Hi Les,
3D printing really is very much in the future of the hobby, in any case. It won't replace injection moulding anytime soon, but it might just threaten some resin casting in a short while. In addition to eliminating most of our resin kit range and resurrecting some of them in 3D, I myself have ceased scratchbuilding and doing any production work by hand. I'll still build kits for myself, and I'd like to build my dream layout someday, but for many personal projects, I find myself CAD-drawing whatever parts I need and then printing them, whereas before I might be sculpting them out of Evergreen plastic or something else. I'm actually pleased to be done with that.
Problem with depreciation of a 3D printer taking a few years is that the technology is moving so fast and getting better all the time, that your machine will be obsolete long before that. It's like computer and cell phone technology. I really wouldn't recommend buying your own 3D printer right now unless you intend to get into 3D printing itself in a big way. Otherwise, it's best to just use the online services and let them worry about all of the unpleasant stuff. It will allow you to make more stuff for yourself!
Injection moulding and 3D printing are for different purposes. It is still more cost-effective to do a production run in plastic than any other process, chiefly for the reasons you cite (though I might dispute the perception of the costs and prices for railroad models, but that's for another conversation). 3D printing is not for large production runs right now. Small parts, perhaps, but not things like body shells. 3D parts take too long to print and the cost for a typical HO one-piece body shell is between $100 and $400 (depending on the length) in the best process (less any profit you might have to make on it). N scale is a bit cheaper for 3D printing, but I find it's easier to sell N scale bodies and parts directly from a site like Shapeways and forgo the ordering for inventory and tracking of orders, particularly for one-off or limited-interest items. There's a question of the 3D resin material's long-term stability too, but it seems to be fine for most everyday static modeling.
You can use cutting edge technology in your personal modelmaking and still get a tremendous sense of accomplishment. I think Kurt is doing that right now with these bilevel cars. If it were me, I would have done the whole car in 3D, but he found a way to do it within his budget and is using the sides with some available cars and parts to help speed it up and keep things consistent with other models. Kurt decided there was a better way than cutting and sculpting pieces of Evergreen sheet plastic himself. (Obviously, you valued your sanity, Kurt!
) We don't have to cede everything to RTR or new technology, nor do we have to give up modeling even in hard times, and there is such tremendous diversity of offering to us to fit all budgets. I personally am not worried about any of that. I've seen some nice models made from cardboard and there are even some nice ranges of models made from cardstock that have big followings. That's what is great about this hobby and I think it will largely continue to be so.
Kurt, are those bilevel cars smooth-sided or are there some ribs or corrugations? If you plan to add anything to the sides with liquid cement, remember to brace the sides somehow from the inside. It will help prevent warping over time. Also, if you're doing laser cutting for the sides, did you consider having the windows laser cut to fit? It's extra work to install each window, but how cool would it look!
Mike Bartel
IHP
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