Flexydually Over Extruding

I am having a problem with the ABS side of my Flexydually grossly over extruding on my TAZ 6.

I don’t believe the problem has anything to do with the print head itself, because I have a second Flexydually print head, which does the same thing when installed on that machine.

I have calibrated the E-steps.
I have the latest version of Cura, and I have updated the firmware.
Flow rate is set to 100%
Filament diameter is 2.85
IC3d ABS filament

Have you checked to make sure Cura has the correct extruder diameter set?

Is that the same as filament diameter on the material tab?

Yes, it is set to 2.85.

It’s the “nozzle” diameter – not the filament diameter.

To check, go into Cura Preferences -> Printers -> pick the printer -> Machine Settings
From there you’ll see a window with two tabs… one is “Printer”, the other is “Hot End” and dual extruder heads have two “Hot End” tabs so you’d need to check each of them.

That tab will have the “Nozzle” diameter. Make sure the nozzle diameter defined matches the nozzle diameter of the toolhead.

If using Cura LulzBot Edition, when you add a machine definition – it asks for both the machine and the print-head. It will define everything correctly based on that head. If you swap heads but don’t update the machine define (or just create a new definition for that alternate head) then you can get wonky print results.

The area of a circle doubles each time it’s size changes by a factor of roughly 1.4x (the actual number is the square root of 2, but 1.4x is close enough). E.g. a .5mm nozzle has double the area vs. a .35mm nozzle and 4x more area than a .25mm nozzle. This means that if the nozzle diameter in Cura is set to a value larger than the actual physical nozzle diameter, you’ll end up with over-extrusion.

You can have first-layer issues based on z-offset value. E.g. if the nozzle is too close to the build plate it can squish the filament fairly wide and end up with a poor quality result. This would happen even if all other settings (e-steps, nozzle diameters, etc.) were all correct. If you post a photo of what your printer is doing, the community might be able to take some guesses as to what is happening.

Thank you for the detailed reply. Both nozzles are set to 0.6. I am not sure how to tell what size nozzles I have. They are both original.

This is the first layer of abs.

First layer of ninjaflex

2nd layer of abs. This is as far as I got. The Ninjaflex side ejected it’s filament for some reason. Maybe a glitch because I was pausing to take a picture after each layer.

The FlexDually does use 0.6mm nozzles (assuming they haven’t been changed).

Thanks for posting those photos … it certainly looks like the nozzles are heavily over-extruding.

Another place to check is in the Cura “Prepare” menu. Make sure you’ve selected “Custom” (in the Print Setup category) and then scroll down to find the “Material” section. You’ll find a setting for “Flow”. While most materials tend to use 100% as the flow rate, sometimes it helps to adjust this. My default profile for NinjaFlex TPU sets the flow to 110% (TPU has a reputation for being “stringy” and doesn’t respond very well to retractions … so if you see a bit of stringing it’s probably ok). But if the Flow setting is way out of whack (set well above 100%) then it might explain the over-extrusion.

It might also be worth tracing through the setup steps to make sure nothing was missed.

You can find the setup instructions here:

https://ohai.lulzbot.com/project/lulzbot-taz6-flexydually-tool-head-v2-installation/accessories/

I aborted this print because the Ninjaflex nozzle was dragging a big glob around.

The ABS flow rate was set to 50%. The Ninjaflex was set to 100%.

In the one oi pictures, I peeled off everything except the abs so you could see the layers. It still looks like over extruding to me at 50% flow rate!

IMG_20200226_154847|666x500

Here’s the full print.

I was just reading on another site that some of the shell settings could cause the kinds of issues that I am having. I have checked and double checked every suggestion Tim has given me so far. Is there anything I should be looking for with shell settings?

I don’t know how any setting could be so screwed up. I have a new download of Cura, and I’ve reverted everything to default settings several times.

What is your Flow percentage set to on Extruder#1
What is your Initial Layer Flow Rate percentage on Extruder#1

What is your Flow percentage set to on Extruder#2
What is your Initial Layer Flow Rate percentage on Extruder#2

What is your Flow Rate percentage on the LCD screen when printing?
Wait for it to get past the first layer and see if that changes or remains the same.

Also, according to Matterhackers and public comments about the Flexy Dually you cannot print rigid filaments in the flexystruder toolhead side.