@peirof

The little micro explosions are most likely as some have said absorbed moisture that is boiling off.... most sites will tell you that PETG absorbs moisture quite well so if it's an older roll then it's likely to have a level of moisture.

As for temperature, you really need to test this for yourself on your printer, grab a temperature tower and print it out with varying temps.

I for example print transparent PETG @214c only going up to 220c max when i want it a little more fluid.
So at 214c i can extrude at 12mm cubed flow rate using a 0.6 nozzle, 0.4 layer, 0.8 width at 38mm/s, rock solid layer adhesion, no strings. If i have small holes <6mm then speed gets dropped to 32mm/s. I do run a high flow dragon hotend and can print faster but these setting provide good output, no blobs and at worst very fine hairs.

Cheers
Phil

Hi all,

I finally got sensible and at least run a G32 before each print on my large delta.
The bed is 600mm round 8mm cast tooling plate, unrestrained sitting at the bottom of the machine.
I use an IR probe with the nozzle height checked weekly.

The probe is conducted over a 400mm square build area that is a powder coated PEI spring steel magnetic plate.

When doing a G32 the output settles down after the initial couple of runs to the be as per the lines below providing the printer is not turned off.
At this time i'm printing close to 24x7, everything is good, just curious why the before numbers are different generally for the mean...

9/7/2021, 9:57:21 AM Calibrated 6 factors using 14 points, (mean, deviation) before (-0.069, 0.088) after (-0.000, 0.087)
9/7/2021, 2:04:27 PM Calibrated 6 factors using 14 points, (mean, deviation) before (-0.032, 0.087) after (0.000, 0.084)
9/7/2021, 6:13:54 PM Calibrated 6 factors using 14 points, (mean, deviation) before (0.014, 0.080) after (-0.000, 0.076)
9/7/2021, 10:26:49 PM Calibrated 6 factors using 14 points, (mean, deviation) before (0.034, 0.085) after (0.000, 0.082)

Thanks for any insight

I find it bizarre that in 2021 RRF still doesn't have basic statistically information available in a log file for uptime, print time, filament usage....
I read that when filament types were first provided that filament usage would be logged "in the future" seems the future is still waiting.

I know this sounds like a rant and you know what maybe it is..... I'd be happy with any of this to end up in a log file and i'll bet the people pleading for counters would be happy with the caveat that on a power interruption/loss that x minutes of data would not be available.

@dc42 Cool and Thanks.

Just 1 carriage with the nozzles a fixed distance apart. I was sure i had asked this years ago but searching turned up nothing, appreciate your time.

So creating a tool that uses both nozzles does that mean i need to to set up 3 tool definitions and target the correct tool when slicing or can i via the firmware itself either from the touch screen or the web interface say turn on ditto mode and have the firmware drive T1 and T0 despite the gcode being sliced only for T0?

What i mean by 3 tools is...
T0 - Primary normal nozzle
T1 - Secondary nozzle (used for support etc)
T2 - T0 + T1 running in ditto mode

What i'm used to is, slice for T0 and then on the FFC enable ditto mode and it just uses both nozzles.

interesting when i forget to turn it off and print something bigger

Cheers
Phil

Thanks, that will at least keep me travelling in the direction i want, hopefully DC42 might chime in with specifics

Cheers
Phil

Long time no post and a question as i commence turning bright ideas into a design for a new CoreXY build.

One feature i use a lot of on the FF Creator is "Ditto Printing" as in both hot ends print the identical object at the same time. Essentially both are T0. The creator limits you due to head spacing to objects thinner than say 34mm (36mm head spacing).

I'm thinking about building the CoreXY with two hotends but need to know if the Duet firmware can be set to optionally turn on and off the "ditto" functionality?

So if i have T0 and T1 can they be used independently as T0 and T1 as normal and then also be set up as 2 x T0 when needed?

Thanks in advance
Phil

So what is the expected maximum and how is it set?

(deep breath) (a few times)
semi rant on….. apologies in advance.....

From the wiki.... Tuning a hot end heater normally takes just a few minutes.
yet above you now say it will take about 7 minutes.

No where in the documentation do you discuss the expected maximum, how it is determined or if it is settable.
can you or should you tune for different setting ie PLA v ABS v even higher.

I know this is beta and we are testing but i've had 5 runs with different P values and all ended up going over S max each time but no useful ideas on what to look for further.

Is this a case that the default boot up tuning model just can't handle the high powered heater as it stands.

I'm somewhat astounded that what should be for the end user a simple no brainer exercise regardless of the heater power, you are collecting the temperature numbers as it heats and I would expect that the tuning would automatically handle the fast heating.

I have no doubt the behind the scenes firmware calculations are no where near as simple as i think of course.

rant off//

I understand that I continue to represent an edge case in all your testing but I would hope that is valuable as well.

@dc42:

The tuning runs at constant PWM (the value you select) and looks at the temperature profile. It stops when the temperature rise is a little less than 90% of the expected maximum.

I don't get it then..
my M303 for tuning on the last run was M303 H1 P0.2 S260, it took 11 minutes before it failed with over temperature at 260. this is well over the couple minutes you expect it to run.

1. Is the S value the "expected maximum"? It's not clear from the documentation.
2. if so why didn't my tuning run stop at 90%?

In that last run it got to around 240 and slowed up and above 250 it got really slow but never stopped rising till it hit 260 and then failed.

OK with p0.2
23:51:34Auto tune of heater 1 with P=0.20 S=260.0 cancelled because temperature limit exceeded. Use lower P or higher S in m303 command.
23:40:37M303 H1 P0.2 S260
Auto tuning heater 1 - do not leave printer unattended

I surmise that the tuning is looking for the max stable temp for a given pwm?

midnight here will try again tomorrow with even lower P values.

Cheers

@dc42:

Hi Phil, that just the means that your heater is rather powerful and you need to use a lower pwm for tuning purposes. This won't affect the maximum pwm used in operation.

Ta David,

Replied to the other thread as well, right at the moment trying at p0.2, will update other thread with results.

Hopefully this can be a guide for others with high power heaters.

Cheers

PS: all the other bits/updates seem fine.