@Aeroxx_creative
Although you can't import the gCode, you can open the file using a 'text editor' and read the header and/or translate the gcode instructions.
These are just a few extracts from the Cat gCode:-
; printMaterial,PLA
; printQuality,High
...
; layerHeight,0.1
; useRaft,1
...
; infillPercentage,15

M140 S45 ;bed temp =45'C
M190 S45
M104 S200 T0 ;nozzle temp = 200'C

I hope this helps.

@TonyMM
I'm just using the Cura slicer software.

With my old laptop connected to my CR-10-V3 printer I slice, then select Print via USB and just print.

The Monitor screen shows details;

You simply say "...looking for the solution (M300) codes do not work." So I don't know exactly what you have tried.

Therefore my input may not be any help to you, but may help others that are searching this forum for answers.

The two basic requirements for sound are;

• a printer controller fitted with an audio transducer
• a recent version of Marlin (although mine is v1.1.6.0)

The audio transducer on my CR-10-V3 appears to be a simple D.C. voltage device which produces a single fixed frequency.

I tested it using Pronterface on a Linux computer linked to my printer. Any frequency > 0 produces the same sound, but the length can be set.

Example:-
M300 S1 P1000
...where S=frequency & P=duration, makes a sound for 1 second (1000ms).

Using the Cura Slicer software (V4.9.0) I added a simple sequence of codes to the end of the Machine Settings Start G-code section:-
M300 S1 P1000
M300 S0 P500
M300 S1 P1000
M300 S0 P500
M300 S1 P1000

...and something similar to the end of the End G-code section.

So now all my prints include a very annoying sound just as the printer starts printing and when it has just finished printing.

@ims
Yes, I think the first layer will be the print quality/layer thickness + the thickness of the paper.

I just measured an A4 sheet of standard weight copy/printer paper using vernier calipers and it was 0.1mm thick. So setting the bed using this paper, and for a quality/layer thickness set to 0.2mm in the slicer, the print nozzle will be about 0.3mm above the bed when printing the first layer. This should give good results.

If the print head is too close to the bed, the first print layer will be more "smeared" on the bed than it is when the gap is larger.

Yes, the power switch should be set to match your countries supply voltage.
So 230V for Europe, and probably 115V for north America.

Most people start with a sheet of printer or photo-copy paper. The important thing is to create a small uniform gap between the print nozzle and the printer bed. A sheet of A4 printer paper is something that many people may already have or can easily get hold of.

I am now using an ancient set of metal "feeler gauges" which I used to use to set the spark plugs on my cars...back in the day.

I use the 3 thou gauge as this equates to around 80nm (0.08mm) which I believe is about the thickness of printer paper.

@Alain_Reiner
Ok Alain, I may have underestimated your problem.

When the nozzle/hot-end is heated to (say) 200'C, the filament may flow out of the nozzle for a short time, but it should not keep coming out like a leaking water tap. This is because the filament is driven by the feed motor, which should not be running until the material is required for printing.

Even when printing, the extruder motor only pushes the filament through the hot-end/nozzle when required, and even retracts the filament (pulls it back a short distance through the extruder) when not required.

I don't know what your problem is, if heated filament keeps coming out of the nozzle for more than a few moments.

• Is the extruder motor slowly pushing the filament? (on my CR-10-V3 I can easily see when the extruder motor is turning in either direction, but I don't know the layout on your printer).
• How long does the machine keep extruding for? (e.g. 1min, 5mins, forever!)

Getting help on this strange forum appears to be really difficult. There are far more unanswered questions here than I am used to from my experience of technical forums. (where are the experts, where are the Creality insiders?).
So I am sorry if my suggestions are not much help, but at least I am trying.

I have not been using my Creality printer very long, but I now level the bed with the bed set to the working temperature (say 50'C).
I do not heat the hot-end/nozzle because of the same problems that you mention.
Instead of using paper, I use metal "feeler gauges" and aim for a gap of between 50-80nm (0.05-0.08mm).

Make sure you remove any extruder plastic while the nozzle is cooling down, prior to levelling the bed (I use a small mirror to inspect the nozzle, with the print head raised maybe 80mm).

I hope that helps.

I'm pretty new to this myself, but as no one has answered so far, this is what I do;

• pre-heat the hot-end (185'C for PLA)
• while its heating up, raise the print-head to (say) z = 100mm via the menu
• once heated, rotate the cog on the print-head forward and insure that hot plastic is extruded (i.e. no blockage), and then remove the extruded piece of plastic
• rotate the cog backwards while holding the filament with the other hand, pulling lightly to sense that the filament is coming out
• once the filament is free of the jaws, you will be able to just pull it out
• re-load new filament

I hope that helps.

After maybe 300hrs of printing, over the first 8 weeks of use on my CR-10-V3, I started having problems with my prints; mostly holes and snotty blobs.

Changing the nozzle has fixed the problem, but that has prompted me to ask three questions:-

1. How long would you expect a brass nozzle to last using standard (non-abrasive) PLA?
2. How can you check that your nozzle needs replacing (other than waiting for print problems) i.e. can it be measured or just inspected?
3. Where can I get good quality replacements (UK supplier prefered)?

There are pictures of the worn nozzle & bad prints here: http://captainbodgit.blogspot.com/2021/04/3d-printing-time-to-replace-nozzle.html

@renegadecitizen I'm new to this, but on my CR-10-V3 the hot-end fan does not run while the hot-end is being heated. I don't think the fan starts until after its printed a couple of layers.
Maybe you can turn the fan off in config (e.g. Dat file/EEPROM or whatever).