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July 9, 2025 · The Bloomfield Team

The Top 5 Time Wasters on the Average Shop Floor

A machine shop running two shifts across ten CNC machines has roughly 4,160 available production hours per month. In a well-run operation, 55 to 65% of those hours produce chips that become revenue. The rest disappears into setups, changeovers, maintenance, and the five categories of wasted time described below.

The gap between 55% utilization and 75% utilization on the same equipment, with the same team, represents approximately $480,000 in annual revenue for a shop billing $120 per spindle hour. Nobody installs new machines to close that gap. They fix processes.

1. Searching for Information

The single largest time waster on most shop floors has nothing to do with machining. Operators spend an average of 45 minutes per shift looking for information they need to run the job in front of them: setup instructions, drawing revisions, tooling notes, material certifications, customer-specific requirements.

That information exists somewhere. In the ERP. In a binder on the shelf. In an email the quality manager sent six months ago. In the head of the guy who ran this job last time. The search time is a direct function of how scattered the data is across systems and people.

At 45 minutes per shift across two shifts on ten machines, a shop loses 300 hours per month to information searches. At a loaded labor rate of $45 per hour, that is $13,500 per month spent on finding things instead of making things. For a closer look at how production data should be organized and delivered, see our guide to production visibility in manufacturing.

2. Excessive Setup and Changeover Time

Setup time is a fact of job shop life. Every new work order requires a changeover: pulling fixtures, loading tooling, proving out the first part. The wasted time is in the setups that take longer than they should because the operator is working without adequate documentation from the last time the job ran.

A shop running 15 changeovers per day with an average setup time of 50 minutes spends 12.5 hours daily in changeover. If better documentation and tooling organization could reduce average setup time to 35 minutes, that saves 3.75 hours per day, or roughly 80 hours per month. That is nearly two full weeks of additional production capacity from the same machines with the same crew.

3. Rework and Scrap on First-Run Parts

First-article failures cost double: the time and material of the scrapped parts plus the time to diagnose and rerun. Shops that track first-run yield closely typically find that 60 to 70% of first-article failures trace back to one of three causes: outdated or incomplete setup documentation, tolerance misinterpretation on the drawing, or material that was substituted without updating the program.

All three are information problems. The machinist made the part as instructed. The instructions were wrong. When the correction lives only in someone's memory from the last time this job ran, the same failure repeats every time a different operator picks up the work order.

4. Waiting for Material

A machine sits idle because the material for the next job has not arrived, has not been cut to size, or has not been located in the stockroom. Material wait time is partly a purchasing and scheduling problem, but it is also an information problem. The production schedule said the job starts at 2:00 PM. The material was ordered based on a lead time that changed three weeks ago and nobody updated the system.

Shops that connect material availability data to their scheduling process, even in a basic spreadsheet, reduce material wait time by 30 to 50%. The ones that let scheduling and purchasing operate as separate workflows accept the gap as a cost of doing business.

5. Mid-Shift Schedule Changes

A rush order comes in. The production manager reshuffles three machines. The operators on those machines stop their current jobs mid-run, tear down setups, and switch to the rush work. The original jobs, now partially complete, sit in queue until the rush clears. When they come back, the operator needs to re-setup and re-prove a job that was already running.

Some schedule changes are unavoidable. A key customer calls with an emergency and you accommodate them. The wasted time is in the avoidable changes: the ones that happen because the shop does not have visibility into what is running, what is due, and what the real cost of a schedule change is before the decision gets made.

The Common Thread

Four of these five time wasters are information problems. The right data, delivered to the right person, at the right moment. Setup documentation from the last run. Material availability in real time. Job history that travels with the work order. Schedule impact analysis before a change is made.

The machines are not the bottleneck. The data is. Every hour recovered from these five categories goes directly to the bottom line, because the machines, the operators, and the overhead are already paid for. The only variable is how many of those paid hours produce parts that ship.