Methodology · reviewed 2026-08-01
We label what was observed, calculated, assumed, and illustrated.
Our calculators are planning models, not black boxes. This page explains where the numbers come from and how pages are reviewed.
Who reviews the work
The site operator is a software developer and maker with direct experience designing, printing, costing, and selling physical products. That work includes small-batch FDM production, vendor quotations, and evaluating a transition from printed parts to injection molding.
We do not claim that one workshop's costs apply everywhere. Every calculator therefore leaves its core inputs editable and explains the formula used.
Four evidence labels
Values from the operator's work, anonymized or rounded when commercial details must remain private.
A visible equation that visitors can reproduce and replace with their own inputs.
Manufacturer or primary technical documentation used to support a setting or workflow.
A clearly hypothetical scenario used to show how a formula behaves, not a claimed measurement.
Anonymized field case
One real quote, with modeled scenarios kept separate
Review workflow
- Define the decision and identify every input with a unit.
- Write the formula and check that percentage fees and failure rates are applied to the correct base.
- Test zero, typical, and extreme inputs; prevent invalid divisions and duplicate costs.
- Compare the result with a manual worked example.
- Operator-review the page, its limitations, and its links before publication.
AI and editorial illustrations
AI may assist research organization, translation, editing, code development, and the creation of editorial illustrations. The operator reviews formulas, behavior, and final wording. AI-generated output is never presented as measured workshop data, and generated artwork is labeled as an illustration rather than a photograph.
Corrections and limitations
Material prices, energy rates, taxes, fees, machines, and workflows change. Results are estimates and are not accounting, legal, tax, or engineering advice. To report a material error, email dbwlstnwls0@naver.com.