Thought this was kind of a cool application of 3D printed fitting blocks for pre mock-up & sizing of interweaving header pipes. Of course you still have to do all the real metal cutting & welding fabrication, but the 'lego blocks' provide angles & angular offsets. Makes me wonder how they did it the bad old days. Maybe they had 'woodies'? LOL
https://www.thefabricator.com/artic...esswork-out-of-modeling-custom-header-systems
https://www.thefabricator.com/artic...esswork-out-of-modeling-custom-header-systems