New 茶碗: Immerse in lukewarm water for 30m, dry naturally; repeat for 1 week.
楽: Immerse in lukewarm water a few minutes before use; but make sure not to keep it in water too long!
After use: Dry for 1 week before putting back into box
To close small holes: boil with rice water for 20m, wash and dry naturally.
Types
筒茶碗(つつじゃわん)
There are also 半筒, which are handled like normal 茶碗.
利休 owned two 筒茶碗:
One made by Chōjiro four months before his suicide called 背高黒(せい たか くろ), which is a bit of a simple name (meaning *tall, black*). It looks a lot like the one I made, actually.
The other one is a Korean 狂言袴(きょうげんばかま)one called 引木の鞘(ひきぎ の さや)
These 茶碗 are used in 筒茶碗絞り茶巾(つつじゃわん しぼりじゃきん) 点前, which is performed in the cold winter. The shape of the 筒茶碗 preserves warmth, and the handling of the 茶碗, too, gives a sense of warmth.