Here's how to make a leather baseball with DAISO's 75mm foam core. You can download the free project plan from here:

Coffee and Craft: Original Project Plans
https://coffee-craft.net/leathercraft...

It requires Leathercraft CAD which is a free CAD software specifically designed for leathercraft pattern drawing. It has a lot of leather craft related features that none of those existing generic purpose CAD software have. At the same time, it’s very simple to use even for beginners or non-experienced CAD users. It runs on Windows OS and macOS.

Website: https://coffee-craft.net/en/
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