Dual extruder drool I've just upgraded my new HE3D sky to dual extruders, but I seem to have a huge drool problem (or at least my printer has). [attachment 112643 20190903_072551.jpg][attachment 112644 20190903_072558.jpg] My biggest concern is the white line above the 'B'. It is fused into the green, and I really only want green there! I could live with the furry bits if I had to... they're easy enough to scrape off. But I suspect that they're another symptom of whatever is causing the blobs on the surface... probably furry bits that have got trapped during green extrusion. I'm not particularly concerned about the under-extrusion in the white region... I think that's just bad geometry in the position of spool and extruder. And the break in the model at the bottom of the white rectangle is I think because the printer tried to home to [0,0,0] after the print, right through the middle of the model. In case it's relevant, the white extruder is 18mm to the left of the green one, both printing PLA at 210C, and standby temperature is 175C (the default). I already have 6mm retraction, and I'm reluctant to go higher with that in case of jams. The model itself has 0.8mm thick walls, with some reinforcing inside. Sliced with the latest version of Cura. Can someone who has dual extruders please give me some pointers? Should I maybe lower the standby temperature? Would Cura's "ooze shield" correct this? https://reprap.org/forum/read.php?262,858836,858836#msg-858836 Thu, 12 Mar 2026 18:36:42 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?262,858836,858934#msg-858934 Re: Dual extruder drool https://reprap.org/forum/read.php?262,858836,858934#msg-858934
Quote
frankvdh
I've just upgraded my new HE3D sky to dual extruders, but I seem to have a huge drool problem (or at least my printer has).

[attachment 112643 20190903_072551.jpg][attachment 112644 20190903_072558.jpg]

My biggest concern is the white line above the 'B'. It is fused into the green, and I really only want green there!

I could live with the furry bits if I had to... they're easy enough to scrape off. But I suspect that they're another symptom of whatever is causing the blobs on the surface... probably furry bits that have got trapped during green extrusion.

I'm not particularly concerned about the under-extrusion in the white region... I think that's just bad geometry in the position of spool and extruder. And the break in the model at the bottom of the white rectangle is I think because the printer tried to home to [0,0,0] after the print, right through the middle of the model.

In case it's relevant, the white extruder is 18mm to the left of the green one, both printing PLA at 210C, and standby temperature is 175C (the default). I already have 6mm retraction, and I'm reluctant to go higher with that in case of jams. The model itself has 0.8mm thick walls, with some reinforcing inside. Sliced with the latest version of Cura.

Can someone who has dual extruders please give me some pointers? Should I maybe lower the standby temperature? Would Cura's "ooze shield" correct this?

I have played a LOT with dual color and had a lot of trouble with CURA doing what I wanted. I pretty much stay with Simplify3D which (IMO) has better dual-printing "knobs".
However, you can obviously use CURA to do dual color prints.
Use the breeze wall, drool shield, whatever its called.
Don't use the prime tower, I have never gotten that to work well.
Pull the unused head's filament back 10-12mm and drop the temperature to 165.
Drop your filament temperatures. I like BamTack and Hatchbox filament for my dual-printer. They will want 180-190C temperatures.
Use coasting and retract during the coast (if CURA has that setting).
Write your own tool-change scripts. I never got CURA defaults to behave well here. When I change heads, I retract big (12mm) move the end-effector out of the print entirely, and change hot-end temperatures while away from the print.

Sadly, everything that I have tried with CURA to get a good dual-color print ended up fighting with CURA defaults and gave me weird results. I chalk this up to not understanding all of the "innards" of CURA. Someone really good at driving CURA can probably give better help here. My advice if you do a lot of dual-color printing? Buy Simplify3D, it is stupid-simple to do dual-color with that slicer, but S3D makes you do the tool-change script yourself - However, there are a lot of examples out there that you can start with and tweak to perfection. FULL_DISCLOSURE: The only slicers that I have spent a lot of time with are S3D and CURA. There are others out there.

DLC]]> dlc60 Printing Wed, 04 Sep 2019 17:11:01 -0400 https://reprap.org/forum/read.php?262,858836,858892#msg-858892 Re: Dual extruder drool https://reprap.org/forum/read.php?262,858836,858892#msg-858892 dc42 Printing Tue, 03 Sep 2019 16:13:28 -0400 https://reprap.org/forum/read.php?262,858836,858836#msg-858836 Dual extruder drool https://reprap.org/forum/read.php?262,858836,858836#msg-858836
[attachment 112643 20190903_072551.jpg][attachment 112644 20190903_072558.jpg]

My biggest concern is the white line above the 'B'. It is fused into the green, and I really only want green there!

I could live with the furry bits if I had to... they're easy enough to scrape off. But I suspect that they're another symptom of whatever is causing the blobs on the surface... probably furry bits that have got trapped during green extrusion.

I'm not particularly concerned about the under-extrusion in the white region... I think that's just bad geometry in the position of spool and extruder. And the break in the model at the bottom of the white rectangle is I think because the printer tried to home to [0,0,0] after the print, right through the middle of the model.

In case it's relevant, the white extruder is 18mm to the left of the green one, both printing PLA at 210C, and standby temperature is 175C (the default). I already have 6mm retraction, and I'm reluctant to go higher with that in case of jams. The model itself has 0.8mm thick walls, with some reinforcing inside. Sliced with the latest version of Cura.

Can someone who has dual extruders please give me some pointers? Should I maybe lower the standby temperature? Would Cura's "ooze shield" correct this?]]> frankvdh Printing Mon, 02 Sep 2019 20:36:54 -0400