All right guys, so one of the most common problems that we hear about when we're talking about 3D printing is warping, and I think it's really important to understand what warping is before we try and fix it. Warping is caused during your 3D print. As the plastic cools, it changes shape. Oftentimes, the outer reaches of a 3D model are pulled upward and inward toward the centre of the print, peeling away from the heated bed. If you aren't aware of warping, you'll probably think there's actually something wrong with your printer, tool head, or filament. There's nothing wrong with it; that's just one of the properties of your filament. You won't be able to address this problem without fixing the underlying cause, which is usually caused by cold drafts or something similar heating your print while it's printing and removing heat from it.

Let's talk about temperature stability, bed adhesion, and warping. What we're going to do is take a look at a basic model and see where warping is likely to occur. I'm going to assume that you have a heated bed at least, and having an auto-leveling bed is an even better thing to have. The first layer being uniform and adhering to the bed is absolutely essential, especially with ABS that warps quite a bit. Let's take a look at an ABS model that I've got here that actually warped quite badly. You've got some images to the left of this video on the website, and you'll be able to see quite clearly what the go is there. I've got two versions of the same model here. One version was printed with the exact same layer heights and settings but in PLA. The green one is our Polylite PLA print, and the blue one is a sky-blue ABS print, printed at 0.15 millimetres. It's essentially the exact same STL model except for a few little alterations, but it's a good test to show you the difference between the two plastic types.

Let's have a look at this one. I'll stand this one up straight. You can probably see all these artifacts on the edge of my print, and you might even think that that's just like a bubbling print. What's actually happening is this print started warping up, and as it was warping up, the tool head was traveling over the print. It wasn't extruding in a flat, uniform layer but more like this bubbled, really terrible-looking layer here. You can see that it happened the most in this corner here. There was a little bit over in this corner, and these two corners were actually fine. I had this one printing if you were looking front onto your bed like this, and you can imagine this front side of your printer being a lot cooler than, say, the back area that's protected by the casing of your printer. That is a pretty good example of what warping is and what it looks like. You will see it in all sorts of models; usually, the larger the surface area, the more likely it is to warp.

There are a few things that we can actually do within Cura to try and minimize warping. If those things aren't working, you might consider purchasing a heated enclosure. That's something that can go around your printer and prevent cool drafts of air from going over your printer, as well as trap in a bit of heat and keep your print nice and warm. Alternatively, you can do what I did and swap over to a poly-light PLA print or any sort of print that doesn't warp. PLA is a really good one for it. If we were to do a little side-by-side, you can see there's a massive difference in print quality between those two. Alright, so let's jump over to Cura and take a look at some of the things that we can change to help with warping.

By default, we would be in the quick print menu of our filament, and being in ABS, this is just a standard view of that. We can actually print brims just by default; we can add those in. Like we've seen in the past, they are just a flat model, a flat layer of plastic at the edge of your model. Let's just take a quick look at something that will be... By default, we would be in this part of the Cura interface, just loading in the model and being in the quick print view. To alter the settings that we need to alter, we need to go into the full settings. Go right ahead and jump into that, copying over the correct profile. I'm just on a standard ABS profile for Village Plastics ABS, which tends to work really well with our ABS that we sell in the store.

Taking a look here, we can see that we've got things like layer height that we can adjust—not really going to help us with warping. What we want to do is drop right down and go to our platform adhesion type. As the print cools, it tends to peel away, so what we can do is increase the surface area with layers that aren't necessarily crucial to our print by adding a brim. That's one thing that you can do. You can also add a raft, which can help out. Adding a brim is as simple as that. You can click on this expert button here, and it can add in extra layers of brim. Say we put 15 in, and we can quickly look at what that's going to look like on the bed by visualizing that with the layers view.

You can see now in this print, we were at risk on the front right-hand side. Looking front on to our model, this is the exact model here. On the front right-hand side is this area here, and now I can see with those extra brims, it's going to go and help it stick to the bed quite a bit, as you can see. So that's one thing that we can do. Another thing that we can do is make sure that our bed is heated up at the right temperature for our filament. We've got a heated bed on these printers; you've probably got a heated bed on your printers. They come pretty standard like that now. You really want to make sure that you're keeping your bed temp up around past the glass transition temp of your filament. That's when all the thermal changes start happening. We haven't really covered glass transition temp, but essentially it's just a temperature point of your filament or plastic or any sort of material that has one where it starts going from a solid material to a soft and malleable material.

If we try and keep our print bed at that temperature of the malleable state, we can do our best to try and prevent it from shrinking back into its solid form, so to speak. The brims are a big important one, so is the bed temperature. Also, printing at the right temperature—not really specifically for warping but always very important to make sure you've got that dialled in as best as possible. The next thing we can do is actually go ahead and grab a heated enclosure. There are a few things that you can do for a heated enclosure. What we've done is gone and made our own. Essentially, we went down to Bunnings and grabbed a few bits and pieces of acrylic and some pine and just whipped up a pretty practical-looking enclosure. But we now have available some heated enclosures from LulzBot for their mini printers.

Now, obviously, if you are not using a LulzBot printer, this wouldn't really apply to you, but this is essentially the idea of an enclosure. You can see that it's just essentially covering up all the air gaps in your printer and helps to just really trap in the heat. Like I've said in the past, once I got this enclosure for our printers, ABS warping issues were seriously reduced. It became very easy to start printing larger models with ABS without fail. So that's pretty much warping in a nutshell. If you want to minimize your warping, go ahead and follow those simple steps of adding brims, making sure your bed temperature is right, maybe grab an enclosure if you don't have one. Finally, if you've done all those things and the model just seems destined to fail, you can try doing some things in your design file, which we'll get into later in the 3D modeling section. By changing little parts of your model, like corners and stuff, you can help the amount of warping that happens.