Summary

Modelling our Designs in CAD software opens up doors when it comes to producing them, especially using automated manufacturing processes. In this webinar we'll look at the practical process of 3D printing patterns and moulds for composite construction and some key considerations.

00:00 Hey team, Connor here from HPA.
00:01 Welcome to another one of our webinars.
00:04 Today, we're going to be talking about 3D printing molds and also patterns for use in making composite parts.
00:10 So, carbon fiber, fiberglass, Kevlar, whatever we want to use for our composites.
00:15 So, we're going to start off by just talking about what this means and how we can use 3D printing to our advantage to make things easier for ourselves.
00:22 And then we're going to talk about some of the key considerations around using 3D printing for this and then look at a few examples as well.
00:29 To start off, we'll just start kind of at base level.
00:32 For those of you who aren't so familiar with the composite construction techniques, we're just going to talk about what molds and patterns are.
00:40 We'll start with patterns because that kind of comes first in the process.
00:43 Patterns also might be called plugs, bucks, or originals in some cases.
00:49 But basically what this is, is a rigid and also dimensionally accurate representation of the final part.
00:56 And we use that to make our mold.
00:58 So, we use the pattern or the plug to make the mold, and then we use the mold to make the part.
01:04 So, we'll move on to the mold.
01:06 The mold is just a negative of... yeah, it's a negative version of our part that we can use to make the part.
01:16 So, if we talk about 3D printed patterns, what's going to be important there is the material that we use and the surface, be it the surface finish or kind of how that surface interacts with the mold that we're making.
01:33 Typically, so if we think about a 3D printed part, be it from FDM, which is our typical style of 3D printing, or SLA from resin printing or something like that, we want to make sure that the material doesn't really absorb whatever goes on top of it.
01:53 Because if we try to laminate straight on it and use resins and so on, that will be absorbed into the surface.
01:59 And what we'll get is the part or the mold that we're trying to make then bonding to the pattern, and we won't be able to separate them.
02:07 So, typically, the approach to this is using a release agent.
02:11 But there's a few steps that we need to do before that, because of course, the release agent can just soak into the part as well.
02:17 So, again, the material we use and the surface of that material is really important.
02:22 Even if we're using something like SLA resin printing here, and we're post curing it, it's still really hard to get a perfect cure some of the time.
02:33 So, we'll usually turn to something like a mold sealer, which we'd probably use anyway in most cases when we're starting with a new pattern or mold.
02:43 But also what we can do is apply other coatings to it to seal it up.
02:49 So, I've got a few images here of potential products.
02:54 One approach, an approach that we take pretty regularly is to use a product called Duratec.
03:00 So, Duratec is what we refer to as a pattern coat primer.
03:04 So, that basically means we can 3D print our mold out of a range of different materials, and then we can just coat it in this.
03:11 And this is designed specifically for this job.
03:14 So, what it's going to do is it's going to seal the surface really nicely.
03:17 And it's also going to mean that we can polish it to quite a high level finish.
03:24 So, we can sand it up and then move on to cutting and polishing it.
03:28 Because the surface finish of our pattern is going to then be transferred to that of our mold.
03:33 And then that's going to kind of be the surface finish of our part.
03:36 And of course, between each of those steps, we can do more sanding and polishing and so on.
03:41 But the better we make it from the start, the better it's going to be at the end.
03:45 So, we can use Duratec to seal it up.
03:47 And another approach is using a coating resin.
03:51 And this is a really kind of hobbyist, basic one designed specifically for 3D prints.
03:56 More with FDM printing to try to level out those layer lines.
04:01 But it's just essentially an epoxy coating resin.
04:04 And we can paint that on and then that should give us a nice sealed surface.
04:09 I'll just jump back to my notes here.
04:12 So, from there, after we seal it up, we can then probably on top of that use a mold sealer and then use our release agent as well.
04:25 And we've got a nice hard surface that we can use to pull off for a composite mold or a composite part.
04:32 The alternative to some of this or a possible release agent that we might use, but often this is kind of makes things a little bit easier, is what's called PVA parting film.
04:43 So, I have PVA here, a photo of it.
04:47 So, this is basically a form of release agent, not to be confused with PVA glue, because naturally they work kind of opposite to each other.
04:55 But this is something that we can spray or brush onto the surface of a part.
05:00 And it gives us a really sure release, I guess.
05:03 It's quite user-friendly or safe to use when we're a little bit worried about the release.
05:12 If we're using materials we're not too certain they're going to release well, we'll use PVA parting film.
05:17 The downside of it... Hey guys, sorry about that.
05:20 Just a bit of technical difficulties.
05:21 We'll just pick up where we left off.
05:23 So, what we're discussing is after we've sealed up our pattern, applying mould seal as release agents.
05:29 And an alternative or a possible release agent we might use is this PVA parting film.
05:37 And basically it gives us a really easy release if we're a little bit worried about the two materials that we're working with and if they're going to kind of bond together.
05:45 PVA parting film is kind of a little bit of a safety net.
05:49 The downside, as I was just mentioning for it, is that after we release it, we need to basically wash it off the surface of our part and we can just use water for that.
05:58 But it will leave a little bit of kind of swirling and everything on the surfaces, like the mould surface or the part surface.
06:05 And probably what that's going to mean is we just need to spend a little bit more time after that step doing a bit more polishing to get that out.
06:14 So, PVA parting film I find is a really good option if we're working with 3D printed moulds or patterns or just anything for that matter that we're unsure of the actual surface prep that's been done or the materials or coatings that have been used.
06:28 The other thing we need to consider if we're talking about 3D printed patterns is the material that we use and the temperature that that needs to be able to withstand.
