Takenaka Carpentry Tools Museum - Kobe
Not a design museum per se, but highly recommended
The Takenaka Carpentry Tools Museum in Kobe is a total dreamland for wood lovers 🙋🏻♀️. It has cross- and tangential-sections of trunks and you can sniff wood shavings to your heart’s content! It teaches you about wood, processing, tools, and carpentry techniques with many things to touch and try. The best is the table that has all sorts of carpentry joins without nails that you can play with. I spent half the day here and must say it’s one of my favorite museums that I’ve been to in all of Japan.
Planning
They had workshops (not sure if in English?), I wish I knew before, so please have a look on their website and book in advance (at least before 3pm the day before). https://en.dougukan.jp/
It’s near Shin-Kobe, and I found it convenient to do it when making my way to Arima Onsen via the ropeway.
They had a free audio guide which was very informative.