Aidan shares some tips on how to use your Lulzbot Mini and go about your first 3D print. We often find people new to 3D printing overlook the timings of events (such as heating up), the reason for self-calibration, the difference between ABS / PLA, along with some other quirks.
Hello, Aidan from Core Electronics, today I’m going to run you through your first print with the Lulzbot Mini 3-D Printer. So I’ve got the printer here: It’s one of the newer models of the Lulzbot printers: I’ve got one unpackaged and ready to go. If you followed the unboxing guide, it’s all pretty straightforward – probably take you 5-10 minutes and download and install Cura as well because that’s what we’re going to be using to control our printer today. So the first thing you’ll be met with when you install Cura is this screen here. It’s called the Configuration Wizard and you’re just going to run through the steps for your own printer.
00.30 I’ve got the Mini, so I’m going to select ‘the Mini’, and I’ve got the standard tool head – that’s this part here, the extruder part. So I’m going to run through that and click ‘Finish’. Here we go. So now I’ve got the print bed loaded up here. We’re going to load up our STL which is the Rocktopus, and I’ve got that one there. You can download that from Lulzbot if you need to, it should come with your Cura installation, (01.00) and there we go. That’s our visualization of what we’re going to be printing today. So the next step will be to select the filament of what we intend on printing. I’ve got some 3mm ABS filament here; I’ve just got a sky-blue colour. I think it’ll look quite good on the print bed. And the first thing we’re going to is remove this bit of filament, but right now that print head is cold so it’s not going to come out easily. So what we’re going to do is get this up to a temperature where we can pull it out, nice and easy. (01.30) We’re going to replace with the filament we’ve got here and we’re going to start printing. And it’s just as easy as that.
So go into Cura, open up your control panel and let your printer connect. You’ll hear it kick in and there we go, we’ve got all the different controls here. So just a quick run through: if you were to, you could just home your printer with your Home buttons in the corner here, or there are millimetre increments: (02.00) 0.1mm, 10mm or 100mm movements on all the axes on the bed, and you can also extrude and extract filament here, or move your Z-axis up and down. So, they’re all the different settings that we’ve got. I’m going to use 170? C here today, get to get that ABS out of the tool head. So go ahead and type in the temperature in the top box, click set. And you’ll see a little graph there over time that will reflect the temperature of the tool head. (02.35). I think she’s hot enough. I can’t really get to the hinge dial so I’m just going to move the axes across this way. So let’s just move that one across, and there we go. So the idea here is: there are 2 screws. We’re going to put pressure on the screws and with the thumb, pull the idler up and out. So now we have access to this bit of filament here which we can just pull straight out.
03.00 Next step is, you will be getting your Lulzbot Mini in this configuration so we’ll pull the spool holder up, in case you’re wondering and put this spool on and feed [the filament] down in through the feed hole, nice and easy. And just in reverse of what we did before, we’re going to lift it up the eye of the wheel up against the filament, put the pressure on those 2 screws, and pop t back into place.
03.30 So now we’re going to heat this tool head back up and heat it to about 220-230? C for ABS. It’s labeled on our filament roll here. Once we’ve got it up to that temp, we’re going to purge some filament through, until we get a nice, consistent extrusion. It’s just part of the process, and then we should be alright to print. So let’s go ahead and do that - 220?C, set that temp. and we’ll just wait for it to get up.
04.00 So now our tool head’s up to temp. so we’re going to purge some filament through using the control interface with Cura. So if you look, on the far right of that window there’s an extrusion button and we can extrude 10mm at a time by clicking on that button so I’m just going to go ahead and extrude [that]. It usually takes 3-4 clicks of the button and we’ll start seeing a nice, easy extrusion, which is exactly what we’re looking for. (04.30) So we’ll just go through that process now, keeping an eye on it, making sure everything’s working as expected. …. Nearly there. So usually I just extrude a couple of clicks through, just to make sure it’s all good. So we were printing with this blue ABS before, (05.00) so it’s not too big of a deal, but if you were printing with a different colour, you might have to do a couple of extra extrusions and that’s because it’s all welled up in there and you wanted to pass through as much filament as you can. So now we’ve got the tool head up to temp, there’s one thing about ABS: we need to print with a heated plate. So we need to get this up to temp – that’s part of the G code, so we’re not going to worry about right now. One thing I will recommend: for every print you ever do, is just to treat your bed with whatever you need. For ABS, you need a PEI (POLYETHERIMIDE) sheet here. (05.30) It’s not required that we put anything down – it’s going to stick to it no matter what, but I do like to give it a quick wipe down with isopropyl, just to make sure it’s nice and clean before we proceed. So I’ll grab some paper towel and isopropyl and just give it a quick wipe down. You can see it just cleans up any plastic bits you had from previous prints. (06.00) Something to bear in mind for future printing.
So I’m happy with that, and now it’s easy. We’ve got the STL set, we’ve got our printer profile set. What we’re going to do is just click ‘print’. The mini has a start up sequence: it’s going to heat up the tool head and the bed. (06.30) It will then scrub and self-clean its tip. It will then go, on auto, to these 4 conductive pads before it starts printing. So that’s just something that is going to go through the process now. I will give you a quick word about what I’ve done here. I’m using the profiler here HIPS. I know I’ve used ABS here and HIPS in the profile. That’s fine. That profile just defines the temperatures at which the printer needs to heat the heated bed, and the tool head. And so for HIPS and ABS, it’s quite a similar temperature. We’re working with thermoplastics, so as long as it’s above a certain temperature it’s going to extrude. We’ll just let it get up to temperature and then walk you through what’s happening here.
