Stability of Chemex Filter

Question

When I am brewing with my Chemex, most always the filter begins to drag down along the inside, and I always have to use my fingers to pull it back and re-balance the filter. I have tried regular Grocery Store filters (don't remember the brand name), and now I am using Chemex brand filters. Am I doing something wrong?

I have also tried mimicking techniques I see online, they bring up the issue of the filter insulating the Chemex and not allowing open flow; however I have never seen anyone address the issue I face. I would also be willing to change to a Chemex-adjacent piece if it would mean avoiding this issue.

Answer 1

This is a common problem I experience with my Chemex as well. My advice is as follows:

1. Pre-wet your Chemex (brand) filter while it's in the Chemex. While doing this make sure it's flat against the Chemex walls, this helps to create a "seal" that prevents the filter from falling. Be careful not to push it into the spout during this process.
2. I usually stir my pour-overs during the bloom, if you push too harshly down on the coffee during this step, it will also drag the filter down as well.
3. Check down the spout throughout the brew. If you can see a gap you're probably okay. If not you can lift up a bit to reset the filter.

The comment is correct as well, ensure the 3-ply part of the filter is over the spout.

If all this doesn't work, I've also seen Ray from melodrip fold the filters over the sides of the Chemex, to help keep it from falling. Be careful to not block off the spout while doing this as well.

Answer 2

I wonder if you are using the correct filter for your particular Chemex. On their website that there are basically three styles; halfmoon, circle and square.

https://www.chemexcoffeemaker.com/filters.html

One of these looks to be very narrow and if used in the classic style brewer may cause what you are experiencing.