Direct Answer
A realistic fabrication schedule is built from the bottom up: identify all piece marks, group by assembly complexity, estimate shop hours per assembly type, apply your shop's capacity (available hours per week), then sequence around detailing milestones and erection constraints. Add buffer for material delivery, revision turnaround, and inspection holds.
Full Explanation
Key inputs to a fabrication schedule: (1) Total piece count and estimated shop hours by type (simple beam, complex assembly, moment connection, misc. steel). (2) Shop capacity — how many crew hours per week, accounting for other projects running simultaneously. (3) Material delivery dates for long-lead sections. (4) IFC milestones — you can't fabricate until drawings are approved. (5) Erection sequence — the erector needs columns first, then beams in the sequence they're being set. (6) Inspection hold points — special inspection may slow production at welding and bolting stages.
What This Means for Your Shop
Schedule is where you win or lose on a steel project. A realistic schedule protects you from liquidated damages; an optimistic schedule creates a crisis. Involve your shop foreman in schedule development — they know how fast your crew actually works, not just how fast the quote says they should.
Common Mistakes
Building a schedule that assumes 100% shop efficiency. Real shops deal with machine downtime, welder absenteeism, material delays, and inspection holds. A realistic efficiency factor is 75–85%.
Recommended Process
Use a production management system (even a spreadsheet) that tracks each assembly from 'raw material received' through 'shipped.' Update weekly. When actual progress deviates from the schedule by more than 10%, investigate the cause and revise the schedule, notifying the GC immediately.