Customizable and extensible truss

thingiverse

A customizable truss module that can be joined and extended to arbitrary length. To be used with "Okkake Daisen Tsugi" (https://www.thingiverse.com/thing:5392796), a Japanese traditional wood joinery technique, for firm interlocking. I've used this design to construct several trusses of 1.5 meters long (see picture, a big plotter with a vertical truss rail). End modules (with three joints only on one side and of desired length and shape) are not included in this distribution but should be easy to design with simple intersection and union operations. Download both truss.scad and tsugite.scad (from https://www.thingiverse.com/thing:5392796) and first find (and record) the right gap parameters by the test printing of tsugite.scad. Then put the recorded numbers to the "overriding parameters for tsugite joints" section of truss.scad. (Alternatively, you can directly change the parameters of tsugite.scad, in which case comment out corresponding lines of truss.scad to avoid overriding.) Plugging of joints is not essential if the interlocking is firm enough, but is recommended especially when the load is not light and static. Square pads on the ends of joints are enabled by default because prints of this size and infill (which is supposed to be higher than models) tends to warp even when printed with PLA and PETG. If pads are not needed, set the variable "pad" to 0.