I’m a little shocked that this would be case though. I tested with a sheet of tissue paper, and the fan sucked it in (is there another outlet?). Otherwise this would indicate that the static pressure differential reversed… which is physically impossible. A fan can recirculate air but still will always have some postive air flow. Going to look into this further to me it’s far more likely that the polarity was reversed in manufacturing… as others witness air blowing out of their units. I’ll test and get back here I suppose.
I’m not sure if that’s sufficient to exhaust abs fumes into your space?? Your not pulling out all the styrene
I just cut out the grille and printed out some vanes that I mounted over it instead (to redirect the flow to the side, since I have the printer installed close to a wall).
I mainly print PLA but it bothers me that I have to always have the top lid off the printer (noisy, and dust collects inside the printer) in order to keep the temperature inside reasonable for PLA not to droop on overhangs. I have been planning to make an extension between the top of the printer and the glass lid, with fans that suck hot air out while keeping the top glass in place. This will not look great, but it was the first plan.
I’m now looking at removing the stock chamber fan and instead put a centrifugal blower type fan in place of the vanes I just installed on the back. This type of fan should be able to overpower pressure differences much better than regular axial fans. I have some Delta BFB1012M on hand, will see how this works out. Hopefully it will be just enough (perhaps with the carbon filter removed) that I can keep the top lid stock, and in place.
Edit: Keep in mind that the stock chamber fan is a 24 volt part with rpm sensing. It may be easiest to keep it in place, and put a hall sensor or something on it for controlling the centrifugal blower. We’ll see if they can play nice.