I made a refillable activated carbon filter box for the Kobra S1 printer. The fabric used is from the original Activated Carbon filter bag that originally came with the printer. I just cut it and glued it in.

This box is a nice to have if you have a cheap supply of Activated carbon that you can swap out from time to time.

Recommendations: Have a thin rubber or silicone layer on the edges of the backside to make a proper seal. Layer lines are a good escape for air, but you want the air to go thru the filter and not around it.

Note: The box is slightly tapered on one side (as is the housing in the printer). Make sure to not force it in the wrong way.

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