquired the idea when they got P-S

[GaryHinshaw]

My order of these special run hoppers arrived today and they're really nice!  I also picked up a few of the other special run hoppers that Prairie Shadows has commissioned, which include some interesting paint outs.  I also secured several more BNSF hoppers for my grain train (these were already sold out in a number of shops) and some ExactRail TTX railgons.  Jeff @ PS was great to deal with, and I didn't have to worry about customs.

Happy days.