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3D Scanning a Locomotive Answered

I know nothing about 3D scanning so hope to find suggestions here. I have a large object I wish to scan and import into Rhino 3D and eventually cut (1:120 scale) on my tabletop CNC mill. The diesel locomotive upper nose has compound curves in its shape.

The red rectangles in the illustration mark the area of the locomotive that is difficult to reproduce accurately in a drawing. It is this area I would like to scan.

Is there a scanning system somewhere in instructables that is capable of scanning this large area of the diesel locomotive? If so, please point me to it.

Thanks much.


Downunder35, an exciting offer, thank you much!

I'm leaving town until the AM, so I'll be out of touch for 24 hours. A quick question, though: Will a Canon PowerShot SX10 IS (10 mega pixels, 20x zoom, optical image stabilizer) do the job? I don't know much about cameras. I do have a tripod.

Just now emailed the small museum that owns the diesel, asking permission to rig a photo shoot. I think I'll have to absorb the photo requirements you listed and probably ask a couple of follow up questions before I travel to the locomotive.

Please send me an estimate of your fee: grangerroads at imonmail.com

Only Electro-Motive Division (EMD) manufacturer blueprints would do for drawings, and I haven't been able to find any yet. The shape of the nose, that is its accuracy in model form, is a matter of great discussion (and criticism) among adult practitioners of the hobby. Precision is paramount.

Checked diesels in Sketchup and Thingverse, nothing there is accurate (thanks for the pointer, though, caitlinsdad). Downunder35, I viewed the MS diesel model of the above unit and my eye spotted inaccuracies, although it makes a fine impression overall. I am going to search for your scanning instructable, Downunder35, thank you for mentioning it.

And Kiteman, I'll search for the 123 Catch app and see what it's about. Thank you for that pointer.

The photo of the diesel in my original message is on display just 52 miles from my home, so if I knew how to map that section of the nose. . . .

Not sure, really, how to proceed. caitlinsdad, you say stitching together scan photos causes difficulties. Do I have any chance of accomplishing my goal, 3D mapping in some way the nose of this diesel?

Much appreciate all the help.

As I have done quite a few complicated scans in the past I could offer you some help.
If you can provide enough detailed images of the locomotive in question and send them to me I could make a 3D model for you.
In case you really only want the front section and not the entire locomotive the minimum requirements for a good scan:
Cam with proper focus (and tripod prefered) and 0 or more megapixel resolution.
One set of images from about 50cm height in 5 -10 degree intervals, so for a 180° view of the front about 36 images.
The same number of images at about 2 - 2.5m height and still horizontal.
Again 36 pics from that height but slightly facing down in an angle.
Last but not least 36 images from a height that covers the top and sides at the same time.
Additionally images of complicated or finely detailed areas.
Having accurate GPS coordinates in the EXIF data would make the alignment easier, same for the masking but it is not a must.
Once I got the images please allow about 2 weeks for processesing.

The 123 Catch app can turn a bunch of photos of an object into a 3d model - all you need is a chance to climb around a loco with a mobile phone.

I have an Instructable about scanning small things on a rotating platform, but the same applies for the big scale.
If you only need the front part with reasonable accuracy a series of 120 to 160 pictures in three different panes will get a good result.
For abvoius reasons it yould be best to have one pane at an elevated height so you can capture the top as well.

Any diesel locomotives already modeled in sketchup or thingiverse repositories? They would be more accurate made from scale plans. The 3D modeling based on photos of real objects loses a lot when you have to clean the stitched files together. Autodesk has something in their 123D lineup of software.