No "Dual Extrusion Merge" option and other issues with Dual Extruder

I am excitedly but carefully following the instructions at to install a dual extruder on my TAZ 5. A couple of problems have arisen.

After flashing the firmware, it said is was done, LCD said DualMetal TAZ Ready, but the Next button on the wizard remained greyed out. I waited and waited and Next would not activate. I terminated the wizard. LulzBot TAZ 5 (Dual V2) was checked under the Machine menu, the same also showed up under machine settings, so I thought I was OK. It was a bit unsettling, none-the-less.

The real problem occurred later, however. I loaded the inner_square.stl and outer_square.stl. Following the instructions, I left clicked on the small, inner square, and then right clicked on the same small inner square. There was supposed to be an option for “Dual Extrusion Merge”, but that option does not appear on the context menu.

Has anyone experienced this problem? Does anyone have suggestions?

If it matters, I have Cura 18.03 on Mac OS X 10.11.3


I just tried the Windows version. It seems the Dual Extrusion Merge exists on the Windows version of Cura, but not on my Mac version.

If there is no option to do a dual extrusion merge, check “extruder count” setting in the machine settings window. If this number is set to 1, it won’t show any dual-related features. Try using the “change toolhead” button to pick dual extruder and it should fix this for you.

Thank you. LulzBot eventully figured that out for me. It was weired. On the Windows version the extruder count automatically updated when I selected the dual tool extruder. But on the Mac version it did not. I had to set it manually, and I would never have known to look for it. Thank you.