Attached is an XML file with the thread definitions for creating internal STI (Helicoil) threads in models. There is no external thread support. This allows the creation of STI tapped holes, modeled and cosmetic, using the hole command, and creation of threads (modeled and cosmetic) on internal cylindrical surfaces. It includes thread data for coarse and fine STI threads from 0.073 (#1) to 1.5 (1 1/2) This was created and validated on Windows 10 and also tested on Windows 11 on the latest build of Fusion 360. However, not all thread sizes and drawing callouts were tested.
Traceability: All thread data was collected from a chart provided by Noble Aerospace Private Limited. You can find the link to the thread table here (http://www.noblefix.com/helicoil/HeliCoil-Tapping-Chart.html).
Methodology: Major diameters specified in the XML file are exactly as listed on the chart. Pitch diameters and minor diameters are averages of the minimum and maximum values for each thread specification listed. Tap drill size is the nearest drill in fractional inch size (1/64" minimum resolution) unless no fractional inch drill fell within tolerance. In that case, the drill diameter is to the nearest 0.1mm drill size.
Improvements: If any errors are noticed, please post a comment/reply on this forum thread. I want this file to be helpful to as many people as could use it. Thank you.
