3D Printing


#81

good point … what about ventilation?

I’ve read a story that most 3d printers are open, because of a patent thingy, So how do you ventilate… just open a window or did you build a lorawan air quality 3d printer sensor that triggers an air filter ventilation thing … :sunglasses:


#82

[OT, move to 3D printing thread?]

Buy quality PLA, avoid ABS and ventilation is not too much of an issue. For ABS (and nasty cheap PLA) you want adequate ventilation. However, avoid draft as prints must cool evenly to avoid distortion and lifting from the bed during printing. I heard you should look for SLA/DLP resin printers if you want really nasty smells :wink:


(Duineuk) #83

If you want to have some fun with the Safety Police, post on any of the 3DP forums and ask innocently about air quality and nanoparticles :slight_smile:

There’s a health concern worth considering, I guess; you are spraying hot polymers around with associated fumes and micro debris. For me personally, I don’t consider it a serious risk, and I print at one end of my lounge.

There’s a whole culture around hacking the ikea LACK table into a printer enclosure should you be concerned.

As @kersing says, you need one for ABS as constant temp is important to avoid warping. I print PLA, PETG and TPU and have no problems with an open frame.


#84

PLA, PETG and TPU, SLA/DLP avoid ABS … got it :wink:

hello world of 3d printing… have to read and google more coming weeks


(Duineuk) #85

SLA/DLP print small models at very high resolution. They are also expensive in consumables, messy and smelly. For the kind of thing we do in electronics, there’s really no need for them - FDM printers are fine :slight_smile:


#86

more or less related


(Duineuk) #87

Finally finished my gateway and enclosure. Really pleased with it - perfect combination of electronics assembly, design, 3D printing and engineering :slight_smile:

STLs and notes here: https://www.thingiverse.com/thing:2825049

Thanks again to @Amedee for the inspiration!

![IMG_2441|375x500]
![IMG_2444|375x500]
(upload://dArvSj8Wps3UhhvSO4FxCnD8DxV.JPG)


#88

Reading up on this thread made me think. Do I really need a 3D printer? Looking around my worktable gave me a clue. So many unboxed projects.

As tinkering is the hobby decided on a Anet A6 diy build.


Waiting for delivery in couple a days to start the build.


(Allen) #89

I’ve been working on an air quality monitor for the local city. The first generation units were 3D printed, stuffed into a PVC pipe, then hung on the rail next to EPA monitors to characterize sensor performance. Those are using WiFi to send data to a local LTE modem to be recorded and presented on a public website.

I’m now working on the 2nd generation units using the HelTec ESP32/LoRa boards I discovered while reading these forums. Before developing the outdoor version, I wanted to make an indoor unit that I could use for software development and demonstration.

Here’s what the enclosure looks like modeled up in SketchUp:

Some action shots of the assembled unit. These were printed on a Prusa Mk2 (Prusa printers are seriously top-rate, you get what you pay for here) using Atomic Sapphire Blue PETG Pro.


The unit has a PM sensor, O3 sensor (which also provides temp and humidity), along with a GPS module. This is all sent to a ThingsBoard deployment on a cheap VM in Azure for a realtime display of position and sensor data:


(Allen) #90

While working through a LoRaWAN deployment for the city, I thought it would be helpful to be able to map out coverage, so I also wanted to build a quick TTNMapper device:



That’s another HelTec board (same as the previous post), another cheap GPS module, and a 270mAh LiPo battery that will run the thing for all of maybe 30 minutes. Zero effort has been made to power optimize this thing, but the results have turned out pretty solid for the limited use it’s seen thus far.


#91

I have been looking at the SPEC sensors for air quality monitoring, how well do they perform in your experience?


(Allen) #92

Our first gen units are using PLANTOWER PMS5003 PM sensors along with a Winsen MQ131 Ozone sensor. The PLANTOWER PM sensors have performed admirably through the course of a Michigan winter and the data generated from them aligns nicely with the federal reference instruments that they are positioned next to. I wish I could say the same for the MQ131 - that sensor is nearly useless, it uses variable voltage output that, once settled, never changes at all. I could have saved myself some money by replacing it with a resister for all the good it has done.

I’ve spoken to Spec directly about their sensor line. They have been in the gas sampling business for a while and are just now selling sensors for IoT use. They have datasheets in English (!) and distribution through actual resellers like DigiKey, all of which I wasn’t getting from Winsen. Further, they offer it in a factory-calibrated package which shoots out digital readings over a UART connection, making them dead-simple to integrate.

So, thus far I LOVE THEM, however - they have not been placed in the field, and I have no idea (yet) how well they actually perform, so I’ll withhold judgement until I see the data.

One substantial drawback is the price - at $75, that one module clocks in at 3x the price of the rest of the package combined, and has resulted in the BOM going from ~$30 to ~$100 which is a little annoying.


(Pixelchain) #93

Just purchased today this duct tape (textil based) that seems to be very good if you print with cold bed.

Still testing but it looks promising,


(Duineuk) #94

I need a heated bed for PETG, and it helps prevent warping with PLA. That said, I used the basic blue painters’ tape on my old Printrbot (no heat) and it works well enough,


(Pixelchain) #95

The second printer I have doesn’t have a heated bed (it is a small one that I keep on my desk).

The problem I have with painter’s tape is that it gets broken really easy and sometimes, for large objects, the tape goes off with the objects. This one is very resistant and it sticks fairly well, but the black one leaves a little bit of markings on the object.

So, I will go back to blue tape :slight_smile:


(Amedee) #96

You probably already know know that, but the 3M blue tape is available in wider sizes (55, 70, 120… mm).
Wide ones are easier to apply (less lanes to cover the plate), and offer globally a better adhesion (probability that an object lift an edge of the tape is smaller)


(Ryan Walmsley) #97

I’ve found the best solution is to use a build surface. I didn’t like tape so have used a mix of Buildtak and similar. I currently use a cheap Chinese one which works pretty well.

One sheet of a plastic with a texture which helps with sticking. Usually only need to print PLA at around 40 degree heated bed.

PEI Is believed by most to be the best however I’ve not had the best results with it but need to try again.


(Pixelchain) #98

I was also considering it…
Did you try Buildtak w/o heating the bed at all?


(Ryan Walmsley) #99

I think I have and it worked. However I find it slightly easier to then remove the part if the bed’s been a bit warm when printing.


(Amedee) #100

I mainly use the backside of the Buildtak…

:joy: