I calling this “Step 1” .. most of the parts arranged where they will go so I can get a look at it.
I need to add on the other ‘bits’ seen in the drawing .. squarish blocks, rectangular boxes etc. I’ve found that it works better if you build your mesh slowly .. cleaning it up as you go. If you add to much at once time you can run into problems with too many intersections – just take my word on that.
At this point the model is still full size. The next step will be to make a copy and re-size that to scale. I am doing one for Ralph in HO and one for myself in O scale.
I leave details to after scaling since this is a VERY SMALL model in HO and you will quickly start to run into the 3D printing constraints. This collection of primitives will easily scale down. The cylinders themselves are small .. In HO the one sticking up (3″ dia output nozzle) will be only 0.035″ dia. That is well within the minimums. The only issue the flange thickness in HO. At 3/4″ .. it scales to 0.22mm .. which is below the minimum of 0.3mm for wall thickness. That will be thickened to that .3mm .. which will scale back up to 1″.
So here is where we leave this for a while. You can gaze fondly at the body primitive while I go to Step 2.