The basic CUTL calculator prices a part as material plus cutting plus piercing, and a batch as unit cost times quantity. That means the price per piece is the same whether you make one part or one hundred. Extended cost calculation changes that.
It folds in the real fixed and indirect costs of a production shop (sheet changes, gas, consumables, equipment maintenance, overhead, markup, rush surcharge and shipping) and spreads them across the batch with the sheet nesting taken into account. The more parts that fit on a sheet, the cheaper the material and the sheet change become per part, so the per-piece price genuinely falls as the quantity grows. It falls through arithmetic, not through a manual discount.
This page is written for shop owners and estimators who already price parts in CUTL and want a true per-part figure for a real batch. If you are new to the platform, start with Getting started, and read Quoting and cost for how the basic per-part cost is built.
Why fixed and indirect costs must be spread
A cutting shop pays for far more than the sheet and the beam time. Rent, salaries, machine maintenance, lens and nozzle wear, gas bottles and utilisation losses all cost money whether you cut one part or fill a whole sheet. If you ignore them, your per-piece price is optimistic on small runs and leaves money on the table on large ones.
Extended calculation attributes each of these costs to the part in proportion to how much of the batch and the sheet it uses. A single part carries the full cost of a sheet change and a large share of overhead. Fifty parts nested on one sheet share that same sheet change fifty ways. This is why the price per piece drops as quantity rises, and why the drop is real rather than a marketing gesture.
Configure your inputs once, up front
Everything below lives under the top Dictionaries menu. Work through it top to bottom the first time. Once the dictionaries are filled in, a calculation takes about a minute.
Materials
Open a material, or create one.
| Field | Purpose | Required |
|---|---|---|
| Price per 1 m² | material cost per part | Yes |
| Sheets tab, Add sheet size (Width, Height in mm) | the sheet sizes used for nesting; common materials come with standard sizes pre-filled | Yes, at least one (usually already there) |
| Default checkbox on a sheet | pre-selects this sheet automatically | Recommended |
If you only know the price per kilogram, convert it to a price per square metre with the cost calculator first.
Equipment
Open a machine and use the Cost and time tab.
| Field | Purpose |
|---|---|
| Hourly cost | the machine's main rate |
| Monthly maintenance cost and Average working hours per month | together they give the equipment-maintenance share per part |
| Sheet change time (s) | drives the sheet-change cost |
| Assembly time per part (s) | setup time per part, shown as the "+ N s setup" in the maintenance line. Set it to 0 if there is no per-part setup |
On the Consumables tab, add each wearing item (lens, nozzle, lamp and so on):
| Field | What to enter |
|---|---|
| Name | for example "Lens" |
| Cost | price of one piece |
| Wear metric | how lifetime is measured: hours, pierces or metres |
| Lifetime | how long it lasts in that metric. Must be greater than 0 |
The Sheet change time by material tab is optional. Use it only when a particular material makes the sheet change slower or faster than the machine default, for example a heavy plate.
Cutting modes
| Field | Purpose |
|---|---|
| Cut time (s/m) | cutting time per metre |
| Pierce time (s/pc) | time per pierce |
| Cut price (per metre) | cutting rate |
| Pierce price (per pc) | pierce rate |
| Gas and Gas consumption (L/metre and/or L/min) | only if the cut uses gas |
Leave the gas fields empty for mechanical equipment.
Gases
Fill this in only when a cutting mode uses gas. Enter the Bottle price and Bottle size; the price per litre is derived from those two figures.
Organization
Open your organisation and use the Cost profile tab.
| Field | Purpose |
|---|---|
| Fixed monthly costs | rent, salaries and other overhead |
| Machine hours per month | how many hours a month the machine actually runs |
| Load (%) | real equipment utilisation |
| Default rush (%) | pre-fills the rush field in the calculation dialog |
If you price shipping, add rules under the Shipping / freight section: choose a Rule type, a Zone code, a Base cost and a Variable cost. The zone code is what you later pick under Shipping zone in the calculation.
Running an extended calculation
In the dialog:
| Field | What to do |
|---|---|
| Quantity | parts in the batch (required, 1 or more) |
| Sheet | pick a sheet size (required) |
| Spacing (mm) | the gap between parts for nesting |
| Calculate | runs auto-nesting and fills Parts per sheet for you, or type Parts per sheet by hand |
| Markup (%) | your trade markup |
| Rush (%) | rush surcharge, pre-filled from the cost-profile default |
| Shipping zone | pick a zone if shipping is needed. It is empty or disabled when no zones are configured |
The number of parts per sheet comes from nesting automatically, or you can enter it by hand, so a missing nesting layout does not block the dialog. See Nesting for how the layout is produced.
