Extruder software improvements  

RE: Extruder software improvements

It is very easy to address the ooze issue with a simple change to the printer start-up gcode.

But the simplest is to wait until after mesh level to heat the nozzle.  Or, as many of us do, preheat to a hot temp that doesn't promote ooze, and heat the last few degrees after the mesh level is performed.

start heat bed to [print temp]
start nozzle heat to [185]* anti-ooze
wait for pinda to reach 40c  *helps mesh accuracy
perform mesh level
heat nozzle to [print temp]

purge & print

====== Here's my actual code ...

M115 U3.7.1 ; tell printer latest fw version
G90 ; use absolute coordinates
M83 ; extruder relative mode
G28 W ; home all without mesh bed level

; preheat things to a low temp
M104 S185 ; set extruder temp
M190 S[first_layer_bed_temperature] ; set & wait for bed temp
M109 S185 ; wait for extruder temp (not really needed, but ensures any excess plastic is malleable during mesh)

; soak PINDA then level
G0 X50 Y50 Z0.15 F3000; this is a good PINDA heating position
M860 S40 ; wait until PINDA is >= 35C
G80 N7 R5; mesh bed leveling

; heat to extrude temp
G0 X0 Y-3.0 Z10  F3000; this is a good nozzle heating position
M109 S[first_layer_temperature] ; set & wait extruder temp

; purge
G1 Y-3.0 Z0.15 F1000.0 ; go outside print area
G92 E0.0
G1 X60.0 E9.0 F1000.0 ; intro line
G1 X100.0 E12.5 F1000.0 ; intro line
G92 E0.0
M221 S{if layer_height<0.075}100{else}95{endif}

RE: Extruder software improvements

Tim,

I went to PruserSlicer-2.0, clicked on Printer Settings and replaced the code there with yours.  I also changed the M115 line to read U3.7.2, to indicate what FW version I have installed.

That’s where my knowledge ends.  A print thereafter did not use the code, so I assume it must be entered in the FirmWare 3.7.2.  It is not obvious to me how that is done.  The FW file is a stand alone file.

Could you elaborate more on the rest of the steps to activate your code.

Thanks

RE: Extruder software improvements

it's just in prusaslicer. you should be able to open the gcode file in any text editor and look at the code and it should match what you have in prusaslicer

RE: Extruder software improvements

did you re-slice it after the changes and you should save the modified profile and switch to using that one ( the default profiles are write protected)

RE: Extruder software improvements

After you change the startup g-code, you need to save a new printer profile by clicking the [O] disk icon upper left beside the MK3S name.

Be sure it is selected when slicing.  After the first time, Prusa Slicer remembers the choice and will continue using the new profile until you manually select another printer profile.

RE: Extruder software improvements

Posted by: Tim

It is very easy to address the ooze issue with a simple change to the printer start-up gcode.

But the simplest is to wait until after mesh level to heat the nozzle.  Or, as many of us do, preheat to a hot temp that doesn't promote ooze, and heat the last few degrees after the mesh level is performed.

start heat bed to [print temp]
start nozzle heat to [185]* anti-ooze
wait for pinda to reach 40c  *helps mesh accuracy
perform mesh level
heat nozzle to [print temp]

purge & print

====== Here's my actual code ...

M115 U3.7.1 ; tell printer latest fw version
G90 ; use absolute coordinates
M83 ; extruder relative mode
G28 W ; home all without mesh bed level

; preheat things to a low temp
M104 S185 ; set extruder temp
M190 S[first_layer_bed_temperature] ; set & wait for bed temp
M109 S185 ; wait for extruder temp (not really needed, but ensures any excess plastic is malleable during mesh)

; soak PINDA then level
G0 X50 Y50 Z0.15 F3000; this is a good PINDA heating position
M860 S40 ; wait until PINDA is >= 35C
G80 N7 R5; mesh bed leveling

; heat to extrude temp
G0 X0 Y-3.0 Z10  F3000; this is a good nozzle heating position
M109 S[first_layer_temperature] ; set & wait extruder temp

; purge
G1 Y-3.0 Z0.15 F1000.0 ; go outside print area
G92 E0.0
G1 X60.0 E9.0 F1000.0 ; intro line
G1 X100.0 E12.5 F1000.0 ; intro line
G92 E0.0
M221 S{if layer_height<0.075}100{else}95{endif}

Thanks for the timely response.  You never know when you might just help out more than one person having similar issues.  I have been looking for some solutions and this may well assist me in getting even fewer cleanups during printing.

I will be trying this in a few minutes.  I will let you know how it goes.

Thanks again,

RAH

RE: Extruder software improvements

OK, troubleshooting time.  I created a printer profile with the new gcode as above.  When I started the print, the extruder moved to the left front edge of the bed and appeared to sit down on the metal plate (Z = 0.15?).  The nozzle went to 185ºC and the bed to 60ºC.  

Then the extruder moved about 100mm back at a 45º angle (G0 X50 Y50 Z0.15 -) and sat there.  Presumably, it was waiting for the PINDA to heat, but nothing happened.  After (3-4 min), so I cancelled the print. After three tries (5min wait on last try). I gave up.

