How we make this site
PourMath has one rule: a number either traces to a document the manufacturer publishes, or it is not on the page. This page explains how that works in practice, including the parts that are automated and the parts a person does.
1. Product values come from manufacturer documents only
We use three kinds of source, all published by the manufacturer itself:
- Technical data sheet (TDS): mix ratio, pour depth, pot life, cure times, viscosity.
- Safety data sheet (SDS): hazard statements, protective equipment, specific gravity.
- Official product page or instructions: used when the TDS is silent and the manufacturer states the value elsewhere.
We do not use retailer listings, marketplace pages, forums, videos or other sites’ tables. Each document is downloaded and kept on file with the date it was accessed, and each value in our database stores a short quotation from that document. An automated check confirms every stored quotation still appears in the saved copy of the document, so a value cannot drift away from its source.
2. Values are copied as published
A value keeps the units and test conditions the manufacturer printed, for example a pot life measured on a 100 g mass at 77 °F. We do not convert a value and then present the conversion as the manufacturer’s figure, we do not average across products, and we do not fill a gap from a similar product. If a value is not published, the page says “not published”.
When two documents from the same manufacturer disagree, the product page shows the TDS value and notes the disagreement.
3. Calculators show their work
Every calculator page shows the formula, the assumptions and a worked example. The math lives in small functions with automated tests covering unit conversions (inch, gallon and pound definitions are exact), edge cases and invalid input. Calculators that use product data refuse to answer when the needed value is not published. For example, the mix ratio converter will not give a by-weight split for a product that publishes neither a weight ratio nor the specific gravity of both parts.
Calculators never adjust published cure times for temperature. Data sheets state the conditions a time applies to, and we show those conditions with the result instead of extrapolating. When the conditions do not match your project, for example a wait measured on a 25 mm casting when your layers are 13 mm, the layer planner shows the published wording and does not calculate a schedule.
When a product’s documents give more than one depth limit, the planner uses the published limit only if it is the strictest one. If a document also gives a smaller limit for a particular application, automatic planning is suspended for that product and the page says why, rather than picking a number for you.
Each calculator result lists the document every value came from, field by field: a mix ratio may come from the TDS while a specific gravity comes from the SDS. Switching between US and metric units does not change a result: the exact values are kept, and only the displayed numbers are rounded.
4. Writing and review
Guides and explanations are drafted with AI assistance from the sourced material, then checked by the site owner before publication. Each page carries a review flag in its source file. The publishing script refuses to publish a page that has not been marked as reviewed. Pages are published in batches, and the date shown on a page is the date it actually went live.
5. What we have not done
We have not tested the products in a workshop or a lab. Nothing on the site describes a test, a pour or an experience we did not have. If we add our own measurements in the future, they will be labelled as ours and kept separate from manufacturer data.
6. Corrections
If you find a value that does not match the manufacturer’s current document, send us the link. We re-check the document, then update the value, the access date shown next to the source, and the page’s “updated” date.