So, what do we think about dual extrusion after a month?

[sprior]

I've noticed the message traffic has been low lately, so I'll try to start it up a little.

So now that the dual extruder upgrade has been out for around a month, what do we think?

I'll say that I like the V4 extruder. It might even just be the look of it, but I like it more than the V3B.

The only thing that bothers me about the dual extruder setup is the X stop. With a single nozzle system it made sense to me that when the nozzle was at (0,0,0) the nozzle was at the corner of the glass, and now it's off to the left of the glass. This just feels incorrect to me, and I think maybe the X stop should change for this. I once printed something that had just a millimeter or two to spare in the X direction and this new offset would be annoying to work around. The only downside I can see is that you wouldn't be able to purge the left nozzle off to the left of the glass anymore, I haven't done that and not sure that would be important. Otherwise adjusting the X stop makes sense to me.

Before I got my dual extruder I read the Simplify3D page on the topic and was impressed with how well they support dual. Then when I got it and ran into ooze issues I realized that S3D fell far short of Cura. Cura works for dual, but I miss the other features I paid for in S3D, but no idea when/if S3D will add ooze shield and wipe tower generation, or if that's even the right answer.

For me personally at the moment since I'm relatively new my best time has been spent lately getting better at my chosen CAD program (Autodesk Fusion 360) and not worrying about dual color models, but that's just because I want to be more comfortable creating my own things.

I'd like to see more chatter on tweaks and settings for dual printing.

[jsc]

The v4 extruder is an improvement.

For dual extrusion, having bone dry filament helps a lot. S3D's dual extrusion support has a lot wrong with it, even beyond lack of support for wipe towers and ooze shields.

I would like to get a fat .5mm nozzle for the right extruder for fast infill/support. And some dissolvable support filament. Dual color printing is situationally useful, but the need doesn't arise all that often.

The X end stop doesn't bother me. You could fix the origin problem with an offset, so that 0,0 is the corner. What does bother me is that when I home and tell the right extruder to go to X205, sometimes it happens correctly and sometimes it goes to X205+inter extruder distance. I'm not sure how to get it to understand which extruder I'm referencing. I've tried messing with the gcode, but haven't really done any rigorous experiments.

[markb]

I messed with duel printing for a bit but it was just ok. I really do not have a ton of parts that I need two hotends to print with.

I love the V4 and the solid nonprinted mounts.
I took off one hotend and have moved back to the old firmware. The V4 with solid mount and new filament drive is a winning combination.
It just works. I put some bad filament into it and to clean it out I just took the tip off ran some filament through it put the tip back on and I was good to go.
I did the exact thing with the V3 and hours later I was back to printing. I had to take everything off and then take it all apart.
My prints look a little better but this is not a big difference but I notice it.

I should add that I have only printed a couple things with PLA with the V4. I have done a lot of ABS printing with the V4. I have put about 5 pounds of ABS through the new V4 so far

[Tim]

I like my dual extruder setup and the V4 hotends. I have not had nearly enough time to play around with it. Got into a lot of heavy software development work over the past couple of weeks in addition to school starting for the kids, and all my free time got sucked out from under me.

On the other hand, I've been waiting for some rolls of filament to come in from the PolyMakr startup that I gave some money to on Kickstarter earlier in the year. They came through as promised, I just got the filament delivered to me this evening: One roll of some extra-tough formula of PLA (but apparently not any higher temperature than usual, more's the pity), some flexible PLA, and some interesting foam-like PLA that is supposed to have the consistency of wood (but without the wood fibers to clog up the extruder). I will need to spend some time seeing how each of these print, also switching them between the all-metal and lined hot-ends.

Since (lack of) dryness is said to be an issue that exacerbates oozing, I'd also like to spend some time trying my PET+ filaments, which are hydrophobic (I have three spools, white, gray, and clear). I have in the past observed that the PET+ oozes about as much as the PLA does, but possibly with the right retraction distance, I'll see a difference.

Trying to work two types of plastic into a single piece is also an interesting thing to try. Also there's the idea that you can use one type of plastic for support material and another for the piece you're building, and they will come apart much more easily than if you use the same type of plastic for both (apart from the whole topic of dissolvable support). Not sure what types of plastic work best for this.

I have heard that dissolvable support has been rather over-hyped, and the plastics do not so much dissolve as get kind of squishy, and they absorb moisture out of the air like crazy. It's a neat concept, but I'd like to hear more positive things about it before I give it a shot.

[Dave K]

...On the other hand, I've been waiting for some rolls of filament to come in from the PolyMakr startup that I gave some money to on Kickstarter earlier in the year. They came through as promised, I just got the filament delivered to me this evening...

That's good news. I kicked in some money to PolyMakr as well, for the same 3 filament package, and the wait has been killing me. I think they have been having some production issues with the faux wood filament.

[Capt. John]

Just as an observation, I'm waiting to see models that look clearly defined without the drippie-doos.
Have my kit on wait until S3D does program upgrades. I do not have, or want the skill level to re-write
the operating code to run the printer.

Interesting to see the stand alone v4 hot end used instead of the v3b.
Best reviews have been about this hot end.

[Tim]

It's a bit of overkill to have a dual extruder if you only want to use one at a time, but if you have both the all-metal v4 and the PTFE insert v4, then you've got two different (single) extruders to play with. Hmm, maybe they can come up with a quick-release extruder. If you can do it with a bicycle wheel, you can do it with an extruder.

[insta]

For what it's worth, my dual-struder Ultimaker calls for some insane retraction when tool switching. They do 17mm retracts (on a bowden). When I get mine set up, I'm going to try tuning for 12-14mm retracts between tool changes, plus the wiper.

[Levi8than]

For what it's worth, my dual-struder Ultimaker calls for some insane retraction when tool switching. They do 17mm retracts (on a bowden). When I get mine set up, I'm going to try tuning for 12-14mm retracts between tool changes, plus the wiper.

How far is the distance from the molten plastic to the extruder gear? All it takes is a little bit of molten plastic in your gear to ruin your day. Be careful. Maybe retract slowly and give it time to harden.

[Tim]

On the dual extruder v4 setup, I'd estimate about 25mm between the top of the heatbreak and the drive gear. Although the plastic should be plenty cool up at the top of the heatbreak, I'd suggest that as a retraction upper limit.