BedMesh both COLD & HOT show too great of range tolerance?
Hello All-
After much trouble of sorting out a bad MCU board, I'm going through the paces of commissioning and tweaking. While creating my BED_MESH readings & calibrations I noticed that my textured bed on my RatRig VCore 3 shows quite a large mound or distance above the level plane. Should I be concerned about this? The variance levels to me look too far above the level plane to be usable...what can or should I do to correct this? 2 screenshots with all the numbers showing for comparison.
20 Replies
Click the "scale gradient" in the bottom left so you can see just how bad it is. A total difference of less than a layer height is great
Thanks @TheTik. I'm not sure about the range, however:
Max [250.0, 190.0] 0.381 mm
Min [20.0, 20.0] 0.082 mm
Range 0.299 mm
BED_MESH_230 0.299
I thought the acceptable tolerance was .2 and I'm showing .299 which is approx 33% over tolerance?
And now I face yet another hardware challenge: My extruder & Hotend which previously worked just fine. no longer function under RATOS? I still have the test prints I did when the Duet 3 Mini 5+ was in my RatRig VCore 3, so I KNOW they work. That to me means: Voltage issue on the extruder, since the hot end heats and cools as it should...but the extruder cannot push out the melted filament. What should the voltage setting be on an E3D V6 hotend w/ BMG extruder? I looked around but cannot find a solid answer as to what the voltage should be reading. The extruder sounds like it is skipping or grinding to me.
Does the extruder spin? Does it spin the correct direction? Do you have the right exturder selected in the configurator?
Yes and yes. Extruder direction is correct and spins correctly. Again, this ALL worked on the last board, for the short life span of 15 mins, until the stepper drivers overheated on the MCU. My debug.zip I previously uploaded with printer.cfg shows the correct hotend (E3DV6) and extruder (BMG). Only thing that has changed since last use was the new MCU and Klipper/RatOS.
If you heat up the hotend, can you manually push filament through pretty easy?
No, That I cannot do. It seems to take a lot of force. I did pull apart the whole extruder assembly, checked that all out, removed the hot end and checked for blockage there. A little bit of melted filament (PETG) in the nozzle end , cleaned that out, replaced with brand new .04 nozzle ... same result. To me, it seems the extruder is not pushing the filament through and it's melting the filament but just sitting in the nozzle. Extruder works manually and without the hotend attached. I checked to make sure tension knob was not too tight or loose on extruder. I suspect undervoltage on extruder.
FYI I had hotend set at 245c for PETG and that should be enough to melt and flow PETG...
The fact you can't manually push the filament when the hotend is at temp points to the hotend being an issue. What did you do to verify it is actually at temp?
Good point. I was just going by the therm reading showing in the RatOS Dashboard. Screenshot attached. After pointing an infra red non contact laser unit at the hot end parts that are exposed (not hidden inside E3D Silicone sock) my temps seems WAY too low. Imagine that. Sooo how can my thermistor be that far off, when it also has less than 1 hour of use on it? I will see if I have a spare E3D hot end kit around, I think I do. Whether I have a new heater module for the hot end is the question. I have some for the Mosquito hot end I'd like to switch to, but not until I get the basics sorted out first.
what thermistor did you choose in the configurator? Is it connected to the mainboard or a toolhead board?
Hmmm....now that you mention it...I think the setup chose it for me. After looking at the Hotend section in RatOS, this is what I have: # WARNING. DO NOT EDIT THIS FILE.
To override settings from this file, you can copy and paste the relevant
sections into your printer.cfg and change it there.
Configurator Metadata
{
"type": "hotend",
"title": "E3D V6",
"thermistor": "ATC Semitec 104GT-2",
"flowType": "sf"
}
[extruder]
max_extrude_only_distance: 200
nozzle_diameter: 0.4
heater_pin: e_heater_pin
sensor_type: ATC Semitec 104GT-2
sensor_pin: e_sensor_pin
min_extrude_temp: 170
min_temp: 0
max_temp: 285
pressure_advance: 0.06
[firmware_retraction]
retract_length: 0.5
can you upload your debug.zip instead of pasting snippets
but in any case, the configurator should ask you what type of thermistor you have - maybe you overlooked it in the various menus?
Yes sir, coming your way. BTW- I'm looking at a DevilForge -one of my good friends is a Norwegian Viking and he makes CRAZY stuff like Japanese steel and Damascus steel pointy stuff. ; )
Is your thermistor labelled as to what type it is?
like on the cable or something
Hmmm. No idea It is whatever shipped with the RatRig VCore 3 kit back when I got it. It came with the E3D hotend and BMG extruder if that helps. I will pull it apart as soon as the hotend cools a bit more. It DEF gets very hot!
It came with the E3D hotend and BMG extruder if that helpsnope, I don't work for RatRig and have no idea what they shipped
Ok Hot end heater is def E3D: Says E3D 24V 30 watt, thermistor, no such luck, no codes or lettering. I pulled some new E3D hotend kits I had out and checked the thermistor values against the one I just pulled off the hotend on the printer: both read approx 100-100.5k at room temp (72f). Going to replace the therm out with a another new one anyway; something seems strange here.
I have both Platinum RTD PT100 & RTD 1000 therms ready to swap out. The PT1000 says it gives higher accuracy but the warning in the bag said make sure you do not need an amplifier circuit first, to prevent a fire!
you don't need one, you're fine
Also, just plug it into the thermistor port, don't get fancy and try and use the MAX chip on the octopus board
Agreed. I only need to swap out the therm with a short lead, so existing long wire looms right to therm port.