Modern Rail Viaduct Project - elevated single track - updated 9/12/24

Rustoleum textured spray paints will go well with this project.  Try a couple of them and see which one you like best.  For modern concrete try their Desert Bisque.  Go easy -- don't let it run.  You can always add on a light top coat later.

And be advised they take awhile to dry! Don’t touch to test! Don’t ask how I know. I used some to simulate ballast on a bridge module.

Well thought out and Nicely Done Alan!

I think you are well on your way to making an exponential leap in TinkerCad.    I did it backwards... I started out using 360 and then TinkerCad ...silly me!

Dennis

I started with TinkerCad, a solids modeler.

Until I went with Rhino 8. a surface modeler

Thanks for the feedback!

Your suggestions for a more "concrete" looking finish are well received, PLA filament does look very plastic.   Using a texture spray paint like Rustoleum Desert Bisque would work very well.  However there are a few other things I will to try first.  

For experienced 3D printers the using the "fuzzy" and "seam" printing options are well known - but it was new to me.

So I tried it on a few pieces and to me itʻs an improvement,.  In the first photo, the original is on the left, and on the right shows the "fuzzy" and "random seam" settings.

The next photo shows the sleeve I printed with the texture that slips over the existing column, rather than re-printing the entire column.  The "sleeve" printed upright without any problem and slipped over with a snug fit.  It also widens the column for a more fitted look.

This photo shows a test placement of the O72 curve using the 9" tall supports.

I will be designing guard rails to keep derailments from falling off the upper level, something low profile using the same smooth concrete theme.
Waiting on more filament to arrive and experimenting with PETG filament, which promises a smoother finish, faster printing, and more flexibility.

L(.)(.)king GOOD!  That's some VERY NICE WORK!

I primarily print with PETG.  Good Layer Adhesion and Smooth Prints will require you to Slow the Print Speed  Down to around 60%-75% of full speed.  For the Best Layer Adhesion and Print Smoothness Turn the Cooling Fans Off.  Other settings/adjustments (too numerous to list here) can also improve PETG prints.

It looks like you are using 64 sided cylinders... I almost always use the 'perfect circle' for cylinders and bores (holes) ...smooths things out a bit.

Dennis thanks for the "perfect circle" tip!   Youʻre right I have only used the basic shape cylinder in Tinkercad.

In a previous post you said "I did it backwards... I started out using 360 and then TinkerCad ...silly me!"   Iʻm curious about your reasoning - surely Fusion is more capable?

I usually end up making my own designs rather than copying... and, it's a lot faster for me to knock out a prototype in TinkerCad than in 360.  I will export/import the design into 360 for mesh fixes and contouring.  You can do an awful lot in TinkerCad.

For exact copies of items you can use a high quality raster image (.jpg, .png etc.) and convert them into vector images in Illustrator or Corel Draw.  Import those vectors into 360, Rhino or the like for sizing, mesh fixes and contouring etc.

Whoops!  Almost forgot... the Perfect Circle is what I use to make TPU (Shore 83A-85A) Traction Tires.

Update 8/31/24

Slow progress and getting side tracked along the way.  Modifications designed for top down assembly, avoiding reaching under the rail.  Using soft flexible connectors printed with TPU 95A filament.  I need more practice with this, my prints are not consistently firm and too much stringing.

Still using 1/2" MDF but added keyhole like slots to each adjoining side and using flush TPU keys to hold the sides together.  Also added a soft TPU bolt to fasten the MDF down to the top of the pier.  The goal was easy working access from the top side.  MDF flexing is a problem and I will need a support every 10" or about every section of track.  I like the thinness of 1/2" thick roadbed so I donʻt think moving to 3/4" plywood would retain the look Iʻm after, and plywood is not as easy to "machine".   Going to stick with MDF until I get trains running.

Update 9/12/24 - putting this project on vacation hold for 3 weeks while we take a Mediterranean cruise next week.  I am taking my laptop loaded with Autodesk Fusion - hoping for some time during the sea days to learn it.  I did spend a day tying out FreeCAD last week, but it did not work well for me on Mac OS.

Hereʻs an overview of my upper O72 loop that will use Atlas sectional track, this may not be the final track layout.  Iʻm pleased with how quickly I can try different options, itʻs like a "sectional" roadbed.

I have improved my printing with TPU-95, which Iʻm using for flexible roadbed joiners and hold-down bolts.  Smaller batches printed at 50% speed works best for me.  

Version 2 of my "roadbed system" has wiring channels added to the top pier for power drops.  These are hidden under the MDF roadbed.

Other changes include a hold-down bolt with recess attaching the top pier to the column, and threaded column base mating to threaded base pier.

My goal for switching to Fusion from Tinkercad is making revisions easier and faster.  I expect to revise everything to be more "prototypical".

I am making the MDF roadbed using traditional woodworking power tools, however I am planning designs using a CNC Router.

Thanks for looking!