Has anyone figured out how to use the holes around the rear ventilation fan to mount something?
I can’t figure out if those are just holes or they’re meant for screws? If so, what kind of screws? The hole seems to be ~2.25mm to the extent my calipers can measure it.
I also wasn’t sure if there was anything important on the other side of the holes that a screw poking through could interfere with. I don’t think I can see the other side of the holes without disassembling the printer partially (the plastic housing around the fan / filter blocks it), which I’m not planning to do.
I may go with a magnetic mount like an example on the web [1] (and maybe add 3d printed pins to go in the holes just for alignment and a TPU gasket). But screws would be simpler.
For context: I’m interested in an exhaust hose. I’d probably add a fan to the other end of the hose to try to make negative pressure at least in the hose and maybe add a taped-at-the-top paper flap over the poop shoot (light enough that it can open at the bottom to let stuff out, but stiff enough that gravity + negative pressure will shut it). The case is probably quite leaky overall, though, so I don’t know if this will work. But worth a try and fun to design / print the parts.
I’m aware that if it does work, it could affect the enclosure temperature and printing results, but I’m pretty cautious about fumes (even for PLA / PETG), so I wanted to try. I may end up enclosing the whole thing eventually.
Oh, nice find. So they’re not threaded, but I could thread them with an M3 thread tap if I got one. Maybe I’ll go with pegs and magnets for now since I have those and no tap, and try the tap if I don’t get a good enough seal with a TPU gasket.
I’m not planning to reuse any of the designs I’ve seen because I want to hook it up to a standard US dryer vent hose (<$10) and put a high static pressure PC case fan at the other end (~$30) so I can exhaust it outdoors when in use (and bring the fan / hose in when not in use), rather than trying to filter it and exhaust it in the same room (as I think that expensive system does). Remains to be seen whether it will be able to keep negative pressure, though.
Thanks for pointing out the original source with instructions! I should have found that.
I ended up printing a standard dryer hose mount in PetG with snap in pegs to line up with the holes and places for magnets, a gasket-ish thing in TPU, and a mount for a case fan on the other end of the hose. The rings on the mounts are for thin rubber bands, with them I get a great seal on the dryer hose (better than I can get around the fan or the back of the printer).
It works reasonably well. I removed the charcoal filter in the chamber fan and taped a thin piece of paper over the chute in the back and the suction is enough to keep it flat. Especially with the chamber fan running, you can feel the airflow into the case at the vent at the back / door cracks. I think it was great for PLA, I measured almost no change in indoor air quality even on long prints (disclaimer: I do have a HEPA filter running in the same room, so PLA isn’t super toxic regardless). Not so much with TPU, I don’t know how much plastic that is turning into VOCs, but I still got a measurable amount of VOCs (via an Airthings monitor) in the room.
I can provide actual models if there is interest (but I’m not particularly interested in uploading them to a site / supporting them).
Hey, wondering if you would be willing to share the models, I would love to add this to my printer. Would also like to know how it has been working for you. Thanks!
While room filters such as the Winix may filter out most of the room contaminants eventually, it would be better to keep the contaminants out of the room that we breathe in.
Just be aware that the chamber fan, which these designs rely upon, is positively pathetic in its ability to move air, even without the flow being further damped by extra filters or long vent runs.
I don’t know a lot about fans or air flow but after I replaced an external HEPA contraption to a smaller internal one right above the original carbon filter, it seems to me the flow got a whole lot better. The obvious difference is In the former case, the HEPA adds resistance on the pressure side and in the latter it’s on the suction side. Does that make any sense?
