Plastics: you know your theoretical cycles, not your real ones

Between mould changes, purges and start-up scrap, the gap between the quote and reality widens without anyone measuring it.

Thirty minutes, no commitment

Describe your workshop. I'll tell you where I would start and what I would leave alone.

In an injection shop, performance is decided in seconds of cycle time and minutes of changeover. Your presses are finely controlled, your setters know their machines, and yet the real cost of a part number remains an estimate.

The reason is simple: the numbers that matter — real cycle, start-up scrap rate, actual mould change duration, material consumption per part number — sit either inside the press or in a notebook, and never in the same place as the quote that uses them.

What I see in your workshops

The quoted cycle time dates from the first trial

It was measured during mould qualification, in ideal conditions, with the most experienced setter. In routine production, with regrind in the mix, an ageing mould and a different operator, the real cycle is longer. That gap is never fed back into estimating.

Start-up scrap is thrown away without being counted

The first parts after a mould change or a purge go to the granulator. Everyone knows that is normal; nobody knows what it amounts to over a year, or whether one part number produces three times more than another. Yet that is the figure that would justify grouping runs differently.

The real duration of mould changes is unknown

People say « about forty-five minutes ». The real spread runs from thirty minutes to two hours depending on the mould, the shift, and whether the tool was put away clean. Without measurement, no changeover reduction programme can be prioritised.

Mould history lives in a tooling binder

Cycles since last maintenance, repairs, reworks, blocked cavities. Preventive mould maintenance is triggered by observed wear or by breakage, while the cycle counter is sitting there on the press.

Material and colour blends are not tracked by batch

Percentage of regrind, colourant batch, virgin material batch, drying time. When an appearance defect shows up at the customer three weeks later, tracing the cause means cross-referencing information that was never recorded together.

Where I would start, in this order

The order matters more than the list. Here it is as I would propose it after the audit, unless the two days on site show otherwise.

1
Your production figures are written on a sheet next to the machine
This is the starting project in plastics, unlike other sectors. Your presses already count cycles and log their stoppages: retrieving that gives you the real cycle, the start-up scrap and the changeover duration — the three numbers missing from your cost price.
collect machine data and real production times
2
Rebuilding a traceability file takes you half a day
Material batch, colourant batch, regrind ratio, mould and cavity used: that link is what lets you contain an appearance or strength problem to a narrow scope instead of reworking three weeks of production.
automate ISO 9001 traceability and audit preparation
3
Your production schedule is a spreadsheet rebuilt every Monday
Once real cycles and changeover times are measured, press load becomes genuinely calculable. Grouping runs that share a material and a colour becomes a costed decision rather than a habit.
move from a spreadsheet schedule to reliable machine load
4
Your quotes depend on one person and go out too late
In injection moulding, price turns on cycle, cavitation and scrap rate. Feeding real values back into estimating is the only way to stop repeating the error in the first quote.
automate estimating and quote generation

What I don't do

What I do not do in a plastics shop:

I do not set your presses and I do not modify your injection programs. I read the information they produce; I do not touch them.
I do not do tooling design or simulation.
I do not do predictive maintenance on presses. Tracking the cycle counter per mould — simple preventive work — delivers more and costs a hundred times less.
I do not work on machine safety functions or guarding.

The questions I get asked

Our presses are different makes and generations.

That is the norm and it is not a blocker. Recent presses often expose a standard protocol; older ones provide at minimum an end-of-cycle signal usable with a simple sensor. The feasibility survey, press by press, is part of the two-day audit.

Do the presses have to be connected to the internet?

No. Everything stays on your local network. The data does not leave your premises without an explicit decision from you.

What does it cost and how long does it take?

Two-day audit at €1,500, including a survey of what can be retrieved from your machine park. A data-collection project across five to ten presses lands between €10,000 and €15,000 fixed price, excluding sensors bought directly, delivered in three to four weeks.

Will automatic counting be used to monitor operators?

If that is how the project is presented to the shop, it will fail, and it will deserve to. The measurement is about the machine and the part number, not about people. It is a position I hold, and a point to clarify with your employee representatives before starting, not after.

Who owns the code?

You do, with the wiring diagrams and the documentation. No subscription, no per-machine licence.

Let's talk for thirty minutes

You describe your flow, I tell you what can be automated, what cannot, and where I would start. If I'm not the right person, I'll say so during the call.