Hi, I'm Aiden from Core Electronics, and today we've got the new dual extruder from LulzBot here, that's this one over here, and we've also got the old version 2 dual extruder. We're going to take a look at dual extruding, what that means for makers and people that are interested in 3D printing. We're also going to have a look at what these two tool heads do and how they do it, and finally we'll come to some conclusions about dual extruding and where it's going to take us with our 3D printing.

So first off let's cover off on what dual extruding is. These are both dual extruders and what they do is allow you to use two different filaments at the same time when 3D printing. Now I don't mean actually at the same time, you're not fusing, you're not depositing both the filaments at the same place at the same time, more so you're able to use two different filaments during the same print. So that could be a multi-coloured print or a multi-material print, think rigid and flexible materials being used at the same time, or interestingly one of our favourite applications would be to use soluble support material, meaning that you can print your supports using a material that dissolves when added to a certain liquid. There's PVA materials out there that just dissolve in water, so that's a really interesting application for a dual extruder.

Let's take a look at the similarities between the two tool heads before we dive into the differences. So obviously both tool heads use the same gantry mount, so this is used to connect your tool head to your printer x-axes, so the angled part here just slots in and then there's a small bolt that holds it from this hole on each of them, so it's the same bolt on both. On the back we've got a sticker with the serial number on both, which is similar, but down the bottom on the version 2 we actually had the e-steps written in by LulzBot staff when they put this tool head together. On this one we don't have those e-steps and we'll get to why that is in a second.

The next thing we'll talk about is the stepper motors. So first off we'll look at the V2 tool head and what they did with the stepper motors here, and then we'll look at the version 3. So the stepper motors here were oriented front to back and that was because the extruders down the bottom were oriented front to back. Now what this did was it made the depth of the entire tool head much greater, but it also put a lot of the mass on the front of the tool head, which we'll talk about in a moment, was actually quite bad for things like print speed as there was issues with wobble while the printer used the tool head. Have a look at the version 3 and what they've decided to do with it, and we'll take a look here. Now you can see just the black NEMA 17 stepper motors are in, but instead of being mounted front to back, they're mounted side by side and they're right up against that gantry mount plate, putting all the mass towards the mounting point for the tool head, which is quite important. By doing that it removed that cantilevered sag effect that we saw with the V2 tool head, and I think that's a really good design change for the new tool head.

Next up would be the extrusion cooling or the part cooling. So the version 2 tool head used these 40mm fans that you can see in there and they're mounted this way, so the air is blown down through the fan shroud and goes straight onto the printed part. It's a good design and those 40mm fans move a lot of air, so it always worked really well, and what we've seen on the version 3 is a very similar design there, but instead they've gone with the more direct angled fan shrouds that blow the air in, and this is borrowed from what we've seen on the more extruder and the single extruder 2.1 with Oswald, which is the one you get with your TAS-6. So that's another similarity, I mean they've changed it a bit, but it's also given it quite a cool look and it's made it wider but not deeper, so you can see that that tool head is quite thin compared to the V2 tool head, and if you take the measurement that's about 120mm-ish to 75mm with the dual extruder, so quite thin comparatively.

And finally another similarity being the 0.5mm hot ends are used on both extruders, both the V2 and the V3, and similarly both tool heads use the direct drive extrusion system. So both of them are, they've got their separate motors mounted to the tool head and it pushes the filament down into the extruder to be extruded, but you will notice that there's a massive difference between this Wade style extruder system here and this extruder system here with the new aluminium idlers which we'll get to in just a second. So that pretty much covers off on what is the same between the two extruders. Most of the hardware is the same, it's the same separate motors, it's the same hobbed bolt for most parts, it's you know the same extruder idea.

Let's take a closer look at what the differences are and why they are different. So this is the V3 tool head here and the first thing you'll notice is one of three things probably. You'll probably see this big black faceplate here. If you look closely you can actually see that the extruder number is labelled on that front faceplate. Either that or you'll notice that the gears are different on here or quite simply it's the big fans on the side here. So let's start off talking about why they've chosen to use this faceplate and what that means for us as makers. So when you're slicing your model files using Cura, you'll be using Cura 2.6 which is the new LulzBot edition Cura, you're actually asked what extruder is using what filament which is quite important, otherwise you might invert the filament choices and make a mess. So in the old Cura system with the V2 tool head it wasn't immediately apparent which extruder was which number. So you had extruder one and two but you didn't know quite which was which. On this one it's quite clearly labelled and that's probably why they've chosen to go for that. The next change would be the difference between these herringbone style gears on the V2, these 3D printed gears which obviously look quite cool and it's quite a thing that LulzBot likes to do is use as many 3D printed parts as they can. But then they've opted for these spur gears instead which is quite a different thing that we haven't seen before in any tool heads. Indirectly what they've done is, or probably directly, is they've really nailed down on the e-steps value.Now with the herringbone gears, there was a tolerance with that 3D print, which meant that every tool head had to be calibrated for the e-steps value before it was shipped. The firmware update that you will install onto your TAS 6 or your TAS 5 when you install this 3D tool head will actually update the e-steps value for you, and it will always remain constant, which is massive for reliability, which LulzBot is and always has been known for with their 3D printers. That's quite cool. I really like the idea of using these spur gears, and they look really good, so that's always a positive.

