Direct Answer
Steel detailing is the process of producing fabrication-ready drawings and models from an engineer's design documents. A fabricator needs it because general design drawings lack the precision required to actually cut, drill, and assemble steel members — piece marks, hole locations, weld symbols, and BOM are all products of detailing.
Full Explanation
Structural engineers produce design drawings that show intent — member sizes, loadings, connection types — but not the shop-level detail needed to make each part. Steel detailers translate that intent into piece mark drawings, erection plans, anchor bolt plans, and connection details. Each sheet is dimensioned to fabrication tolerances (typically ±1/16") and references the applicable codes (AISC, AWS, ASTM). Without proper detailing, a fabricator is guessing at bolt patterns and weld sizes, which is a recipe for failed inspections and costly rework.
What This Means for Your Shop
Every hour of fabrication depends on accurate detailing. Errors in hole locations, member lengths, or cope dimensions compound on the floor. Working with an experienced detailing partner like Tectonix means you receive IFC (Issued for Construction) packages that can go straight to your saws and drills without interpretation.
Common Mistakes
The most common mistake fabricators make is starting production from design drawings rather than approved shop drawings. Design drawings show nominal sizes; shop drawings show actual cut lengths including copes, setbacks, and connection plates. Running steel from design documents almost always creates rework.
Recommended Process
Receive design drawings → engage detailer → detailer produces anchor bolt plans first → steel erection drawings submitted for engineer review → approval received → IFC package issued → fabrication begins. Never cut steel before the IFC stamp.