Time4Tea wrote:Oy, who knew drinking tea would be so complicated!
It's not just complicated, it is a solemn responsibility!

(The word "oy" seems to be infiltrating TeaChat lately. I think
Victoria's Own was the instigator.)
As for cleaning the obi-ami screen, so far I haven't and it looks fine. I have probably brewed a hundred sessions in this pot so far. After brewing tea, I rinse it thoroughly with a full stream of tap water, direct some water into the spout, fill it with boiling water (often twice just to make sure it is really hot), let it sit for 5 minutes or so, drain the water leaving the empty pot still hot, use a paper towel to dry the inside as best I can including the screen, maybe twist the paper towel up and poke it into the spout, leave the lid off for at least 12 hours, and (best) place it spout-down in a mug.
Still, after reading Chip's speculation about what is growing behind the obi-ami, I am a little freaked. Oh, well, it hasn't killed me yet, and (more important) it doesn't seem to be hurting the taste of my sencha.
If there is something back there, I suspect that the best cure would be to brew a nice pot of sencha. Even if it doesn't kill the creepy crawlies, at least it will make me feel better!
And -- as Chip mentioned -- stronger cleaning measures, such as vinegar, can be employed in the case of a glazed kyūsu.
Mary R-
Dang that is a beautiful post about the filters! Thanks.