So we’ve got the printer starting up now. It’s just going to retract any filament away so it doesn’t extrude along the self cleaning pad here. (07.30). It’ll drop down (there was quite a vigorous scrub along this back pad).
The reason we have to clean the nozzle is because everyone of those corners is a conductive pad and, our nozzle is the conductor as well. It’s creating a ground point, and it’s leveling the bed here. So we’re going to let that happen. Essentially it’s giving you a nice flat plane to print on which helps a lot with that first level of adhesion.
(08.35. video hyperspeed) So we can see our print is coming down – our Rocktopus is coming along quite nicely there.
Now the difference between our 2 main filament types: we’re using ABS today but sometimes you’ll see PLA is the preferred filament of choice for some people. I want to give you a quick run through the differences between the 2 filaments. That way you can make an informed decision about point. ABS is a plastic derived from fossil fuels and due to that, it is not biodegradable – adds to landfill which isn’t good. It’s also got a higher tensile strength. It can survive in higher temperatures, but it also prints at higher temperatures. And it requires beds to be upwards of 100? Celsius, just so you get that first layer of adhesion. ABS is soluble in acetone and you can do some pretty cool things with acetone and ABS. We’ll do a tutorial about that: (09.30) smoothing your parts with ABS and making them come up nice and glossy.
PLA, on the other hand, is a bioplastic. I think it is derived from corn starch and things like that. It prints at quite a high temperature – 180-200?C – a bit less than ABS. The bed also needs to be only about 45?C with PLA. PLA is soluble in sodium hydroxide but that’s a bit of a dangerous chemical so we don’t really recommend that you smooth the PLA parts with sodium hydroxide. (10.00) Like I said, PLA is a bioplastic, and since it’s derived from biomaterials, it’s also biodegradable. The general rule of thumb is about 6 months-2 years of life in outdoor environments for it to keep the structural integrity of that print. It’s also quite brittle when you print it, so PLA doesn’t have much impact resistance. (10.30) So if you were to strike a PLA print, you could nearly guarantee that it’s going to break. So it’s something to bear in mind.
The big, main difference is that ABS is prone to some warping. Warping happens when the edges of your print cool at a faster rate than the insides of your print. Essentially, you get parts of print coming off the print bed and it can cause all sorts of problems for people who don’t know about it. So ABS is prone to that sort of warping, whereas PLA is almost not prone to any warping whatsoever. (11.00) There are ways around warping; it’s not something that once the plastic does it you can’t fix it. We’ve got a heating closure over in the warehouse which we use for all our prints in ABS and it always works really well. We keep the surrounding temperature at about 40?C and it just holds that temperature and our prints just don’t warp at all. That’s all we need – we don’t need to keep our prints at 100-110?C, whatever. It’s all just about 40?C and it’ll stay flat. Something to bear in mind when you’re printing for the first time, though because the last thing you want is funny shaped prints that don’t seem to be working and you’ll be pulling you hair out no-one knows what’s going on, and that’s the thing you’ll look out for.
(12.00) Another thing about these printers is this PEI sheet: you can see that that first layer went down really easily. The printer knew where it was because of the auto-levelling system and the PEI sheets heated up to about 110?C and because of that, we’ve got that filament layering down nice and easily. It’s going to hold it there, to that bed, through the entirety of the whole print. You’ll see at the end of the print, the print level will move to the back. The PEI will cool down to about 50-60?C, and then when it’s ready, the print bed will move forward to its most forward position. (12.30) Now, if I was standing in front of the printer, it would be quite difficult to get the print off of the back there. That’s done for a reason. We don’t recommend that you get in there and try and take the print off while the bed’s hot. The PEI, at higher temperatures, is actually quite malleable so if you try and prise it off with a knife, you’ll cause some damage to your bed. Lulzbot doesn’t recommend it and we don’t recommend it so better to wait the extra 10 minutes.
(13.00) Now I’ll walk you through the process of getting your print off the bed. Like I was saying before, we have a PEI bed here which makes it very easy for ABS to stick to it, so this is the bad part: sometimes it’s hard to get your prints off the bed. So Lulzbot gives you a little knife that comes with the printer. All the printers have them. What we’re going to do now, is prise our print off the bed. (13.30) You’ll see that one side of the knife has a rounded edge to it. We’re going to lay it down and prise out between each of the legs so that hopefully we can get it to just ‘pop’ off. So we’ll go one leg at a time, trying to not break it because it can be quite brittle at this point. I might have to come around the front and get in there (not the best angle).
(14.00) So, I’m getting underneath the leg here and hopefully I can get the knife there towards the centre of the base and just prise her up. And I’ll do that for every leg and eventually you’ll find it just pops off, like that. So there’s the skirt, part of the first line that went down, to purge any inaccuracies out of the filament. So we’ve printed out first Rocktopus. So thanks for watching, guys. That was our first print with the Lulzbot 3-D mini printer.