Most of my shop made piano tools are small, like cutters, wrenches, tuning hammers, letter stamps, and punches and dies, most of which are special items that can't be readily purchased from catalogs but which differ only in details of profile, size or font from ones that can.
Others are special fixtures and simple tools with slight improvements to devices seen in most shops. The first of these were for fitting new replacement hammers - I had been dissatisfied with the tools I had trained with, and designed mine to avoid their shortcomings in order to improve both the efficiency of the process and consistency of the results. The completed tools accommodate a wider range of parts and also make regulation simpler and more durable than I had been able to achieve with either stock parts or other tools.
I continue to try to expand the capabilities of my shop, and my small set of metalworking machines makes it possible to create useful tools that are both precise and long lasting.