[Solved] Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)  

RE: Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)

Welcome Sylvain. 

I don't have a Prusa Mini, however, Looking at the Start Gcode, I note .... 

G90 ; use absolute coordinates
M83 ; extruder relative mode
M104 S170 ; set extruder temp for bed leveling    >>> this line sets the extruder to a low temperature during heat up, to reduce fialment dribbling
M140 S[first_layer_bed_temperature] ; set bed temp
M109 R170 ; wait for bed leveling temp
M190 S[first_layer_bed_temperature] ; wait for bed temp
G28 ; home all without mesh bed level
G29 ; mesh bed leveling
M104 S[first_layer_temperature] ; set extruder temp>>> this line sets the extruder to the desired temperature after mesh Bed Levelling
G92 E0.0
G1 Y-2.0 X179 F2400
G1 Z3 F720
M109 S[first_layer_temperature] ; wait for extruder temp>>> this line Waits for the extruder to reach temperature before starting printing

; intro line
G1 X170 F1000
G1 Z0.2 F720
G1 X110.0 E8.0 F900
G1 X40.0 E10.0 F700
G92 E0.0

M221 S95 ; set flow  >>> this line sets the extruder flow rate to a slightly lower value, to reduce over extrusion

I hope the notes in RED, help

run the print again, but HAVE FAITH!  it will come to the correct temperature...   🙂
regards Joan

Hurrah: you are perfectly right! What about some dimensions accuracy issues then?

@joantabb

Hello Joan,

Thanks to your detailed response, I checked the generated G-code from PrusaSlicer, and found almost same structure as per your description.

So I prayed and pushed the print button...and everything went as per your description! Perfect.

Lot of thanks for this!

So may I submit another question/concern to you please? 

Here it is: I designed a simple testing part, which I used on any new printer I bought It is a basic square shape (external side = 50mm) combined with a Ø 40 mm cylinder. Purpose is to check quickly printed sizes accuracy on X and Y axis  (phots attached). And here are my findings

Using a digital 25-50 mm micrometer I can measure this:

For external square shape measurements are 49,71mm (X) and 49,72mm (Y)

For the external cylinder Ø, measurements are: 39,60 mm (X) and 39,63 mm(Y)

So 2 comments: X and Y are pretty consistent each other. However dimensions are significantly bellow those defined into CAD file, with at least 0,3 mm missing.

So I have to find now where/how to correct this.

So far with other 3D printer brand I was using a simplify3D script with M92 command line to correct axis accuracy . I used the excellent XYZ calibrator described by  Danish 3D Printing  on Thingiverse (link: https://www.thingiverse.com/thing:2474201 )

Youtube:

I don't know if this is the same approach on Prusa, I will have to look at this during forthcoming days..

But, if you have some advices to give me regarding this...you are welcome! 😊 😊 😊

Thank you again for your detailed response to my first temperature concern!

Best regards from France!

Sylvain

RE: Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)

Unfortunately Silvain, I don't have a mini, and I haven't noticed this error on my mk2 or mk3

Could I suggest you try another print before you change anything... 

Make a model  100 x 100mm   if the problem is a scaling problem, the new print should end up 0.6mm undersize. if it ends up say 0.3 mm undersize, again, then the cause is probably something else.

it is really important to make  sure that you are actually correcting something that needs correcting rather than introducing new inaccuracies that change this particular measurement but cause problems elsewhere...  

Have you measured the wall thickness and compared it with the expected wall thickness?

regards Joan

RE: Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)

Just few days ago I read some article about overlaying print lines each other so having a 0.4mm diameter nozzle you cannot simply multiply 0.4mm times integer number and you will get the exact size you want. So this can lead that you will not get always the size you want.

Some remedy can reached setting the parameter print external perimeters first in PrusaSlicer.

It is somewhere on help.prusa3d.com

I do have dimension mismatch issue: I open a new topic

Hello Guys,

So I wen back to printing some test parts and made some measurements on them. 

I do have some dimensions differences on my Prusa Mini

But because this is complete another findings than the first one (temperature displayed) I open a new topic here, should you be interested (and helpful!) into this one...

Best regards

Sylvain

RE: Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)

Good Luck, 

Regards Joan

New topic for dimensions adjustment

Hello Joan

My data are here: 

https://forum.prusa3d.com/forum/assembly-and-first-prints-troubleshooting/prusa-mini-difference-between-cad-sizes-and-printed-sizes-both-x-y-and-z-any-correction-through-m92-command-on-prusa-slicer/

I will find a way because I'm convinced the Mini can produce far better accurate parts from dimensional point of view.

So I will update above mentioned new topic on this.

By the way, hope you can take care of yourself regarding COVID 19, because looks like to be a real danger this one...

Best regards from France

Sylvain

RE: Prusa Slicer T° set to 215°C...but PrusaMini screen indicates 170°C after print command(?)

The Mini does it mesh leveling at 170 then parks and sets the temperature to the setting you selected for your print. Once it has reached the printing temperature it will start printing.