thinking of digging into 3D printing, can i just add a head to my CNC router?

tommylight post=227199 userid=17274Every 3D printer has a heated bed that is very good at drying fillament.
 

except mine i have not bought a bed heater yet. perhaps at some point, when i take up on the idea again. still have my PETG sealed, and my extruder, so it is not a loss yet, until i accidently break something...
current thought is to rough something out so i can play with the idea, and experiment with other ideas. the best part about a large CNC router table... room to experiment. my biggest hold-up, other than money, is space to really get around the machine. as it sits in the back of an old camper, and takes up nearly the whole back end, i only have one side of access.
planning on building a larger shop to work in, and will have room to really work on my machine, and more importantly, AROUND my machine.
but what i have learned here so far will not go to waste, as the idea is simply on hold.
looking forward to trying out my Arduino thermal PID, and how it "should" interact with LinuxCNC. i may even grab a Arduino later today and load it up, and connect it, just to see if everything works. i can easily throw a little potentiometer on the analog pins to test the temp reading, and some LEDs on the PWM outputs to check the PID responce. maybe even try that now...

~Travis

Arduino PID was an utter failure. nothing on LinuxCNC would respond to the Arduino PID... i would figure it out, but my LinuxCNC laptop was knocked off my lap by the dang cat, and broke the computer end of the USB cable, and knowing my luck, the USB port too...
so i am just back to what i know works, for a while... before i break something really important.

~Travis

i FINALLY have a semi-working temperature controller! not yet a PID, but i can connect an Arduino to my LinuxCNC, and read and set a temperature for two things (bed and extruder head) i used code from here: emergent.unpythonic.net/01198594294
i had to fix a few things to get it to work for me, but i can turn a potentiometer on an arduino and watch a pyvcp gauge move in relation!!! i am so happy now, i could just kiss something !
my limiting factor was getting it to communicate with LinuxCNC well, and that my copy of Debian Buster had a very old copy of the Arduino IDE. but now that it works, i have saved a reference copy, and will eventually put it up on my Github for later. now i just have to get the PID library working with it, and if it compiles after that, i suspect it will work with LinuxCNC still. then i can work on the real hardware, rather than just an arduino and a breadboard circuit.

3D printer project is BACK ON!
i will be sure and post a copy of my arduino and python code, when i am sure it works. that way others can find some way to abuse it always been a fan of freely available open-source code, if it can help somebody else in any way.

good to know though, that i can use most any filament in humidity, for testing reasons, and as long as i don't mind poor quality tests.
Still working on figuring out a heat-bed. they are expensive, and some look very poor quality. they have an adhesive back, so i assume i stick them to the back of the printing surface, and add a insulation layer to help hold it in place, and hold the heat better?

for reference, i will attach the rough "pid" code i made to test with. it isn't accurate, and is very erratic, but it communicates. the python script is set to run on python3, as that is what i have. may have to change for other needs. the arduino code seems to work on an Arduino Mega2560 (clone), and the python code works with the master branch of LinuxCNC.

~Travis
 

Short of tuning the PID to work with the heaters and thermistors i have, i have a fully working PID!!!
github.com/travis-farmer/linuxcnc/tree/m...dprinter/ard_3dp_PID

~Travis

andypugh wrote:

I don't think that you need an Arduino at all.

You can use the LinuxCNC HAL PID, a thermocouple and linuxcnc.org/docs/2.8/html/man/man9/max31855.9.html
 

ok... now you tell me... now that it works...

ok, how do i setup HAL PID for a thermocouple?
i don't recall how many PWNgens my Mesa 7i80 is configured with, looking for what i have on it now...

~Travis

i think i have SVST8_4 installed on my 7i80HD-16...
so plenty of PWMs

~Travis