The presumption is the PINDA temp sensor is not working

I just finished the S mod a day ago and have done three initial prints so far using the default extruder gcode.

Is there a way to test the PINDA temp sensor?

RE: Extruder software improvements

it's under the support menu

RE: Extruder software improvements

As David said, there is a screen in the printer's support menu that will show temperatures.  Depending on your printer's environment, it may take a very long time to reach the temperature, though.  5 minutes is probably not enough in your printer's location.  Several weeks ago, I tried to use the method of having the printer wait for the PINDA temperature to hit 35 C before doing mesh leveling, and my PINDA sensor had not even reached 30 C after 40 minutes.  My printer is in a air conditioned, cool, dry basement with an ambient temperature of 20 C or less.  The gcode I had taken from another user's printer profile set the nozzle temp to 160 and bed temp to 60 while it waited, and those weren't hot enough to raise the PINDA temp enough.  It would reach maybe 25 C in about 5-10 minutes, then it would take about 10 minutes per degree after that.  I gave up on using that custom gcode after that.  

RE: Extruder software improvements

My support menu only contains the FW version and several web addresses.  I clicked on all and it went back to the Support screen each time.

Back to the ooze problem.  I don’t see any reference to the PINDA temp in the default startup gcode.  Is it necesary in the ooze code?

RE: Extruder software improvements

Posted by: lindharin

[...] I tried to use the method of having the printer wait for the PINDA temperature to hit 35 C before doing mesh leveling, and my PINDA sensor had not even reached 30 C after 40 minutes.  My printer is in a air conditioned, cool, dry basement with an ambient temperature of 20 C or less.  The gcode I had taken from another user's printer profile set the nozzle temp to 160 and bed temp to 60 while it waited, and those weren't hot enough to raise the PINDA temp enough.  It would reach maybe 25 C in about 5-10 minutes, then it would take about 10 minutes per degree after that.  I gave up on using that custom gcode after that.  

When 1st starting on this journey last year I'd set my bed to 60C for the PINDA warmup, then had the same experience as winter approached. I found that setting the bed to the greater of 65C or my initial print bed temp setting was sufficient to move it along. It can still be slow (5-10 minutes) 0n the 1st print of the day, but is fine for my purposes. You can always go higher with the bed temp during PINDA warmup, then reset to your "real" temp for actual printing. See line 5 in my startup gcode. (Edit: I'm updating the page, should be current in a few minutes.)

RE: Extruder software improvements

Ben - on the support screen, you need to use the wheel to scroll down past the FW version and web addresses, there are additional entries lower on that menu, but it isn't obvious that there is more.  

Bob - thanks!  I am pretty sure the code I used was from your notes on your web site (which is wonderful, thank you so much for making it available!).  I'll take a look at the latest version and give it another try.

RE: Extruder software improvements

Well, can't edit posts anymore. The line that sets the initial bed temp to the higher of 65C or the set 1st layer bed temp is:

M140 S{max(first_layer_bed_temperature[0],65)}  ; set bed PINDA warmup temp

RE: Extruder software improvements

In the rare cases where PINDA is reluctant to heat up, use 35c instead of 40c. 

M860 S35 ; wait until PINDA is >= 35C

In a 25c room (A/C blowing almost directly on my printer which is 6' from duct)  my PINDA hits 35 and 40 with only moderate delays. And is always >40c after a print,usually 45c.

Perhaps the firmware has some lame "printer must be Temp calibrated before this command will work" bug.  So also run Temp calibration and see if it has any effect.

RE: Extruder software improvements

A couple tips that I've found for the PINDA heat-up:

1. Before starting a print I start pronterface on a computer that is connected to the einsy, and "connect" to the printer (really this is just opening the virtual serial port on the USB connection). Then I start the print manually like I always do. Once the gcode progresses to the PINDA warm up the PINDA temperature is reported in Pronterface's serial window. (Because of this, I presume one could see a similar thing in any serial interface like maybe Octoprint?) I prefer this because unlike the support screen, this readout gives you one decimal place so you can watch the tenths increment.
2. If I notice that the PINDA is taking a long time or the temperature has stalled on the way to the target temperature, I tent over it with a piece of paper towel to insulate it from the outside environment. Once the temperature is reached and the extruder starts to move I remove the paper towel insulation. Be careful doing this as it may trap too much heat around the hot-end heatsink contributing to both heat-creap and possible softening of the plastic that makes up the extruder (remember, the hot-end is set to somewhere in the neighborhood of 160°C).

Hope this helps.

RE: Extruder software improvements

Posted by: Sembazuru

[...] Because of this, I presume one could see a similar thing in any serial interface like maybe Octoprint?) I prefer this because unlike the support screen, this readout gives you one decimal place so you can watch the tenths increment.

Octoprint's terminal display is perfect for this. It doesn't make things go any quicker, of course, but at least you can confirm that temps are indeed below your setting and get a sense for how much longer you'll have to wait.

I get impatient with the delay, but have resigned myself to putting up with a 5-15 minute delay to get a quality multi-hour print when necessary.

RE: Extruder software improvements

Thanks for posting the start-up Gcode. It seems to be working well (at 35). No startup drool - which is good.