Spacecraft . 2d truss jig

Posted on by dkoa

Mild steel angle bar is liable to twist or bend before the truss is triangulated; to ensure that each octet truss you make is straight (±1 mm) use a straight and square metal jig with wood board forming welding bed (will burn over time, flip over before replacing). Use clamps to secure 2d truss frame to jig, and push metal against wood plate of jig with a nonconductive pipe or wood stick.

Welding: Tack weld first throughout to assemble octet truss, then complete full weld once all metal elements are held in contact. Usually a small amount of grinding required to clear sharp edges. Apply hardener coat to seal and spray 3-6 coats of automotive paint. Paint damage possible (e.g. scratches) during transport and assembly; paint touch-up work may be done after assembly.

use clamps to secure 2d truss frame to jig, and a nonconductive stick (preferably wood) to push metal against wood plate of jig.

2d truss jig spacer2d truss jig side viewweld flat bar ladder into 2d truss frame5 weld sides to 2d truss frameuse clamps to secure 2d truss frame to jig, and a nonconductive stick (preferably wood) to push metal against wood plate of jig.5 weld safety first6 weld pyramid chain into 2d ladder truss7 weld invert pyramid to angle bar at vertices8 semi-octet trusses should stack interlock9 7 1.5in semi-octet trusses welded, load to paint

finished octet trusses sprayed and loaded in truck bed
finished octet trusses sprayed and loaded in truck bed

Octet truss drill template

Posted on by dkoa

Use a template for drilling holes in octet truss, to ensure that all holes are the same and identically located. Print on paper first,then trace or laminate onto cardboard and punch hole centers per template guides. Provided octet truss welding work is standard, dimensional tolerance of ±1 mm is achievable. Square face bolted connection is 20×20 cm, with holes of sufficient tolerance for no. 17 bolts. Drill templates are here in PDF: octet truss face joint, octet truss face joint -alt (print to A4 size sheet).

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