SPM Cycle Time Planning: What to Measure Before You Order

“How many parts will it make in a shift?” is usually one of the first questions in an SPM enquiry. It is a fair question. A production team needs a number it can use for scheduling, staffing and deliveries.

The answer becomes more useful when everyone agrees what the timing includes. A drilling operation may finish quickly, while loading the next component, confirming its position and checking the finished part take additional time. Those details belong in the discussion before the machine specification is signed off.

This guide explains how to approach SPM cycle time planning with observations from your actual process. It is a starting point for a practical conversation with your special purpose machine manufacturer.

1. Agree where the cycle starts and ends

Start with a simple question. Are you measuring the automatic operation, or the time between two consecutive finished parts leaving the station? Both measurements can be useful, but they answer different questions.

Write down the start event, the finish event and the number of parts produced per cycle. For a multi-station machine, also distinguish the time a part spends inside the system from the interval between finished parts once the machine is running steadily.

A short video of the existing process, where recording is permitted, can help the production team and supplier discuss the same sequence. Note waiting periods as well as active operations. An observation sheet with a clear timing boundary is more useful than a single unexplained target.

2. Include loading, locating and unloading

Watch how the operator actually handles the component. Is it already oriented in a tray? Does it need turning before it sits in the fixture? Where does the finished part go? Small handling tasks can become a noticeable part of a short production cycle.

Separate these tasks in your timing record. Some may happen while the machine runs; others must wait until the previous operation is complete. Ask the supplier to explain which activities overlap in the proposed design. Adding every task together can overstate the cycle, while leaving manual tasks out can make the target unrealistic.

Fixture layout belongs in this review too. Our guide to SPM fixture design and part location explains the questions worth raising about how components are presented and held.

3. Test the part mix you expect to run

The easiest component in the range may give an encouraging demonstration. It does not tell you what happens with a heavier part, a different hole pattern or a variant that needs another operation.

Prepare a part list with drawings, sample quantities, material details and the expected production mix. Identify the variants that are likely to take longest or require different handling. Ask how the cycle target applies to each one.

Batch changes need their own allowance in the production plan. A running cycle time does not describe the time spent changing tooling, selecting a recipe or approving the first part of the next batch. For a machine serving several components, review our SPM changeover planning questions alongside the cycle-time discussion.

4. Check the handoffs on both sides of the machine

A machine can be ready to work and still be waiting for a component. It can also complete an operation and have nowhere to send the finished part. Look at the stations immediately before and after the proposed SPM.

Ask who replenishes input trays, how parts arrive, and what happens when the receiving process pauses. If conveyors or automatic handling are included, agree on the transfer sequence and the signals that confirm a part can move.

These questions help define the scope of the supply. They also prevent a quotation for the machine alone from being mistaken for a complete production line solution. Share a layout showing nearby equipment, storage positions and the intended material route.

5. Keep inspection and output assumptions visible

Good parts are the output that matters to production. Explain which checks happen automatically, which require an operator and whether inspection is carried out on every part or on a defined sample.

For illustration, a one-part cycle of 30 seconds corresponds to a theoretical 120 parts per hour during uninterrupted running. That calculation is not a promise of hourly dispatch output. The production plan must separately allow for the agreed working time, stoppages, changeovers and parts that do not pass inspection.

Use your own operating records when making these allowances. Keep the theoretical machine rate and the planned number of accepted parts per shift clearly labelled in the enquiry. That makes later comparisons much easier.

6. Agree how the cycle will be demonstrated

Before placing the order, agree on the trial conditions. Specify the component variants, material supply, staffing, inspection method, trial duration and how interruptions will be recorded. Ask for results across repeated cycles rather than relying on the quickest individual run.

Record the timing boundary alongside the measured result. If loading is manual, document that arrangement. If a trial uses a different part supply method from your factory, note the difference and discuss its effect before accepting the result.

A useful enquiry pack brings these details together: drawings and samples, required output, observed task timings, part mix, layout and a proposed acceptance method. Your supplier can then assess a specific production requirement.

Discuss your SPM requirement with JBDS Power

Planning a dedicated drilling, assembly, testing or handling station? Explore JBDS Power special purpose machine solutions and share your process requirements with our team. Bring the current operation, part details and output target so the discussion can start with the work your machine needs to do.

Images illustrate typical planning scenarios.