The price scale and optimal quantity
The dialog shows a price scale: the client price per piece at 1, 5, 10, 25, 50 and 100 parts, alongside your requested quantity and the optimal quantity. It makes the volume effect visible at a glance.
Optimal quantity is the largest batch at which the per-piece price still drops meaningfully. CUTL walks up the quantity axis to a ceiling (1000 parts by default), following the points where a new sheet is needed, and stops once the saving from one step to the next falls below 1%. The result also reports how much cheaper the optimal per-piece price is against a quantity of one. Press Apply optimum to drop that quantity straight into the Quantity field.
Reading the cost breakdown
The result is split into collapsible blocks:
- Direct costs: material, cut and pierce, gas, sheet change. The "Based on N parts per sheet" caption reflects the nesting.
- Indirect costs: consumables, equipment maintenance, overhead.
- Cost per part: the total of the two blocks above.
- Client price with markups: cost times markup times rush, with the client price per piece and the client batch total.
- Shipping: if configured, plus the final total with shipping.
Under each amount there is a plain-language formula line, for example an equipment servicing line reading "(cutting 7.49 s + setup 1 s) times rate 0.03/s". Here cutting 7.49 s is the part's cutting time, setup 1 s is the assembly time per part from the machine card, and rate 0.03/s is the cost of one second of servicing. Overhead is computed from cutting time only, without setup, which is why its formula line is shorter.
Saving with "Remember"
Remember at qty N pcs saves the calculation as a separate row on the part card. The part's base price is not changed. You can keep several saved calculations, mark one with a star, and the starred one is shown in the parts list.
A saved calculation is a snapshot taken at the moment of saving. It is frozen and never recalculated, even if your dictionaries change afterwards. Saved calculations appear in the Saved quotes table on the same tab, showing sheet size, parts and price, each with view and delete buttons.
The "Incomplete calculation" banner
While the Sheet is not selected or Parts per sheet is not set, a red Incomplete calculation banner stays on top. This is expected. Finish those two fields, or press Calculate. The message under the banner names exactly what is missing:
| On-screen message | What to do |
|---|---|
| Specify the sheet size and parts per sheet, or run nesting | Pick a Sheet and press Calculate, or type Parts per sheet |
| Organisation cost profile is not filled in | Dictionaries, Organizations, Cost profile: fill in fixed costs, machine hours and load |
| Equipment rate is not set | Dictionaries, Equipment: set Hourly cost and/or maintenance |
| Gas in cutting mode has no price or rate | Set Gas consumption in the cutting mode and Bottle price/size under Gases |
| Consumable lifetime is 0 or below | Dictionaries, Equipment, Consumables: set a Lifetime greater than 0 |
| Zone specified, rule not found | Add a shipping rule for the selected zone, or clear the zone |
| Select a cutting mode for the part and save | On the part card, pick a cutting mode and save the part |
| Calculation incomplete, check the reference data | Walk back through the input sections above |
Pre-flight checklist
Run through this before your first extended calculation:
- Material has a price per 1 m² and at least one sheet size, preferably marked default.
- Equipment has an hourly cost, maintenance figures, an assembly time per part (0 if none), and consumables with a lifetime above 0.
- Cutting mode has cut and pierce times and prices; gas only if the mode uses gas.
- Gases have a bottle price and size, only if the mode uses gas.
- Organisation cost profile has fixed costs, machine hours and load; shipping rules only if you price shipping.
- The part has a cutting mode selected and is saved.
After this, extended calculation runs correctly and the banner should not appear.
FAQ
Why is my per-piece price different at 10 parts than at 100 parts? That is the whole point. Fixed and indirect costs (sheet change, overhead, equipment maintenance, consumables) are spread across the batch, and nesting decides how many parts share each sheet. More parts per sheet and a larger batch mean a lower price per piece, by arithmetic rather than a manual discount.
Does extended calculation change my normal calculation or my saved quotes? No. The basic material, cutting and piercing cost and the markup logic are unchanged, and saved calculations are frozen snapshots that are never recalculated.
The banner will not go away. What is wrong? Read the message under the banner. It names the exact missing data. Most often it is a sheet or parts-per-sheet that is not set, or an organisation cost profile that is not filled in.
I do not have a nesting layout yet. Can I still run the calculation? Yes. Press Calculate to run auto-nesting, or type Parts per sheet by hand. A missing layout does not block the dialog.
Overhead is missing from my breakdown. The overhead rate is derived from the organisation cost profile (fixed monthly costs, machine hours and load). If any of those is empty or is zero or below, overhead is excluded and a warning is shown. Fill in the cost profile under Dictionaries, Organizations.
To see how the parts-per-sheet figure that drives all of this is produced, read Nesting next.