The next thing we'll talk about is this massive heatsink fan, which we didn't actually see on the V2 anywhere. What the V2 did have, if you can see it, it's quite difficult to see, we can have a look at this one, is one of these little micro blower fans. Now this was actually mounted to the 3D printed chassis of the tool head with one screw and it was directed, purely directed, at the heatsink here. If you can see that in there. Now the problem with that is right here it was really flimsy and it fell apart really easily. The screw actually went to the 3D printed layers on the angle that you wouldn't have expected, it wasn't very strong and yet as you can see it breaks really easily. So that was a bit of a gripe from the community I think that was really well covered off on with this change.

So now we have a shared heatsink for the heat breaks on both extruders and that big 40mm fan blasting air straight down into it. So that should remove any heat creep issues that we saw with the V2 tool head. The next thing that you will notice is probably the extruder orientation. So like we said before, by changing the way these extruders were oriented, we've done, Wellespot have done two things. They've moved the stepper motors to the back of the extruder making the entire thing a lot thinner and putting all the mass at the back of the printer, at the back of the tool head sorry, but also they've made the distance between the nozzles, what's that, about 15mm. On the V2 tool head, that was closer to 50mm. So what that meant was when you calibrated your slicing software for the tool head, there was 50mm between it and it actually decreased the amount of bed space that you could use to print your models with because there was just so much taken up by this extra extruder. So this second extruder couldn't actually get to the back of the bed. When the bed was moved all the way forward, you still couldn't access it with the second extruder. So it was just deactivated in Cura, which was quite a pain. So doing this, we've actually opened ourselves up to be able to use a lot more of the print bed. I know that these tool heads ship with an extended nozzle wiping pad that you install as part of the installation process for your V3 tool head, which means that you can clean both nozzles at the same time. And there's also an extender for the level switch at the start of the print level sequence. So tons of changes there just from the change of the orientation of the extruders.

Finally, let's take a look at the filament drive system. So we talked about those spur gears and what that meant for the whole extruding system, but let's take a look at these aluminium idlers, how they work and how they're different to the old styled ones on the V2. On the V2, you would apply tension to your filament using this extruder idler, and then the idler tensioner here, you'd move it with your thumb and lock it in. And you could change the tension by turning these bolts. And that was the same on almost every extruder. I think every extruder used this same system. So yeah, it worked well. Sometimes people had issues where these 3D printed parts might break, but for the most part, this system works really well. What we can see on the V3 toolhead is these big aluminium idler tensioners and the bolts, still the same idea there, where you can turn it to tension it and loosen it. But instead of pulling them up in that really weird and awkward way, it's far more ergonomic. You just simply pinch these two together and the filament will pull out. Same thing in reverse. Remove tension, feed the filament in, let go of them, and then turn that wheel to feed it down into the extruder to start extruding. So that's a massive change, and I think it's a really smart change from LulzBot there.

So there you have it. That is pretty much a quick rundown of the Dual Extruder V3. Now, I'm super keen to get this one going on our TAS VI so I can show you guys all the things you can do with it, but we'll quickly run over all the design changes and what they meant for us. So first off, the biggest advantage is easily the change of the extruders. So now the extruders are side by side mounted really close together rather than front to back. That changed the entire design of the toolhead. So now we've got all the stepper motors mounted against the mount point, meaning all the mass is there and we don't have that sag effect in longer prints. As you can imagine with all that weight at the front, it would actually bend and sag over time, which would throw your whole printer out of alignment indirectly. That also means that you no longer have to level your toolhead using this screw here, which was quite a pain. Now it will level using the auto leveling sequence, and this one will be only a fraction of a mil out from that. The filament drive system overhaul is obviously massive. What it does mean is that it's no longer important to only print using rigid filaments on the dual extruder. This is now essentially a dual extruder. It could be a flexi extruder, a flexi extruder, sorry, or a flexi jewelry. You could print with any combination of any filaments with this V3 dual extruder, which is really exciting. Next up would be my favourite part, only because I had to toil away with this V2 toolhead for so long with heat creep issues, is the heat break cooling system. I'm really excited to see this work exactly as I expected. Finally, the overall look of it is much better. It's much more sensible, and changing filaments in and out is going to be a lot easier with these new idle attentioners. Overall, a really great job from Lowellspot, and I'm really keen to get it on the 3D printer. If you have any questions about this toolhead, leave a comment below, and keep up to date with our new tutorials coming out soon, which will be covering over how to use the dual extruder in all sorts of exciting ways.Thanks for watching, guys. Have a great day.