take auto cad model of stair assembly and create file ready for 3D printing. model includes the following components 2 x stair flights. 1 x landing, 2 x handrails. 4 x handrail bends. 1 x bracket to attach handrail. the section sizes will need to be thickened so the final model has sufficient thickness
I can do your project in a couple of days no problems. I will do it in Solidworks & can produce 3D stl files & also any other format you need. I have been in the plastics industry for over 30 years.