How do I find the bottleneck in my factory?

Look for the work center with the longest queue of waiting jobs, the highest utilization, and the most overtime. If product mix is stable, the bottleneck is usually obvious. In high-mix environments it shifts daily, so you need a scheduler that tracks queue depth and throughput in real time.

Can a bottleneck move?

Yes, especially in high-mix low-volume shops. A different product mix or a new hot job can shift the constraint from a 5-axis mill to inspection to outside heat treat within a single week. Static capacity analyses miss this; a dynamic scheduler tracks it as it moves.

Should I always schedule to the bottleneck?

Yes for throughput, but with stability. Drum-Buffer-Rope (DBR) is the canonical pattern: schedule the bottleneck (the drum), buffer it with staged work, and release upstream work only at the rate the bottleneck consumes it. This prevents WIP explosion at non-bottlenecks.

Bottleneck — Manufacturing Scheduling Glossary

Definition

A bottleneck is the resource — machine, operator, tool, or process step — whose capacity is the lowest in the production flow and therefore sets the upper limit on factory throughput. By the Theory of Constraints, the bottleneck determines the system's output; any improvement to a non-bottleneck resource yields no additional throughput. The bottleneck can shift as product mix, priorities, or staffing changes.

Why it matters

Every hour lost at the bottleneck is an hour of throughput lost for the whole factory. Most shops have at least one bottleneck operating at 95%+ utilization while non-bottlenecks run at 50–60%, yet they invest equally across all resources. Identifying and protecting the bottleneck — with a buffer of staged work, dedicated setup, and priority labor — is the single highest-ROI scheduling decision.

Common failure mode

A planner schedules to keep every machine busy, including non-bottlenecks. Non-bottlenecks build WIP in front of the bottleneck, which still runs at the same rate. WIP grows, lead times stretch, and the planner feels productive while throughput stays flat. Worse, the real bottleneck shifts and nobody notices until OTD slips.

How Skody approaches it

Skody continuously identifies the current bottleneck by looking at queue depth, throughput rate, and downstream demand. Operators see the bottleneck flagged in the dashboard with current load and projected exhaustion time, and the scheduler protects bottleneck time by sequencing setups to minimize changeover at the constraint.

Constrained Resource

Any finite resource that limits how much work the factory can complete in a period.

Finite Capacity Scheduling

Scheduling that respects the real, limited capacity of each machine, operator, and tool.

Queue Time

The time a job waits in front of a work center before it actually starts processing.

Work Center

A grouping of one or more machines or stations that share routing and capacity.

Manufacturing Variability

The unpredictable variation in setup, run, and queue times that makes plans drift from reality.