Retract speed being ignored

Hi,

I've got an issue I'm trying to sort out, where the extruder speed in the printer settings doesn't seem to be taking effect while printing.

I've got it set to 100 mm/s, but while printing it seems to be retracting a lot slower than that. Setting the retract speed to 100 mm/s in pronterface and clicking the button makes it move quickly, as expected. But when using a file produced by Slic3r, the retractions are a lot slower.


Does anyone have any idea what's going on here? Looking at the G-Code seems to indicate 100 mm/s retractions, so I'm stumped as to what's going on.

Thanks in advance.

Here is some gcode you can use to diagnose this.

What it does is retract 3mm and unretract at 50 mm/s, pause a half second, and repeat at 60, 70, 80, 90, 100mm/s. You can edit this to change the amount retracted/unretracted, etc.

You should run this with the filament backed out of the hot end (not in the melt chamber) as this does not set temperature, and to avoid jamming.

Save it as something like "TestRetract.gcode" and run it like any other gcode.

G21             ; set units to millimeters
G90             ; use absolute coordinates
M82             ; use absolute distances for extrusion
G92 E0         ; reset extrusion distance
;
; -- Retract/unretract at 50 mm/s
G1 E-3.00 F3000.000   ;  retract
G1 E0.000 F3000.000   ;  unretract
G4 P500 ; dwell .5 second
;
; -- Retract/unretract at 60 mm/s
G1 E-3.00 F3600.000   ;  retract
G1 E0.000 F3600.000   ;  unretract
G4 P500 ; dwell .5 second
;
; -- Retract/unretract at 70 mm/s
G1 E-3.00 F4200.000   ;  retract
G1 E0.000 F4200.000   ;  unretract
G4 P500 ; dwell .5 second
;
; -- Retract/unretract at 80 mm/s
G1 E-3.00 F4800.000   ;  retract
G1 E0.000 F4800.000   ;  unretract
G4 P500 ; dwell .5 second
;
; -- Retract/unretract at 90 mm/s
G1 E-3.00 F5400.000   ;  retract
G1 E0.000 F6400.000   ;  unretract
G4 P500 ; dwell .5 second
;
; -- Retract/unretract at 100 mm/s
G1 E-3.00 F6000.000   ;  retract
G1 E0.000 F6000.000   ;  unretract

Put a mark on the drive gear, and on the filament so you can clearly see what is happening.
Watch and listen to the extruder carefully.
Is there a point at which it can not handle the speed?

You may need to attach your config file.

---

My printer: Raptosaur - Large Format Delta - [www.paulwanamaker.wordpress.com]
Can you answer questions about Calibration, Printing issues, Mechanics? Write it up and improve the Wiki!

Thanks Paul.

It turns out that I had a 25 mm/s limit set in firmware /Eeprom.

What confused me is that pressing the extrude/retract buttons in Pronterface seemed to go at full speed (100mm/s), while printing was limited to 25mm/s in firmware/eeprom.

Edited 1 time(s). Last edit at 01/11/2016 06:11PM by nebbian.

Where are you setting the retract speed to 100 mm/sec? If it's in the firmware but you don't check the "use firmware retraction" box in Slic3r, it will use whatever the numbers are in Slic3r.

If you're setting it in Slic3r and and you don't have the "use firmware retraction" box checked, it may be that the speed is too high and your extruder can't execute a 100mm/sec move.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Quote
the_digital_dentist
Where are you setting the retract speed to 100 mm/sec? If it's in the firmware but you don't check the "use firmware retraction" box in Slic3r, it will use whatever the numbers are in Slic3r.

If you're setting it in Slic3r and and you don't have the "use firmware retraction" box checked, it may be that the speed is too high and your extruder can't execute a 100mm/sec move.

Yes, that's what I thought. However that definitely wasn't the case.

Here are my settings:





And here's what was stored in EEPROM:

>>> M501
SENDING:M501
echo:V21 stored settings retrieved (380 bytes)
echoteps per unit:
echo:  M92 X80.00 Y80.00 Z80.00 E95.00
echo:Maximum feedrates (mm/s):
echo:  M203 X500.00 Y500.00 Z500.00 E25.00

Here's how I bumped up the EEPROM retraction speed:

>>> M203 E50
SENDING:M203 E50
>>> M500
SENDING:M500
echoettings Stored (380 bytes)

After doing this, the retraction speed was a lot quicker, it looked twice as fast to my Mark 1 eyeball.

So now I have 50 mm/s retraction (still limited in firmware/eeprom, not slic3r in the screenshots above) but that is fast enough for what I was hoping to achieve.

Maximum feed rates in the firmware are absolute limits that will be enforced no matter what you tell the machine to do in the slicer.

There may be settings for acceleration, distance, and speed of retraction in the firmware somewhere, separate from the absolute speed limit you posted.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Quote
the_digital_dentist
Maximum feed rates in the firmware are absolute limits that will be enforced no matter what you tell the machine to do in the slicer.

There may be settings for acceleration, distance, and speed of retraction in the firmware somewhere, separate from the absolute speed limit you posted.

Again, I agree with you, but please understand that when I used Pronterface, the speed was a lot quicker than when I used slic3r.

So for some reason when I used the interface of pronterface it disregarded the eeprom settings. This confused me greatly and set me off down the wrong path.