I’m planning to add a small external exhaust fan to my setup, connected to a tube that vents fumes outside.
The goal is not to create strong airflow, but just a slight negative pressure so that no smells escape into the room.
Before I start building this, I wanted to ask:
Is there any way to have the P2S control an external fan directly?
For example, using a signal or port that can switch the fan on/off during printing?
If not, has anyone here built a similar setup?
I’d love to hear how you powered or triggered the fan, and whether you synchronized it with the printer’s operations.
I’d be grateful for any advice, experiences, or recommended solutions!
There really isn’t a way to control an external device from the printer. A while back they were beta testing a proto board that connected to a P1P for controlling external devices, but given what I’ve seen, that must of died off right after it started.
My personal setup I use smart plugs and Home Assistant to control the on/off state. This lets me have the ability to turn on/off things like my air purifier, bento box, external vent fan, and printers themselves. I used to have HA automations setup to be smart about when to turn things on/off, but over time I found it was just easier to toggle what I needed when I needed it. Even with all of this lock down shenanigans, you still have access to printer status, so you can still use those states to automate things like turning fans on and off.
The P2S has a second fan control port on the main board, so yes you can connect a fan, 4 pin type that the printer can control via the software.
I have been working on my own exhaust fan for this, V2 is about to be launched on makerworld tonight or tomorrow. It sucks air from inside the printer and pushes it out the bottom left air duct.
The second, left side fan is controllable in cooling mode only though. So PLA only, for other materials it is auto control by the printer.
The problem il that if you “push” the air from the inside, no matter what filter you use, smell is gonna flow outside, due to the fact that the case is not airtight… my idea is to have the fan outside pulling the air, so that no fumes coud escape from the printer. But the controllable fan is a very interesting idea, thank you!
Can you share ? I made my own too but you can select between circulation and exhaust. Still far from finish tho, but I guess I’ll check the one from bambu first before finishing this one.
I see the instructions, but currently the instructions say “the mole will be released… stay tuned”.
I’ve considered an inkbird digital sensor. It has 2 110 plugs, and an option for WiFi connectivity. It would be as simple as plugging the external fan to it. It would be GREAT to have inkbird capabilities all from the printer controller to include the ability to monitor and change settings through Studio and Handy. And be able to use the “clear the chamber” option.
I have a little controller coming I bought on AliExpress. It is manual but provided you have a 4 poll case fan you just plug it into the back of the controller and put a 5.5mm 12v plug in the other side. You can manually adjust the speed from 0-100%.
I ordered the exhaust fan from the Chinese store (friend did it) as I do not want to wait but since I have a second exhaust fan near the exit of my house to move air, as static pressure will be a problem, I have a made little device that will trigger on the output of the P2S and activate the other exhaust fan.
I think bambu Labs really messed up when they created the p2s without a internal heater. Unfortunately their newest accessory the fan on the rear with the panel only evacuates the vocs upon completion of print unfortunately the device is not airtight.
SOLUTIONS
For me the only feasible concept for not having a smelling room of ABS or ASA or whatever you are printing is to build an external tent that goes outside the unit with a fan which would be pulling the air around the unit outside. I was looking at some cheap tents for a $30 on Amazon that would fit on top of the p2s and cover it. Modify it cut the bottom off so I can just set it right on top of it and then turn the fan on. The problem now with their add-on solution even if you ran the fan the whole time you’re going to suck all the heat out of the unit and cause warping.
I am looking to do the same thing as you did.. I read somewhere that the board used for the external exhaust fan is 24vdc so I bought a 24vdc relay just need to know what the pin out is or what pins you used?
Any chance you could let me know which pins you used to do this?
Hi, I was GOING to do this, but I never actually followed through on it. If you ever do, let me know! I got tied up in other projects and just bought a small external fan with a speed control instead, that is hooked up to a smart switch so I can turn it on/off remotely for now.
Thanks for the reply, I am going to attempt it this weekend.. If it is successful, I will let you know how I accomplished it. Thanks again for the reply!
This is what I did, I used the exhaust fan kit and a commercial HEPA/carbon filter. It takes air from the poop shoot through the fan and then the filter back into the other air inlet. The fan can be controlled from the printers control panel. Been working fine since the end of February with PETG and ABS…
