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Calibrating the Da Vinci printer using Repetier CFW
This is just a placeholder for a thread I'm trying to write up. It should take me about a week to get information sorted out for this thread.

Nothing to see here.

3 - PID tuning

Background: [spoiler]One popular feature that the Da Vinci printer uses is a very common method of heating the Hotend.
It uses a heater cartridge, which is basically a resistor that heats up as electrical current is applied.
In order for the printer/host software to control the hotend temperature, there is also a thermistor which constantly monitors the temperature, applying current to the hotend if it gets too cold, and stopping current if it gets too hot.

A problem arises when we try to heat up the hotend quickly, or just maintain a constant temperature. Since each device is slightly different, we need to tell the Host exactly how our equipment performs, so that it can compensate for differences, and allow you to obtain a consistent print output.

Unstable temperatures of the hot end can cause various issues, such as bed adherence, layer adherence, thermal banding, oozing and also gaps or spaces in the top/bottom layers of an object.

The best way to fine tune Repetier to our printers' personal thermal characteristics is to use the PID tuning function. This tells Repetier how quickly our hotend reacts to instructions for temperature change, how fast it heats up and how well it retains heat after the last instruction.[/spoiler]

To start the PID autotune process we will use:
M303 S220 C8

This will autotune the hotend at 220 degC for 8 cycles, to give a more accurate value.
When it finishes, the PID numbers will be shown in the bottom of your screen. You then insert these numbers in Repetier under Config menu - Firmware EEPROM settings.

I would recommend repeating this if something changes that would alter your printers' thermal characteristics, such as moving to a different room, change in weather (winter-|Summer), you start printing with the doors open/closed, etc
Nothing to see here
nothing here yet...
Nothing here either

M303 P1 S60

will tune the PID for the heated bed.

Just doing this now for the first time. Is it normal that the 3 values fluctuate considerably between different runs? Eg (for the hotend):

19:33:33.201 : Kp: 18.84
19:33:33.203 : Ki: 4.98
19:33:33.204 : Kd: 17.84

19:36:40.093 : Kp: 26.50
19:36:40.094 : Ki: 6.75
19:36:40.096 : Kd: 26.03

19:39:55.111 : Kp: 20.78
19:39:55.112 : Ki: 5.53
19:39:55.123 : Kd: 19.52

And the same thing with the bed, but additionally there is a huge difference between the readings obtained from the autotune and the default values in the EEPROM. Should I worry about this?
Update: the autotune values obtained for the hotend do not seem to work very well. After I added one set of values to the EEPROM, it would not reach the target temperature anymore but instead fluctuates at around 5ºC less. After reverting to the default values, it's working well again. I had no such problem with the bed temp though, the autotune values seem to work well, the temp looks stable (not that I had issues with it before, anyway).
This is the Repetier firmware EEPROM parameters
after flash of file -- repetier-0.91-alpha-davinci10.bin
into DaVinci 1.0 printer (gen 2 control board jumper pad no jumper)

Z axis steps per mm should be 2560 with M8-1.25 leadscrew on z axis

working on other parameter updates

:S[Image: DV1_R_EEPROM.jpg]
Anybody know if DaVinci 1.0 controller uses on each axis
microstepping? (driver setting)
1 -- 200 steps per rotation
4 -- 800 steps per rotation
8 -- 1600 steps per rotation
16 -- 3200 steps per rotation
You are using a 6 months old version of the firmware... use this one instead: and remember to reset your EEPROM to default settings afterwards.

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