Most of the firmware stuff is ironed out.
For now the heated bed is not working, we need to verify is the thermocouple is good or not.
Bill can you bring your laser thermometer it and check the extruder? I am certain it is not reaching the temperatures the system is reporting… It barely gets hot enough to melt PLA, but nothing more. I had it up to 260, but nearly impossible to push any filament through, and no bubbling like you’d expect with that hot of temp.
100k thermistor installed and set to 100k in firmware…
Also, the extruder seems to heat just a little too quickly…
thoughts?
The LCD will still corrupt every once in a while, I suspect it maybe from AC noise and/or a poor connection developing, I’ve noticed it when I move the display around.
Jim and I were poking and prodding today… Here’s what we found:
Heated Bed K-Type Thermocouple:
It turns out my $20 extech reads Ktype thermocouples. From the test points Bill & Julian found the my multi meter read the bed at 62 degrees, confirmed the reading at the board contacts too. So it’s either a bad connection somewhere on the board or a firmware problem,
Extruder Thermistor: - My probe indicates the extruder heats 30-50 degrees C lower than what the firmware is reporting. The offset seems non-linear, we loosely tried to fiddle with wires and trolley position but couldn’t trigger an inconsistent reading.
We tested the resistance of the installed thermistor vs the extra new one, Jim thought they seemed relative, so we suspect it’s just a calibration issue in firmware… I’ll investigate this further.
We need to check the firmware to make sure we are telling it the correct thermistor (for the hot end) as well as the pins. It’s (highly) possible they’re incorrect since they were for the endstops.
As for the K-type, Dave… I’m pretty sure the board has the converter onboard… but we can certaintly use one of each as a sanity check.
For cleaning the nozzle, I would recommend acrylic cement (weld-on #4) as it can dissolve pla. Acetone doesn’t work well. We have some in the combustibles box in the dirty room.
Is there a way in the software to get the measured voltage on the board instead of the converted temperature?
I would say that we have first to check if the measured voltage is correct regarding the temperature. How many thermistor do we have?
Before modifying the lookup table, we have to be sure that we get a proper voltage in input.
The PID autotune proposal was more to reduce the drift that we can have during operation. I will bring a few thermocouple and PT100 during this week and a DAC and/or a multimeter to make a comparative test on the gigabit.
I’ve reached out to Panucott and RE3D with our two current temp sensor issues… In the meantime the extruder could use a soaking if anyone has 20 minutes to tear it down!
The new Azteeg X3 shield is being shipped off to Roy/Panucatt, he is going to upgrade us to a Thermocouple shield… Sadly RE3D doesn’t mention this shield requirement anywhere… While our shield has the screw mounts, it doesn’t have the ICs for the thermocouple reading.
Someone has disassembled and is soaking the extruder… Can we also soak the barrel throat above it? There seemed to be some deposits in there too. Not certain its working yet tho, or its just goopy.
Once everything is reassembled we should run PID tuning. I taped the two thermistors together (it separated from the extruder) and comparing two multimeters, they read nearly identically. This is confirmation that the wiring/soldering is okay.
The nozzle should have a PTFE liner in it. It’s a simple matter to remove and replace that. 3mm OD, 2mm ID is pretty standard and I have plenty we can use.
Makes total sense that the RE3D version would not have that built it… NOT!
The Azteeg X3 board cover has been shipped off to Roy/Panucott, he is going to upgrade us to the Thermocouple compatible cover for free. Hopefully this will be back sometime next week. I also sent him some macarons from work as a thank you treat!
Just a heads up to everyone that the guy who owns the gigabot (John Helmsderfer) stopped by last night and was discussing a few things with us. He no longer wants to have it on loan and tentatively said he is looking at taking it back or giving us the option of purchasing it. None of this is set in stone and he said he wanted to see what we’ve done with it and then think about things (since he didn’t know if we were using it, or if we had modified it, etc) and he wants to give us some time to discuss it and think about it as well.
This will be discussed at the board meeting this coming monday so join us then if you want to be involved with these discussions.
While it has some nice capabilities, I feel like the Gigabot has been down or crippled or acting funny as much as up. (I’m not trying to blame anyone or make anyone feel bad) The Hive suffers from a lot of underutilized equipment because things break and don’t get fixed promptly. Rather than spend a lot of money on a very capable machine that needs a lot of upkeep, I’d almost rather spend money on equipment that is more reliable and can be kept operational more of the time, even if it is less fancy. I also do not use the 3D printers much so my opinion should be counted much less than those who routinely use the equipment when it is operational.
Jon, did you get money figures from him? If not, can you try to before the board meeting? If he wants $500 for that machine it will be a very different picture than if he wanted $5000 for it. Without some idea of how much the machine is worth to him this discussion is kind of shallow.
I agree with Dave on alot of this. The gigabot has been slowly going downhill with upkeep. while i like the build size, the quality is lower than average now i rather see us buy (or make) a more efficient / higher print quality model with a large build surface.
