Itty Bitty Double Flex nightmare

[kd7eir]

I just installed the Itty Bitty Double Flex, flashed the firmware for it, did M502 followed by M500.
All of my prints seem to have about ten times too much PLA extruded.

I have attached a picture of the 2mm spacer that I printed before installing the Itty Bitty Double Flex, and one that I tried to print immediately after. I used the same GCode file in both prints.DSC_0009.jpg

[kd7eir]

This is really baffling. No matter what I print it comes out like garbage. I was getting very nice prints before this.

[kd7eir]

OK, lowering the extrusion multiplier is making a huge difference. I have used an extrusion multiplier of .90 in S3D forever and gotten great results. I'm down to .50 and getting ready to go a bit lower yet to get the right print.

[Chadd]

You probably haven't set the Esteps for your new extruder.

[kd7eir]

I will agree that I did not change them from the 615 starting point. Would that negate the necessity of lowering the extrusion multiplier? I went from an extrusion multiplier of .90 to .40 in order to get good prints. Maybe I went about this the wrong way...

[Alibert]

Yes, you need to adjust the e-steps in the firmware settings.

Not all extruders extrude the same length of filament for the same number of e-steps. If your slicer thinks that 615 steps will feed 1 mm of filament through the extruder, but in reality 200 steps are needed, then you are over-extruding by a factor of 619/200 = 3.095. You can adjust that by making the multiplier 1/3.095 = 0.32, but that is a kludge as the extrusion multiplier is intended to account for flow properties, not filament size issues. Better to adjust the e-steps in the firmware or you will have to adjust the multiplier for all filement types.

You can google the correct number of e-steps for the itty bitty and start from there (and reset the extrusion multiplier back to 0.9 for PLA in S3D).

[kd7eir]

Thanks for the advice. I ended up with e-steps at 200 and the extrusion multiplier set back to .90

[clough42]

Are you running 1/16 microsteps?

The 615 eSteps starting point is assuming that you're using the Clough42 hobbed bolt in a 4:1 drive extruder (all of the Itty Bitty extruders are 4:1) and 1/16 microstepping on the driver.

It sounds to me like your stepper driver is set to the wrong number of microsteps, which would result in exactly what you're seeing: massive overextrusion.

If you have a RAMPS board, this is controlled by the jumpers under the motor driver. Make sure all three jumpers are installed (for A4988 drivers). If you have fewer than three, that's your problem. You can compensate by dropping the eSteps value, but that also reduces resolution. You're better off with 1/16 microsteps.

[kd7eir]

So, in desperation I decided to take my RAMPS board apart and start all over.

And then I see that I had three jumpers on every stepper drive EXCEPT the extruder.

Mea Culpa!

Thank you to everyone that helped me!

[clough42]

So, in desperation I decided to take my RAMPS board apart and start all over.

And then I see that I had three jumpers on every stepper drive EXCEPT the extruder.

Mea Culpa!

Thank you to everyone that helped me!

Awesome! Glad to hear it's working.