3D Printer Controller

[wickwire]

Hi everyone,

Ever since I got my 3D printer (CTC 3D Dual Extruder) around May 2015, I’ve been working out ways to remotely handle my print jobs.

I’ve managed to achieve my goal, so I’d like to share my current setup with the 3D Hubs community!

So as many other users out there, I’m using Octoprint running on a Cubietruck (embedded micro computer board) in order to operate the print jobs remotely. I’ve also added some webcams to the printer frame in order to be able to check on the print jobs and cancel them in case things start to go wrong.

Regarding Octoprint and setting it up on a micro computer board, there’s the OctoPi variant for the Raspberry Pi, but generically speaking, it should work also on other embedded boards and you can have a look in my blog for the steps I took while setting it up on mine:

http://wickwire2099.blogspot.pt/2015/06/cubietruck-and-ctc-dual-extruder-printer.html

http://wickwire2099.blogspot.pt/2015/06/cubietruck-and-ctc-dual-extruder.html

Next up, I thought about batch printing. Usually, for printing, you have to use some adherent on the bed, depending on the material you’re using - and 3D printing was quite an “on premises” operation for me with each print job, either applying some adherent like hairspray, or changing adhesive tape, etc.

So I found out about printing with glass - and more specifically, Sitall glass - which according to the manufacturer, would have great adhesion properties, wouldn’t require any adherents to stick and at a certain temperature while cooling off, the parts would just unstick and pop off the plate!

So I got one of those and started experimenting with it. A lot of talk online mentioned that the solution was non-working, or too expensive, etc.

At first, the pieces would stick in the beginning of the job and then mid-print, they’d pop off. With the help of the 3D Hubs community, I figured out that the heated plate on my printer wasn’t actually reaching the actual 110ºC/115ºC temperature that Sitall needs for ABS to stick, so after replacing the thermistor (thermal sensor) on my printer’s heat bed, the prints started to stick as advertised!

I got positive results with PLA, ABS and even TPE!

And also as advertised, I also had the parts unstick and pop off from the plate on their own, once the glass temperature cooled down below 90ºC! So I’ve been using Sitall for a few months now and I’m really really pleased with it!

http://wickwire2099.blogspot.pt/2015/12/ctc-3d-and-sitall.html

Going back to the unattended, batch printing plan: since the parts popped off automatically, I could use Octoprint’s manual controls and the Webcams just to push the print parts out of the heat bed and start consecutive prints - yes, I know, it’s criminal of me to use the extruder head to push stuff out of the way like that, calibration and overall damage came to mind but guess what, the printer is brilliant, keeps on printing just fine and you wouldn’t believe the amount of fun I’ve had just remotely pushing stuff away on the webcams - it’s like a tradition at work during lunch break whenever I have a print going!

Finally, I thought about adding some LED lighs to the printer frame because the webcams would be useless under low lighting, and that gave me an idea to also control the printer in terms of power.

So I used a micro-controller board to operate two solid state relays, where one relay controls the LED strips I got from IKEA and the other relay controls the printer power cord.

I used the MQTT messaging protocol in order to control the micro-controller over the internet and developed a basic web application with two buttons, enabling me to view the webcam streams and turn the lights and even the printer on/off…!

http://www.esp8266.com/viewtopic.php?f=152&t=8708

So that’s it guys, I’m sure the whole project would still have room for improvements but as it’s working for me, I’m just sharing with everyone!

Also, if you think this project is cool, it’s submitted in a contest currently under way at the last URL, so vote for it if you feel like it!

[Mat_Withers]

Hi Wickwire

Thanks for the write up - you’ve done a lot of things that I’ve been thinking about - nice job !

Can you give a bit more information about replacing the heated bed thermistor - what part did you use ? and was it a pretty easy soldering job ? My current one is about 15C out so would love it fix it at some point.

I’ve also noticed (using an IR thermometer) that the temperature over the surface of the print bed varies but about 7 - 8C (colder at the edges) but I can’t see there’s much you can do about that.

I’ve been printing on glass for a while with great results, I’ve been looking at replacing the aluminium bed with a sheet of glass with the heater board on the back. I need to find someone local to me that can drill and countersink a glass sheet fairly cheaply to try this out.

Mat

[wickwire]

Hi Mat, yes the soldering job was quite easy, I took some screenshots of the heatbed documented everything on my blog:

http://wickwire2099.blogspot.pt/2015/12/ctc-3d-and-sitall.html

And yes, the temperature does vary a bit around the edges as it would be expected, however it shouldn’t be a problem for large surfaced PLA prints, might be more of a challenge on ABS.

I’ve been trying to print a Cubieboard case using ABS and I get some slight warping around the edges, however I believe it can be fixed by properly isolating the printer enclosure. I’ve isolated the enclosure already and will try it out again as soon as possible.

The glass still manages to keep the part quite stuck, so for me, changing the thermistor that came with the bed (56 KOhm) with a new one (100 KOhm) really did the trick!

Sitall glass is quite think (at least the one I got) and not that cheap, but once I understood how to use it, I don’t think I’ll be going back. They didn’t have the exact measurements for my heatbed at the time, so I decided to buy a slightly narrower glass plate and it has been working like a charm. I’m on my way to a second printer, a prusa i3 variant, so I’ll definitely be getting a sitall plate for that one and when I get to it, I’ll get another one just the correct size for my CTC printer!

[Blizzard]

Hey, sounds like a cool project. Wondering if it might have the capability to control multiple printers remotely? eg 6 printers, all in one location, but controlled by the setup you mentioned?