I use Vauen 180 x 9mm Charcoal Pipe Filters dr. Perl Junior. They fit nicely. Link to filters. a.co/d/htPBhGT Music from Uppbeat (free for Creators!): uppbeat.io/t/s... License code: CYQOIJSCTFOFGTXO
Interesting that 9mm filters are actually just under 8mm? What’s the thinnest wall you would risk? I want to convert my non-filtered pipes to filtered, but I don’t want to ruin the stem.
If I’m cutting a filter chamber of 8mm the thinnest is .75mm. Converting pipes is risky at times. I have convert about 50 pipes. Only broke four tenons. I was able to repair all four.