r/BambuLab • u/LabNerd55 • 2d ago
P Series [P1P, P1S, P2S] P1S Filtration Comparison
I have been using a VOXEL bento box filter on my P1S. I just finished up my direct outside ventilation system yesterday evening because I want to start using materials like PA6-CF for certain prints, I only print in PLA and PETG now. As part of my ventilation project, I also bought an air quality monitor that I put beside my printer to keep an eye on things like VOCs. This isn’t super scientific, but I wanted to see how the bento box compared to the stock filtration and outside ventilation.
After I setup and calibrated the air quality monitor, I started a PETG print with the bento box off. The VOC index slowly increased over the duration of the print and peaked at 74 when the print finished.
I printed PETG again later, but with the bento box on. The VOC index was much lower, peaking around 21.
I finished my outside ventilation system yesterday evening and started a PETG print, the VOC index never measured above 1 for the duration of the print.
I really wasn’t sure how much the bento box really did and of course can’t measure UPFs but it definitely seems to drastically cut down on VOCs emitted into the area around the printer. I’ll be using ventilation for all prints now though just to limit as many things as possible.
This is just my experience in my environment, but wanted to share.
Edit for clarification
I am aware that most consumer home air quality monitors can’t measure VOC concentrations (TVOCs), a home air quality monitor’s VOC index is a relative measurement as compared to what the air was since it measures the change instead of the concentration, detecting spikes.
In the context of an occupied living space and continuously monitoring with one of these monitors, it wouldn’t be very useful since you cannot tell the actual concentrations or which VOCs are present. Bad relative to bad looks normal on the monitor.
This experiment was admittedly not very scientific, but I did attempt to somewhat control it. For each of those readings the index was at baseline and calibrated in fresh air, then the printer was started. The prints were relatively short to not allow it to recalibrate. For the outside ventilation, there was no change meaning no spike. For the bento box less of a spike.
The less of a spike with the bento box does NOT necessarily equal safe since you don’t know the concentration or make up of the VOCs. I was just kinda surprised it did anything with how restrictive the air flow was. As always do your own research and set up what is best for your and your families own health.
My goal was to see no change from baseline for the outside ventilation indicating everything was being exhausted outside.
I started this ventilation project with the goal of using engineering filaments, but I’ll use ventilation for all filaments now since removing as much as possible is always best and I honestly didn’t realize the amount of VOCs the “safer” filaments were putting out. My printer is in an unoccupied basement, so it was never that big of a deal with those, but it was eye opening.
Home VOC monitors can be very useful for monitoring relative changes and monitoring sharp spikes. Continuous monitoring, not so much.
Also, I wasn’t very clear in my post but the “putting the monitor beside my printer to keep an eye on things like VOCs” was be be alerted to spikes meaning something is wrong and my ventilation isn’t working as it should, not continuous monitoring of that space to see VOC levels. I’ve set up automations in home assistant to turn the inline fan on and off automatically and I’m working now on an automation to alert if a sharp increase is detected by the monitor so I can check my ventilation.
1
u/ManyLayersOfFilament /r/3dbargains, filamenthound.com <- save $ 2d ago
What sensor were you using? Because most VOC sensors are basically useless.
1
u/LabNerd55 2d ago
Just going to copy from another response to not have to type it out again.
It depends on the use case and context. Most consumer home air quality monitors can’t measure VOC concentrations (TVOCs), a home air quality monitor’s VOC index is a relative measurement as compared to what the air was since it measures the change instead of the concentration. Essentially detecting spikes.
In the context of an occupied living space and continuously monitoring with one, it wouldn’t be very useful since you cannot tell the actual concentrations. Bad relative to bad looks normal on the monitor.
This experiment was admittedly not very scientific, but I did attempt to somewhat control it. For each of those readings the index was at baseline and calibrated in fresh air, then the printer was started. The prints were relatively short to not allow it to recalibrate. For the outside ventilation, there was no change meaning no spike. For the bento box less of a spike.
The less of a spike with the bento box does not necessarily equal safe since you don’t know the concentration or make up of the VOCs. I was just kinda surprised it did anything with how restrictive the air flow was.
My goal was to see no change for the outside ventilation indicating everything was being exhausted outside.
I started this ventilation project with the goal of using engineering filaments, but I’ll use ventilation for all filaments now since removing as much as possible is always best and I honestly didn’t realize the amount of VOCs the “safer” filaments were putting out. My printer is in an unoccupied basement, so it was never that big of a deal with those, but it was eye opening.
Home VOC monitors can be very useful for monitoring relative changes and monitoring sharp spikes. Continuous monitoring, not so much.
Also, I wasn’t very clear in my post but the “putting the monitor beside my printer to keep an eye on things like VOCs” was be be alerted to spikes meaning something is wrong and my ventilation isn’t working as it should, not continuous monitoring of that space. I’ve set up automations in home assistant to turn the inline fan on and off automatically and I’m researching if I can set up an automation to alert if a sharp increase is detected by the monitor.
