That feature list is pretty remarkable for the price. That wouldn’t even cover the wholesale pricing on the Sensirion particulate sensor I used in my DIY one…
I see there’s a Tuya based WiFi one, too… Iiiinteresting…
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Rats. Went looking for some information on them and it looks like there’s some sketchyness going on inside, so probably not actually measuring all that much in reality, sadly.:
The ikea monitors are a common thing to hack. I have seen some people installing esp32s inside to run esphome on them.
I have a couple of honeywell pm2.5 sensors. They have a little fan that blows at a constant rate across a gap. Inside the gap they have a laser diode and a phototransistor to measure the dip in intensity from PM4.0 particles. They then use some formula to guess pm1.0, pm2.5, and pm10.0. it is a good representation of dust and VOCs though. It can tell when we are cooking (especially bacon).
Yeah, my DIY one in my office is using the commonly used Sensirion SEN55 particulate sensor and SCD30 CO2/VOC sensor. It seems to generate meaningfully different but repeatable readings depending on whether I’m in the room and what I"m doing. Just being in there pushes CO2 up at a fairly constant rate to roughly the same value. Particulates go up any time I go in there and then settle slowly. VOCs also go up if I’m in there doing any assembly/testing work.
I think the particulate sensor is doing at least some level of inference for the different particulate sizes. From briefly looking at it, there’s nothing obvious like a linear correlation between the two, but I’ve also not spent any time trying to actually test it.
No Ikea here in NZ, unfortunately. There are a bunch of places parallel importing stuff from Ikea China but often it’s a pretty limited range. No motorized roller blinds, for instance, which is irritating.
I know a bloke who could mail stuff to you though…and weirdly we use the same plugs. Seriously let me know if you want something.
Back to the question though - what are we actually measuring when in comes to printing off-gas? Is it VOC, or some other nasty mustard gas?
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Sounds like a useful bloke to know 
I truly appreciate the offer and will keep that in mind.
I briefly looked into getting a couple of sets of the motorized blinds via a friend who lives in Sydney but the shipping made that prohibitive. An air quality sensor is a much friendlier size for shipping
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That is the same sensor I put on my dust filter in the garage. I honestly never look at it LOL. Maybe I should take it down from there and bring it in here instead lol
Yeah, that was ultimately the goal with my DIY sensor stack. Have it measure what’s going on when I’m working in the garage with the next steps being improving dust extraction, having a reminder to open the garage door to ventilate, that kind of thing. Next step for the unit itself was to design and print a box then order a few more of each, but it has been sitting in pieces on my desk for a year now. At least it’s running in that state!
The Apollo AIR-1 looks like a pretty good equivalent unit:
Unsurprisingly, it’s pretty similar to what I built, just with a screen on it. It has an option for a decent looking CO sensor which is pretty neat. CO is something I’m not really super bothered about, here. We’re pretty much 100% electricity as a household. Electric immersion hot water, heat pump heating/cooling, induction hob cooking, 2x EVs, completely got rid of the old lawnmower, switched the chainsaw to battery.
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Well maybe the filter wasn’t as bad as I thought it was. Still went with a fresh one before starting abs
The filters we’ve used in our soldering extractors get pretty manky looking immediately but seem to last pretty much forever. I don’t know how to realistically evaluate when they need to be changed. Presumably based on airflow and even the original one we’ve been using for nearly a decade still has tons of airflow…
As long as air is going through the filter at a reasonable rate, I wouldn’t worry about replacing them due to colour.
Yeah with these 2 cheap ass 4010 fans there isn’t a ton of air flow. Some better 4020 fans will be here Saturday and get swapped in. So for now I just went ahead and changed it.
I really do need a charcoal filter or two. My tertiary dust and fume extraction is a pair of 8" hydroponics fans - one in the “far” corner, and one midway - both go directly to outside. I leave the internal door to the house (next to my wife’s sewing area!) cracked a bit to keep airflow coming in the direction I need, and fumes, smells, dust and poisonous stuff head out in the direction I need.
My (what comes after tertiary?) solution is to open the garage door! It’s open except when I’m dealing with stuff that needs extracting. BackStory - I built the duct a long time before 3d printing - it’s developed from flat bits of 3mm MDF with real estate advertisement decoupage! 
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That just reminded me to check my sensors.
That’s the past week. The spike in particulates a few days ago is when I went in there and grabbed a box of stuff, so more material stirred up into the air but I wasn’t in there for long so no change in CO2 really.
The spike in CO2 yesterday evening was me being in there for ~15 minutes or so testing out a little panel-mount stepper motor controller that I want to use with my sphere turning jig. Was pretty much just sitting at the workbench wiring things up and testing the settings, didn’t really move anything around so much less of a spike in particulates.
Both of those are pretty minor, though. Going back a month I can see a situation where I was in the office for a couple of hours with the door closed to avoid cat-related interruptions and the CO2 peaked at around 1200ppm, which is well within the range where cognitive impairment is measurable. Particulates were also up to 30ug/m^3 due to the work that I was doing, even with the fume extractor running (or possibly even because of the fume extractor, given that it’s sitting on a carpeted floor). Pretty interesting!
We have an active ventilation with heat recuperation in every room, it’s changed the rooms’ climate massively.
I can sleep in one room with three of my kids in one small room in the winter and there will be only minor condensation on the windows when before half the window used to be wet.
Parts are looking great. Great photos of the process. Did you guys heat the powdered parts in an oven or something?
Love the printer bed pattern too.
Yeah. I have a large “toaster oven” that my (ex)Father in Law bought when he was powder coating some motor cycle parts a few years ago. He didn’t have the gun anymore but still had the oven thankfully lol.
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