Taz 6 temperature calibration

I apologize if this has been covered. I searched the board but the search capabilities are pretty lame.

My prints have been delaminating even at some pretty high temperature settings for a particular material, so I measured the hot end with my Fuke 87V’s thermocouple by pressing it against the hot end with a wooden dowel until the temperature stabilized. The reading were as follows.

Printer Thermocouple	Fluke Thermocouple		Difference
220							194.5						25.5
200							175.5						24.5
180							155							25

So is there some way to set a temperature offset? Was my test methodology correct?

Thanks for any input.
Ian

Hi Ian

your method is totally OK.
You might measure slightly to low with your Fluke as the ambient temperature still will have some efect but this should be minor.
I believe you should do some more Points below 180°C to see if your Offset stays the same.

I am not yet sure why you have those 25°C Offset in there. First thought was that you have a different Thermistor than the Firmware expects. Unfortunately I don’t recall what AO usually is using.
Never the less I do recall that some were was written that the Thermistor tzpe can be set in the Firmware.

All the best
Frank

Thanks for the response Frank. I will check the thermistor type. I also sent the question to AO support and I got the following response. I wanted to post it in case it is useful for someone else. I have not yet tried what they suggested. I wanted to brush up a little on PID controllers before I did.

Hello Ian,

Sorry about these temperature issue. Yes there is a bit of a temperature offset, it’s like a set of values so that your hotend knows how much power it needs to reach specific temperatures and they are called “PID settings.” Normally our printers are shipped with accurate PID settings, but if it is showing to be off we can adjust them.

Allow your hot end to cool to room temp. In the terminal in Cura, send the following command: M303 S230 if extruding ABS at 230. Change the number in the command to reflect the temperature at which you normally extrude. The M303 SXXX command will tune the extruder. Use M303 E-1 SXXX to tune the bed. The hot end will then heat up and finally cool, while logging the temperature. When completed, similar values will be displayed:

bias: 101 d: 101 min: 145.48 max: 154.02 Ku: 64.06 Tu: 29.67 Clasic PID Kp: 38.04 Ki: 2.35 Kd: 147.63

Enter that information into your Start Gcode in Slic3r using the following format, with your values substituted appropriately:

M301 P38.04 I2.35 D147.63 or for the heated bed: M304 P38.04 I2.35 D147.63

Enter the following command to save the PID settings to EEPROM.

M500

Reslice your model. Your temperature fluctuations should be lessened and more consistent.

I hope that helps. If there is anything else we can do to assist in the meantime please let us know.

Hi Rhombus

please let me know if that PID tuning really helped.
My wild guess is that it will not change anything as you are reading the wrong temperature with your thermistor.
Even though it is possible to have an offset in temperature caused by wrong PID settings, this offset you could read on the thermistor values as well. So thermistor reading and Fluke reading should be similar.

Thanks a lot
Frank