Extruder pushing too much ABS

I have finally gotten everything moving and the extruder is pushing way too fast. It is slipping constantly without moving the ABS and the melted ABS ends up just mounding way over and it is just too much. I have tried to adjust it in Slic3r but all the settings match my printers specs. Did I miss something in Marlin?

I found in Marlin that line 239 #define D_FILAMENT was set too high, so I changed that and reloaded it with no effect.

The setting in Marlin for steps per mm needs to be set correctly for your extruder and for your X, Y, and Z motors. The correct settings all very much depend on exactly what hardware you have. The default settings are rarely correct. There are simply to many printers out there.

You need to calibrate the extruder there are many posts on how to do that. The extruder extruding accurately in my opinion is the most important thing to get good prints

To calibrate the Extruder
1. Take the Extruder out of the Nozzle
2. Feed the ABS or PLA
3. Extrude 50 mm or 100 mm
4. Measure the Length Extruded
5. Note down the Expected length and extruded length readings
6. Change the Extuder Steps per MM in config.h in firmware by calculating Expected steps per MM in E

Here we go
x is the desired steps per mm need to be calculated (unknown)
y is the present steps per mm in config.h firmware

x = y * Expected length / Extruded Length

7. Update it in firmware and upload the new modified firmware
8. Do the above steps more than 1 time with lengthy extrusions
9. Update the repeated or average values in Extruder steps per mm

(There are some options with out changing the firmware it can be done by applying gcode directly to printer by changing EEPROM settings but I find difficult sometimes, so I don't use it)

---

Enjoy life

One subtle issue - if you have eeprom settings turned on in your firmware, they will / may override the settings you flash to the part. What they do or don’t do depends a lot on exactly what is on your Mega board (or equivalent) .

I couldn't find it in configuration_H but it was in configuration_ADV.H. Online 240 I found #define STEPS_Mm_E 863. I cut off a piece of filament 400 mm long and market at the 100 mm point. I told it to extrude 100 mm in pronterface and it ran the whole length of the filament and then went approximately twice as long. I shortened the value to 400 and uploaded it to the board and ran it again. It's behavior did not change at all. I reset the value to one, uploaded, ran it again, no change in behavior and it still advances much more than 400 mm of filament. Could this be what Bob is talking about with the eeprom settings? To my knowledge I have never touched the settings before, I will try to look into it this weekend if someone doesn't mind telling me what to look for. Thanks.

EEPROM settings is used for the same purpose that you have tried by changing firmware (in simple both are same)

Which firmware you are using ?

if your firmware is Marlin you can find the steps per mm of E in the following line in configuration.h (around line no 360)
#define DEFAULT_AXIS_STEPS_PER_UNIT {126,127,5120,1800} // default steps

here
126 is X axis steps per mm
127 is Y axis steps per mm
5120 is Z axis steps per mm
1800 is E axis steps per mm

Change the last one reduce by half and try it hope it will work

Edited 1 time(s). Last edit at 12/05/2013 11:30PM by GowthamJGR.

---

Enjoy life

Yes, I'm using Marlin. Thanks for the suggestion, I will look for it Saturday.

So it will work Definitely for you!

---

Enjoy life