Geeetech prusa i3 pro B quality issues

[organotis]

Hello,
I have a prusa i3 pro b from geeetech. I have some quality problems with it. You can have a look on the below pictures and let me know what do you think it is the problem:
https://www.dropbox.com/s/hewpedzapw..._3723.jpg?dl=0
https://www.dropbox.com/s/2srwazvspd..._3724.jpg?dl=0
https://www.dropbox.com/s/k90njujdxl..._3725.jpg?dl=0

I know that nozzles temperature does not fluctuate for more than 2 degrees Celcius. The Z axis are also calibrated. The filament that I currently use is Esun PLA but the issue occurs with almost any filament.

[mjf55]

Hello,
I have a prusa i3 pro b from geeetech. I have some quality problems with it. You can have a look on the below pictures and let me know what do you think it is the problem:
https://www.dropbox.com/s/hewpedzapw..._3723.jpg?dl=0
https://www.dropbox.com/s/2srwazvspd..._3724.jpg?dl=0
https://www.dropbox.com/s/k90njujdxl..._3725.jpg?dl=0

I know that nozzles temperature does not fluctuate for more than 2 degrees Celcius. The Z axis are also calibrated. The filament that I currently use is Esun PLA but the issue occurs with almost any filament.

So, some basic questions.
What extruder and bed temperature are you printing at?
What is your part cooling fan set to, and on what layers?
You say you calibrated your z-axis, how? what height did you rest to?
Any other model print this way?
Did you calibrate your extruder ( i.e. make sure when you tell it to extrude 10mm, it extrudes 10mm )?

[Roxy]

Hello,
I have a prusa i3 pro b from geeetech. I have some quality problems with it.

You sound surprised! I have a very low opinion of Geeetech quality.

With that said... Those prints are not that bad. It looks to me like it is under extruding at times. It could be an occasionally plugged nozzle. But I think it is more likely the extruder stepper motor is under powered. (Geeetech does put low torque stepper motors on the printers I've seen.) Can you turn the power up to the stepper motor?

One test to confirm this theory is try printing that same object but with the nozzle temperature 10 degrees higher. The print will look bad. But if you aren't seen 'under extrusion' it is because at the higher temperature, the filament is easy to push through the nozzle.

[organotis]

So, some basic questions.
What extruder and bed temperature are you printing at?
What is your part cooling fan set to, and on what layers?
You say you calibrated your z-axis, how? what height did you rest to?
Any other model print this way?
Did you calibrate your extruder ( i.e. make sure when you tell it to extrude 10mm, it extrudes 10mm )?

What extruder and bed temperature are you printing at?
I am using MK8 extruder.Material I am currently using is Esun PLA. Bed temperature is set to 60C. Nozzle temperature is at 228C on first layer and 225C the rest.(I know that is quite high for PLA)
What is your part cooling fan set to, and on what layers?
The fan which is on side of the stepper motor with the "heatsink" works at 100%. I do not think although that this is cooling the part.( I may also be wrong.I think that this fan is cooling the stepper motor only)
You say you calibrated your z-axis, how? what height did you rest to?
I place a caliber on the z axis on both sides between the horizontal rod and the table which the printer is on. The height was on home coordinates.
Any other model print this way?
Almost all prints have mostly same issue. Rarely a print is absolutely perfect.
Did you calibrate your extruder ( i.e. make sure when you tell it to extrude 10mm, it extrudes 10mm )?
The extruder was calibrated 2 months ago as you mentioned. Before calibrating it I had over extrusion (11mm instead 10mm)

[organotis]

You sound surprised! I have a very low opinion of Geeetech quality.

With that said... Those prints are not that bad. It looks to me like it is under extruding at times. It could be an occasionally plugged nozzle. But I think it is more likely the extruder stepper motor is under powered. (Geeetech does put low torque stepper motors on the printers I've seen.) Can you turn the power up to the stepper motor?

One test to confirm this theory is try printing that same object but with the nozzle temperature 10 degrees higher. The print will look bad. But if you aren't seen 'under extrusion' it is because at the higher temperature, the filament is easy to push through the nozzle.

Before 2 years when I bought this printer after assembly and first calibration I measured with multimeter what is the actual voltage on those stepper motor controllers and find out what the voltage was fine. I have not checked after that what can be the voltage. I can actually measure now and let you know.

[organotis]

I did measure the Vref fort the A4988 made by Geeetech. The Vref must be within 0.8V-1.2V. In my case the Vref was 0.9V on all 4 stepper controllers. I did raise the voltage to 1V and try to print something someday this week.

[Roxy]

The Vref must be within 0.8V-1.2V. In my case the Vref was 0.9V on all 4 stepper controllers. I did raise the voltage to 1V and try to print something someday this week.

I pretty much have all of my stepper motor drivers putting out the max current. The stepper motors get hot enough it is uncomfortable to hold your hand on them for 30 seconds. But I have not killed a stepper motor yet doing that.