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Toolbox.
Small tools I built because I needed them on real projects, then cleaned up so anyone can use them. They run entirely on your own device. Nothing is uploaded, nothing is tracked, and they keep working when the site has no signal.
Crane Lift Calculator
Sling tension on the BS 7121 two-leg rule, ground bearing pressure and pad size, permissible wind speed, required boom length and headroom. With live diagrams and a printable record sheet.
AR Viewer
Turn a Revit FBX export into a USDZ file and see the model at real size in AR on an iPhone or iPad. The conversion runs in your browser, so the model never leaves your device.
More on the way
Duct and pipe sizing with a velocity check, drainage fixture units to pipe size, an MEP unit converter, and an ISO 19650 file name builder. Each one gets published when I trust the numbers, not before.
How I treat these. Every tool says which standard it follows and what it deliberately leaves out, on the tool's own page. None of them replace a competent person, a manufacturer's chart, or a signed calculation. If you find something wrong, tell me and I will fix it and say what changed. If there is a tool you want, ask, and it might be next.