My son owns 2 of these 3-D printers, and from what I can determine, he places the object under his camera attached to the printer, and it either photographs or scans the item to be 3-D printed.  I'm not entire sure of the process, but he has been able to make me some amazing items using this technique.  He modeled, (in 'N' scale) the entire Vancouver, WA train depot from his 3-D printer, and it is an exact replica of the real thing.  All it needed was painting to look like the one down the tracks from our home.

I did.  They don't carry that specific part.  I am going to have to 3-D print that replacement part.

I am in need of two of the long steps, one for the front and one for the rear of my Bachman 2-6-6-2 Mallet. This is the long, horizontal stepping platform just above the couplers that the brakeman would step up onto after connecting or disconnecting cars from the front or rear of the engine.  In Bachman's exploded parts diagram for assembly, this part is listed as OAYO6, if anyone is able to see that.  Both of them came loose and fell off somewhere on my outdoor layout, and I have been unable to find them.  I suppose one could 3-D print replacements for these missing items, but I would need just one of them to use as a template.  If anyone has a spare one, (or two), I would be happy to purchase them from you and pay for shipping.  I am trying to get this engine ready for the upcoming National Garden Railway Convention in August, of which, I am a participant, as my layout will be on the tour.
Thank you everyone for reading this and responding if you can help me out.
Sincerely - Trainman700