Oval Staircase AutoCAD Manufacturing Drawings

About the project

Project I require a detailed 3D CAD model and complete fabrication drawing package for a custom oval/elliptical staircase for a residential house in NSW, Australia. An approved architectural A3 drawing is attached. It contains: * 1:50 staircase plan with dimensions * 1:50 south elevation with levels * 1:50 stair section through the landing * 1:20 tread/nosing detail * 3D architectural sketch * reference photograph showing the intended finished appearance The architectural design and principal staircase geometry are established. The objective is to develop this design into a practical steel staircase assembly with sufficient detail for engineering review and subsequent fabrication. Construction Concept The staircase consists of two curved/elliptical flights separated by an intermediate landing. The finished staircase will have timber treads and architectural finishes. The primary structure is intended to be a concealed central steel spine, hidden within plasterboard/flexible board. The spine will likely be fabricated in approximately three sections to simplify manufacture, transport and installation, with suitable connections between the sections. There are three principal structural support locations: 1. Lower connection at ground-floor level. 2. Intermediate connection adjacent to a structural steel wall column. 3. Upper connection at the suspended first-floor slab/structure. The design should take fabrication practicality, transport, installation and access for assembly into consideration. Scope 1. Complete 3D Staircase Model Create a complete, accurate and editable 3D CAD model based on the supplied architectural drawings, including: * overall oval/elliptical staircase geometry * both curved flights * intermediate landing * concealed central steel spine * steel tread support brackets * timber treads * landing structure * lower mounting connection * intermediate wall/column bracket * upper floor/slab connection * fabrication splices between spine sections * connection plates and stiffeners * bolts and other relevant hardware * balustrade and handrail geometry where required to coordinate the staircase assembly The architectural dimensions and design intent should be followed closely. Final critical dimensions will be checked against as-built site measurements before manufacture. 2. Individual Stair/Tread Geometry Detailed dimensions must be provided for each individual stair tread, rather than relying only on general or typical dimensions. The model and drawings should clearly establish for every tread: * tread number/reference * elevation * position relative to the staircase geometry * tread width * tread depth/going * curved or tapered geometry * relevant angles * inside and outside dimensions * relationship to the central spine * position and geometry of its steel support bracket * fixing locations * timber thickness * nosing geometry Each tread should be individually identifiable in the CAD model and drawing package so that its geometry can be fabricated and checked independently. 3. Tread Nosing and LED Lighting Detail The architectural design incorporates concealed LED strip lighting beneath the edge/nosing of the timber treads. The supplied architectural drawing includes a tread/nosing detail showing the intended recessed/cut-out arrangement. This detail should be incorporated into the 3D model and fabrication drawings, including: * recess/cut beneath the tread edge for the LED strip/profile * dimensions and position of the recess * coordination with the tread support structure * sufficient clearance for the LED strip/profile and associated installation * consistent positioning across the staircase The timber tread drawings should clearly show the LED recess so that each tread can be manufactured accordingly. 4. Steel Fabrication Detailing Develop the complete steel assembly, including: * central spine sections * tread support brackets * landing structure * lower support connection * intermediate wall/column connection * upper floor connection * splice connections between fabricated sections * connection plates * stiffeners * bolts and hole patterns * welds * material/profile call-outs * plate thicknesses * bend radii where applicable * practical assembly and installation details The steelwork should be designed with practical fabrication, transport and on-site installation in mind. 5. Fabrication Drawings Produce a comprehensive drawing package including: * overall staircase assembly * plan views * elevations * sections * exploded views where useful * steel spine assembly drawings * individual steel part drawings * individual tread drawings * landing drawings * bracket drawings * connection details * dimensions and tolerances * hole locations and patterns * weld symbols and details * material and profile specifications * surface finish information * fastener specifications * component/part numbers All components should be uniquely referenced so that drawings, CAD parts and the bill of materials can be cross-referenced. 6. Bill of Materials Provide a consolidated BOM containing, as applicable: * unique part number * description * quantity * material * section/profile * plate thickness * relevant dimensions * associated drawing/reference The BOM and drawing component tags must correspond one-to-one. CAD Software and Deliverables Autodesk Inventor, SolidWorks or equivalent professional mechanical/structural 3D CAD software is preferred. AutoCAD may also be used where appropriate. Final deliverables must include: * complete native editable CAD source files * all referenced parts and assemblies * STEP model of the complete staircase assembly * DWG fabrication drawings * DXF files for laser/plasma/waterjet-cut components where appropriate * print-ready PDF drawing package * complete bill of materials Native editable CAD files should also be supplied at agreed project milestones. Project Stages The project will be awarded on a fixed-price basis using milestones. Milestone 1 – Overall Geometry and Concept Model Reproduce the staircase from the architectural drawing and establish: * overall 3D geometry * elliptical flights * individual tread positions * risers and levels * intermediate landing * initial concealed steel-spine arrangement * principal support locations The model will be reviewed before detailed fabrication work proceeds. Milestone 2 – Detailed Assembly Develop: * steel spine sections * individual tread geometry * tread brackets * LED/nosing detail * landing structure * support brackets * splice connections * connection plates and associated steel components Milestone 3 – Complete Fabrication Package Complete: * assembly drawings * individual part drawings * individual tread drawings * connection details * dimensions and tolerances * weld details * BOM * DWG/DXF files * STEP assembly * PDF drawing set * complete native CAD project Reasonable revisions arising from review should be included within each milestone. Experience Please provide examples of previous work involving: * curved, elliptical or helical staircases * fabricated structural steel * curved or compound steelwork * welded assemblies * steel connection detailing * timber/steel staircase construction * fabrication/shop drawings * Autodesk Inventor, SolidWorks or comparable 3D mechanical CAD I am particularly interested in seeing actual fabrication/shop drawings and the underlying fabricated structure, rather than architectural renders alone. When Responding Please review the attached architectural drawing and briefly answer: 1. Which CAD package would you use? 2. Have you previously detailed curved staircases or comparable fabricated steel structures? 3. How would you propose fabricating and dividing the concealed curved steel spine for transport and installation? 4. How would you establish and document the unique geometry of each individual tread? 5. What native CAD and interchange formats will you provide? 6. Have drawings you produced previously been used directly by steel fabricators? Generic proposals that do not demonstrate an understanding of the attached staircase will not be considered.

Skills required