3 D printing

Also check out the Tinkercad website.  Great, free way to make lots of O scale models yourself.

I also like and use Tinkercad.  I have downloaded HO 3D models and scaled them up 2x with the slicer that came with my 3D printer.  That gives me access to many model train items to 3D print.  Items can also be scaled with Tinkercad but I find it easier to do in with the slicer.

Programs for making print files? Or the files to be printed? Your question sounds like you're looking for a place that has files to be printed.

I like Slic3r for making the gcode files. I'm not picky on the CAD side. I have used a number of CAD program and it seems like most of them have a learning curve that stinks by now I have learned to complain as I go. Some programs are definitely better than others but I don't get too stressed because it's for fun. I have no time constraint.

Put a file into a slicing program and change the scale. Doesnt matter what it starts out as.

Is the final product expense?  Twelve of these benches were a dollar apiece including delivery.  If I made one on a 3D printer, what do you think it would cost?  It is about 1 1/4 wide.  Thank you, John

if in resin the cost is minimal to print; the real cost is the time it takes to create a model to print.

I used TinkerCad to make these bridge pier masters then printed them out. I'm going to make molds of yet, then cast in hydrocal but I think they turned out decent, pretty fun stuff!