A few weeks ago I got a new FDM printer that I'm liking a lot, so I thought I'd push the limits as I'm known to do. My idea is to get a single line extrusion from the .4mm nozzle to draw catenary. It took a lot of adjusting on the printer's profile to get repeatable results, and a few iterations of the design. Here are the important parts and how they assemble: I went with three layers .2mm each for a total thickness of .6mm. I tried other thicknesses but .6mm offered the best compromise of looks/rigidity. Rigidity being the main factor as manipulating long spans gets pretty wriggly. Here are a few parts assembled: And a "height check" with a model stand-in. I apologize for the Frankenstein Little Joe, it was put together with junk parts laying around but served its purpose: I don't know if this will ever make it on a layout but it was fun to give it a try. I may do a small diorama for a prettied up Little Joe, or do a small section on my dad's layout which is forever in early construction phase. Catenary is a tricky detail to add since the spacing has to be spot on. I may be able to adjust the design more to allow for spacing slop. Happy 3D Printing Everbody -Mike Note: Edited to correct the thickness to .6mm. I stated originally they were .8mm but that was incorrect.
Dang! Thats as good if not better then the Viessman metal stuff . . . When will you start selling it?
Thanks for the comments - I scaled the catenary lines to Z tonight just to see what I'd get. The spans between the two main lines are so short at 1:220 that they don't have enough purchase on the bed. That results in them just blobbing everything up as the nozzle runs over them and knocks them off. I still want to try a few more design adjustments though to see if I can reduce the installation effort required to put it together. It's always a slow process with me so who knows if or when I'll be satisfied with the results. Best we can do is stay tuned... Mike
