A 120mm Fan to HEPA Filter Adapter to remove printer fumes, remixed from MQ1991 work here and my work here.

MQ1991 model was good but after repeated replacement of the HEPA filter, the plastic taped screw holes began to degrade leading to the fumes escaping from the adapter. My cap adapter had problems when printing due to how I made it. I have redesigned the adapter in Inventor to contain captive m3 nuts so the screws don't degrade, and added chamfers to the cap so printing issues don't arise. I have uploaded the ipt files in case anyone would like to edit them.

The new model uses 4 captive m3 nuts in the filter holder, and 4 m3x20mm bolts to bolt down either the lid or the cap. To insert the captive nuts stop the print at layer 289 using a 0.2 layer height. I use the pause height gcode in Cura found in extensions/post processing/ modify gcode to stop the print at the correct layer.

I have also added some decals to the outside of the filter holder to help know which way the airflow should go when the filter cap is attached. I have reduced the height of the filter holder by 5mm and the height of the filter cap by 20mm which should conserve filament better than the previous models.

I would recommend to use this in combination with a carbon filter to remove nasty VOCs from the unfiltered air. I use this adapter here designed by JakesterDS after the HEPA filter. I change the HEPA filter every year and the carbon filter every 6 months. I do this based on the recommended service intervals for changing carbon filters in kitchen extractors.

You'll need:

• A high static pressure fan to overcome the HEPA filter and Carbon filter. I would recommend the Arctic P12 Max 120mm Fans available here. They have a slightly higher static pressure and air flow, similar life spans, and are cheaper when compared to a medium range extractor fan used in bathrooms, which makes them ideal for fume extraction.

• 86889 HEPA filters available here

• 4 m3 nuts and 4 m3x20mm bolts. The gap for the m3 nuts is 3.5mm deep, so locking nuts will not fit.

• For gaskets between the parts I used electric tape for smaller gaps and storm guard rubber strips for larger gaps (mainly between fans).

19/03/2024 V1.1: Reduced filter slot height from 20mm to 14mm due to incorrect taring of microcaliper (oops). Changed filter slot dimensions from 151mm x 101mm to 148mm x 100mm as the slot was too large and the filter was too loose.

20/03/2024 V1.2: Changed filter slot dimensions from 148 x 100mm to 150mm x 101mm as my initial measurements were more accurate than the documentation sizes. Added chamfers to bolt head hole on filter cap to stop stringing around those areas.