A couple of days ago, I noticed a small ridge on the sasame filter of my Hokujo teapot. I wondered if it was a small manufacturing defect I had never noticed or a crack. I pulled a bit with my nail and found out a small part of the filter had detached and easily came out.
I do not know how this happened. Preexisting small crack that slowly expanded? Mishandling on my part? Thermal shock? I will never really know, though I do not remember exerting any significant force on the filter, for instance while unplugging holes with a paper clip (which I incidentally did just before this happened).
Intuitively, I would assume sasame filters are more prone to damage than direct hole filters and ball filters. When I got my first teapots, I would have thought a sasame filter was better in use, but frankly I have found teapots with direct hole filters and ball filters to work fine, even with fukamushi. I really liked that teapot and used it very often, but I wonder it I should look for another one with a similar filter or if I am likely to experience the same thing again.
Any thoughts, experiences or recommendations?
Broken filter
i'd just chalk it up to bad luck. if you were careful with it, then i think there was probably a defect that lead to eventual failure.
also, i think it's more fragile than other kinds of filters. it's a large, thin, less-supported structure.
i don't have pots with sasame filters, but that's just because i don't like how they look.
also, i think it's more fragile than other kinds of filters. it's a large, thin, less-supported structure.
i don't have pots with sasame filters, but that's just because i don't like how they look.
Maybe it is a defective sasame filter. I have four or five sesame filtered kyusu that I use often and none have had this kind of issue. To clean out any clogged tea leaves I use a toothbrush, using a paper clip might have been too hard on the thin filter. Also, after each use I rinse with boiling water, and dab lightly with a soft cloth careful not to apply too much pressure on the filter. I have read of people drying with too much pressure and breaking the sasame filter. I especially like sasame filters for very fine needles like in fukamushi since they do not clog and pour really clean and fast. How long have you had the kyusu? Maybe you can contact vendor if it hasn’t been too long.
I think I was really gentle, but then again who knows. Toothbrush next time for me too...

I always heat the pot with boiling water, remove some water from the filter by shaking the teapot of hitting it against my hand, and air dry. Aside from unclogging filters, I basically never touch the inside of the pot.
I drink fukamushi from time to time (going through a bag right now), but I have never had any teapot clog. I end up with a small amount of leaf particles in my cup, but I don't mind at all. Maybe I have been lucky that the fukamushi senchas I have had (not that many) did not have ultra-fine leaves.
I bought it from a fellow forum member. I really like that teapot and use it almost every time I prepare tea for my partner and I, but the sasame filter was really not a reason for me using it. I guess I will continue using it for large-leaf teas, for which the hole in the filter should make no difference.
Since I started pouring back down the spout occasionally (easy to do when you are using a gooseneck kettle, but also easy from the tap), particularly doing a last rinse that way as I am cleaning the pot after a session, I haven't had any filters so clogged to require any more aggressive cleaning beyond an occasional rub with a finger tip or scrape with a fingernail, whether direct hole or sasame style filters.
Unfortunately, it crumbled a bit rather than break in one solid piece. The holes are very small, so I am not sure how I could attach anything without risk of further damage, especially since there is no way to access the filter from the other side (at least without special tools). If a repair is possible, it would require tools I do not have, and probably also skill I do not have.
Considering the time and potential expense I would have to dedicate to research a repair option, maybe I would be better off keeping it as is, using it for teas for which the hole is not a problem, and get another one. That way, I get to have my cake and eat it too...
It would be easy to place a round stainless steel mesh over the sasame filter, held down by two or four thin stainless steel wires bent to a looped shape. Otherwise, you risk leaf getting caught behind the filter and getting stuck there. I know it’s not aesthetically as refined and your introducing SS inside, but it’s functional.faj wrote: ↑Sun Oct 25, 2020 8:51 amUnfortunately, it crumbled a bit rather than break in one solid piece. The holes are very small, so I am not sure how I could attach anything without risk of further damage, especially since there is no way to access the filter from the other side (at least without special tools). If a repair is possible, it would require tools I do not have, and probably also skill I do not have.
Considering the time and potential expense I would have to dedicate to research a repair option, maybe I would be better off keeping it as is, using it for teas for which the hole is not a problem, and get another one. That way, I get to have my cake and eat it too...
I mentioned earlier in this thread that all of my teapots were doing an acceptable job with fukamushi. I was wondering if people paid attention to the filter only because they mind the bits that pass through the filter.
I have glass teapots that I use as pitchers 99% of the time, but once in a blue moon I use them to infuse tea. They have this stainless, spring-like filter with a little hook that grips the tip of the spout. I made fukamushi with one of these today. It was a total and utter disaster. It took at least a minute to pour the tea out, and that basically ruined the result.
So it seems the filter matters after all with fukamushi, but it so happen that the filters typically found in Japanese teapots, even those not specifically intended for fukamushi, happen to to a very decent job of not allowing much bits to go through, while still being able to pour quickly.
I have glass teapots that I use as pitchers 99% of the time, but once in a blue moon I use them to infuse tea. They have this stainless, spring-like filter with a little hook that grips the tip of the spout. I made fukamushi with one of these today. It was a total and utter disaster. It took at least a minute to pour the tea out, and that basically ruined the result.
So it seems the filter matters after all with fukamushi, but it so happen that the filters typically found in Japanese teapots, even those not specifically intended for fukamushi, happen to to a very decent job of not allowing much bits to go through, while still being able to pour quickly.
I am very picky about which filters I use for very fine needles since I’ve had too many situations where the pour was super slow after getting clogged up. Now, if available, I’ll use sasame filters for those very fine teas. I really enjoy a super fast pour with no clogging. Of course, with a slow careful pour other filters can work too, but too fast and they clog up ruining the session.