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Penciled out, it would be a significant increase in cost to do a modular system, especially with the Heavyweights. I had this all planned out to be modular before we ever started, but once the math was done, and the number of parts you would have to inventory and track were listed, the plan sorta went south. Just looking at the roofs gave me a headache! Remember, each part touched is extra US$$ Assembly is an issue and an additonal cost...consider cutting and assembly fixtures, some or all specifically designed for a single part use. I can see someting like this working for light weight passenger cars because so much is common and more floor plans were shared among different railroads. Still, look at the cost of the Centralia (sp) cars even assembled in China. Those bad boys range from $40-$50 each...Great concept and I see the application for a whole host of car body styles...just need to figure out a way to make assemblying 8 parts together as cost sensitive as 4.CheersJoe
Roofs are the same headache either way, so I'm not sure why they are being used as an arguement against a modular system? Base roof and adding different ac venting and details was considered here. This would have to be a glue fixture and the mess would be un-godlyEverything else could be exactly the same as what you have now with one exception: A "core" with ends/floor as a multi-tool piece with sides that snap in as simple A-B molds.As it is, folks are concerned about how tight the roof to side seam is...try doing that with all these extra parts. we can hold tolerance, but the fact that you are trying to get 4-5 pieces all lined up and maintain the high expectations would be difficult...not impossible, but what's the cost to pull that off...fixtures, pretty advanced digital skills by assembly etc. All it takes is one part 2k out of tolerance or distorted while cooling could through the whole thing offSo, what MTL does now is one piece part, complicated multi-slide mold for each carbody. (If you simply cut new side inserts for changing from 12-1 to 10-1-2, for example, let me know.) new side slides is the best method here, but we had to do some runs and check the marking on the core from the window shutoffs striking that surface. If we got any sort of distortion, you are looking at a lot of flash through a window opening that may span that indent. As it has proven, we are not seeing that denting of the insert thankfully. We had to go through the exercise to be sure we could consider new side slides on a car like this.What Bryan says would be cheaper, and I would tend to agree, would be a single Core to cover all the full length Pullman's ends/floor. Then simple A-B (two part) molds for car sides. I think this works on something like full size head end cars...looking at those now. You have to promise not to get upset when you see seams on the ends of the cars at the spot the sides connect with the ends. )Pros: No banana boat problems or lost time trying to solve complicated tooling issues. New car styles after the first one are cheaper to do (A-B versus multi-slide mold). Painting and decoration of flat car sides would potentially be much easier, fewer holding fixtures for pad printing. You still need to add in the extra roofs...not too many go from one floor plan to another and if they do, it may be a proto that may not sell. As for ease...kind of a wash really, the unitized bodies flip on the paint and print fixtures and can be held in place with a quick clamp. seperate sides need to be pre cut off their sprue's and then painted and then held down someway on the print or mask machines. Suction only works on small parts...clamps mar the paint surface and how do you protect the finished sides when you press them onto the core. This must be friction fit requiring some sort of mechanical press. We can't cut after the work is done because those surfaces would be exposed and ugly!Cons: Extra assembly step, main body is now 3 piece instead of 1 piece.TrueAll other parts could be exactly the same as what you're doing now. Do the cons really outweigh the pros? I'd be interested in some actual numbers there, but I know what USA A-B tooling for car sides costs, and can't imagine how the extra labor cost would outweight those savings (over standard quantities for this industry). Tooling costs would diminish once the first set was done, but the cost to set up higher...man hours, resource allocations, one set up for the unitized shell vs two for the modular unit...one for the core and one for the sides. These cannot be done in the same mold as you know...so double the mold set up, testing and pre-production time.
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