Why is my 3D printer over extruding when I have set the flow rate very low

  • Hello I am using Cura to slice my prints, and despite turning the flow rate to the minimum value of 5%, my prints are still hugely over extruding.

    I have calibrated the extruder stepper perfectly, using Pronterface, so I do not understand why this is occurring. I have also timed how long it took to extrude a certain length and compared it to the length of time it was meant to extrude and it was exactly the same. Therefore, I have concluded it is not a problem with the calibration of the stepper.

    So, I think there is a problem with the settings on Cura. Orginally, I had the flow rate at 100% and this was really, really terrible. Then I turned it down as far as possible and the print got better but there was still over extrusion. I can't down it down any further.

    I can not figure out what the problem could possibly be and as you would imagine it is very, very frustrating.

    Here is the print profile:
    Screenshot of Print Profile

    Edit - Some extra information

    So the printer is not of any model, as it is homemade CD drive 3D printer. It shares many similarities with the Curiosity3D printer, so if you want more information on how it works, then their website will be of much value.

    The extruder is a bowden style one. It uses a cheap e3d hotend Link to amazon and a RepRap extruder kit as the motor Link to amazon.

    Here are the Machine settings:

    Screenshot of Machine settings

    This is a photo of two failed prints. On the left is a G and on the right is a heart.
    Photo of two failed prints

    This is what it was the G was meant to look like:

    Pronterface G

    Edit 2 - More information

    So here is a link to the configuration.h file which I previously modified for my 3D printer.Dropbox link

    Also the filament I use is "Robox PLA SmartReel Cornflower Blue" link

    Any help would be much appreciated.

    210 is a bit much for pla, i suggest going for 185 or 195. Do you have a picture of the result you get? You say its under extruding but with a picture we can determine better if it is or not.

    Maybe you do not have microstepping enabled (so extruding, for example 16 or 32 times too fast)

    @Valmond I currently have all three jumpers slotted onto the pins on the extruder stepper driver area of the ramps board. I thinks this give 64x microstepping. Is there a setting I have too change, if I do this?

    No, if it would have been the other way around then maybe, but for this you seem to be good. Now with your added printer info, what firmware do you use? If it is Marlin (as the Curiosity3D does), then check the extruder configuration! You have direct drive (as Curiosity3D ), many use geared down drive which could be your problem. Have you flashed it yourself?

    1) Plz post Configuration.h from Marlin firmware 2) Is the EEProm activated?

    @Valmond Ok, so I have now added a link to the configuration on Dropbox. I do not know what EEProm does, but it seems "EEProm_settings" has been commented out. It seems that my motor is direct and after looking through the configuration it appears there is a section where I need to change "false" to "true" if I have a direct extruder, which I had not done. I have now changed this, but the problem still persists.

    At first glance (line 527) values seems reasonable (if, as your sceencap states, your printable area is 37mm wide etc.). Is the printed item, roughly,correctly sized? If so, remove the bowden tube and make your controller software move, say, 100mm of filament through the extruder (mark before & after + measure), how much is it off ? -> correct line 527 (fourth value) + compile + flash ->redo testing until ok. EDIT: as eeprom seems disabled, maybe you are not overriding values with the 5% feedrate? Please tell.

    @Valmond So, it seems to be printing at the correct size. I have also previously calibrated the extruder motor's steps per mm. I don't get how I can check if the the 5% flowrate is overriding values or not. What values is it meant to override?

  • Joe Clinton

    Joe Clinton Correct answer

    4 years ago

    I fixed this issue a while back but I realised others might see this. I’m not exactly sure what fixed it though. I was meddling with the ee-prom when suddenly it started working again. I suspect somehow a different steps per mm value was stored on the ee-prom so no matter what I did to change it (in the firmware) it made no difference. Then I either changed the settings in the ee-prom or disable it. I can’t really remember.

    When it started working it looked like nothing was extruding because 5% extrude rate really is very low!

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Content dated before 7/24/2021 11:53 AM