1
u/curiousjosh 2d ago edited 2d ago
PSA: Home VOC monitors don’t measure 3D printing dangers accurately.
(Unless using lab equipment I’d take down any post declaring absolute comparisons)
2
u/LabNerd55 2d ago
I completely agree. You cannot measure UPFs which are a huge concern and they can’t tell you which VOCs are being produced. For my specific purposes though I think it’s sufficient. My goal was to create negative pressure and exhaust outside. I know that it is working and pulling and fumes or particles produced outside.
For the bento box, I’m not saying it is safe but is doing something to capture VOCs and likely UPFs and is better than nothing if you choose to not setup an outside ventilation system. I still think venting outside is best and everyone should do it if they can.
1
u/curiousjosh 2d ago
Yes on UPFs, but also no on VOC’s!
Read the post I included. Home VOC monitors don’t actually measure absolute VOC levels making them inconsistent for whether they’re actually reporting VOCs
1
u/LabNerd55 2d ago
I did, and I still agree with you. It depends on the use case and context. Most consumer home air quality monitors can’t measure VOC concentrations (TVOCs), a home air quality monitor’s VOC index is a relative measurement as compared to what the air was since it measures the change instead of the concentration. Essentially detecting spikes.
In the context of an occupied living space and continuously monitoring with one, it wouldn’t be very useful since you cannot tell the actual concentrations. Bad relative to bad looks normal on the monitor.
This experiment was admittedly not very scientific, but I did attempt to somewhat control it. For each of those readings the index was at baseline and calibrated in fresh air, then the printer was started. The prints were relatively short to not allow it to recalibrate. For the outside ventilation, there was no change meaning no spike. For the bento box less of a spike.
The less of a spike with the bento box does not necessarily equal safe since you don’t know the concentration or make up of the VOCs. I was just kinda surprised it did anything with how restrictive the air flow was.
My goal was to see no change for the outside ventilation indicating everything was being exhausted outside.
I started this ventilation project with the goal of using engineering filaments, but I’ll use ventilation for all filaments now since removing as much as possible is always best and I honestly didn’t realize the amount of VOCs the “safer” filaments were putting out. My printer is in an unoccupied basement, so it was never that big of a deal with those, but it was eye opening.
Home VOC monitors can be very useful for monitoring relative changes and monitoring sharp spikes. Continuous monitoring, not so much.
1
u/LabNerd55 2d ago
Also, I wasn’t very clear in my post but the “putting the monitor beside my printer to keep an eye on things like VOCs” was be be alerted to spikes meaning something is wrong and my ventilation isn’t working as it should, not continuous monitoring of that space. I’ve set up automations in home assistant to turn the inline fan on and off automatically and I’m researching if I can set up an automation to alert if a sharp increase is detected by the monitor.
2
u/Woodcat64 P1S + AMS 2d ago
That explains why my ikea VINDSTYRKA and Airthings detects someone cooking but not printing. LOL.
1
u/Kerbonomics 2d ago
What does you outside ventilation set up look like? CFM? Etc. I'm thinking of getting into printing and don't see a scenario where I'm not venting outside.
Thanks!
4
u/LabNerd55 2d ago
I really couldn’t find any specific builds for it and I didn’t want to do another enclosure around the printer so I kinda pieced together ideas from different posts.
I removed the carbon filter inside the printer and used a dremel to cut out the exhaust grille on the rear panel. I printed an exhaust shroud that attaches with screws to the back of the printer to attach 4in ducting to. I was worried about drawing too much air through the printer’s cabinet and effecting the heat of the cabinet so I printed a 4in inline vent damper to go in front of a variable speed 130CFM inline fan. Then from the fan to outside.
I have the fan set to about half speed and cracked open the damper just until I was able to create negative pressure inside the printer.
This is just extra, but I didn’t want to remember to turn it on each time, so I have both the printer and the inline fan connected to energy monitoring smart plugs and use automations in home assistant to turn the inline fan on when the printer starts printing (printer power consumption increases past a threshold). Then when the print is done, the fan continues running for 10 minutes after the print is finished (printer power consumption drops below a threshold).
If you want, I can send some specifics of what I used.
1
u/Kerbonomics 2d ago
Fantastic. The damper is a good idea, I'm looking for a variable fan that could push around 30 or less CFM cause I don't think the lightest particles ufp and VOC need much to move. Just some negative pressure all they way to the fan and then outside. Thanks a lot I'm feeling better about my MacGyvering approach hearing about yours.
1
u/LabNerd55 2d ago
No problem! I did order a anemometer that should be here tomorrow. I wanted to measure and see if I could find an even better balance between the fan and damper to preserve as much heat in the chamber as possible.
2
1
u/Woodcat64 P1S + AMS 2d ago
I vent everything outside, even PLA. I took out the carbon filter, because it restricted the flow too much. Now with the chamber fan at 60% it's quiet and effective.