06:39 So, if we plan on doing anything where we're kind of using an epoxy resin or something that's going to have quite a high exotherm, that temperature could get to 100 plus degrees celsius and obviously the surface or the material of our pattern or our 3D printed part needs to be able to withstand that.
07:00 Same goes if we're going to post cure or do any curing in an oven, if we plan on baking it and the part, the pattern is going to be exposed to that temperature, then we need to use a material, be it a resin or a FDM filament, that is going to stand up to that.
07:19 The other thing when we're talking about patterns is we can include features in them if we're 3D printing them without having to kind of make them by hand, we can get the 3D printer to make it for us.
07:30 Features like flanges and fixing or locating features as well.
07:35 We'll have a little bit more of a look into that soon if you're unfamiliar.
07:40 And as I mentioned throughout this, you can use FDM, which is like your normal style of 3D printing, building up the layer lines like a bamboo lab or a creality kind of unit, or you can use SLA, which is resin 3D printing, where we're using a photopolymer resin and curing it layer by layer as well.
08:01 Again, we'll have a bit more of a look at that soon.
08:04 So, moving on from there, what if we went straight to 3D printing the mold itself? Well, the material that we use and the surface is still important, basically for all the same reasons that we've just mentioned.
08:18 And we'll probably want to use something like PVA as a release film as well, although if we're really sure about, you know, we use a primer on the surface, seal it up nicely and then use release agents, that's a possibility as well.
08:34 But it just takes a bit more work and maybe it's a little bit less of a sure thing.
08:40 Same thing, it needs to be rigid, obviously, as our part cures, we don't want anything flexing or moving around.
08:47 So, that's really important, but typically it also needs to be quite tough where the pattern doesn't need to be as tough.
08:54 Obviously, we don't want to break something if it's really brittle while we're working on it, but the reality is a pattern only really needs to be used once to create a mold, but usually a mold needs to be used multiple times if we want to create multiple parts out of it rather than just a one-off.
09:12 So, typically the material that we use, we'd want it to be tougher, basically, and plastics used in FDM are pretty tough, whereas resins used in SLA are typically a lot more brittle.
09:30 Again, the surface finish is going to be really important because that's going to be transferred over to our part.
09:36 We can, of course, coat it and then sand it and polish it, but this is all work that you have to consider doing.
09:45 And again, we can also include features in the 3D print of the mold used in the construction of the part, like the flanges and so on.
09:54 Again, we'll look at that a little bit more soon.
09:57 Now, one of the questions you might be having, why not just use or just 3D print the mold in any case if we can just skip the pattern-making step altogether and jump straight to the mold itself? And that's a good question.
10:15 And of course, in some cases, like something we're going to look at in just a moment, we absolutely can do that.
10:20 But in other cases, like using high-temperature molds where we're going to expose these molds and the parts to cure them at high temperatures, we need to first make a pattern and then make the parts.
10:36 So, I'm going to explain that a little bit more.
10:38 So, basically, with high-temperature composite construction, things like using autoclaves or out -of-autoclave for curing prepreg materials that need heat to activate the kind of curing process, yeah, it's going to be exposed to heat.
10:56 So, every material that is exposed to that heat needs to be able to withstand that heat.
11:02 So, a lot of what we think about here is called CTE.
11:05 So, that's coefficient of thermal expansion.
11:08 And basically, what that means is how much the part or the material expands or changes size when it's exposed to heat.
11:17 Thermal expansion of plastics and a lot of the metals that we use, like aluminum, are actually quite bad.
11:25 And by that, I mean they expand a lot under heat, where the CTE of carbon fiber is very low.
11:33 So, basically, if we are making a carbon fiber part in a plastic mold and we expose it to heat, the mold will grow quite a lot where the carbon fiber won't grow quite a lot.
11:51 And basically, what that ends up meaning is we get dimensional inaccuracies and we don't kind of get this good consolidation of the part in the mold, and we end up with things like pre -release happening where the part starts to try to release from the mold before it's actually fully cured, and we end up with usually a useless part.
12:09 So, if we talk about the pre-preg process and nothing to do with 3D printing here, typically, if we're using an autoclave to cure parts, what we end up doing, the whole process of making the pattern, the mold, and then the part, looks a little bit like this.
12:26 We'll use epoxy tooling board to make a pattern.
12:30 And I actually have a bit of an image here that I can show you.
12:33 So, this is an epoxy tooling board pattern for a bucket seat, a race seat.
12:41 And then we'll use a tooling pre-preg.
12:48 So, it's a carbon fiber pre-preg material, so pre -impregnated with the resin, that we can make the mold out of.
12:57 So, the mold itself will also be made out of carbon fiber, and then we can make the final part out of carbon fiber.
13:03 There's a few things to kind of consider in that process as we go.
13:07 So, the tooling pre-preg itself is actually what's called an LTC, so a low temperature carbon.
13:15 And that basically needs a low temperature initial cure to just kind of solidify and get its shape.
13:24 So, that might be something around like 60 degrees Celsius or somewhere around that range.
13:30 So, basically, if we put that in the oven or the autoclave, the actual thermal stresses and the expansion of the epoxy tooling board, which is essentially just a plastic tooling board, is relatively minor because it's only at kind of 60 degrees.
13:47 So, then we can do that initial cure and we can demold the carbon tool off it.
13:53 And then basically we can, you know, the pattern doesn't need to be used anymore, but we can then transfer that carbon tool again back into the oven or the autoclave, and we can do a post-cure on it freestanding so it's not on the pattern anymore.
14:11 And what that means is we basically slowly ramp up the temperature and kind of cure it at a higher temperature.
14:18 And what that does is it chases the TG or the glass transition temperature for that carbon up higher.
14:26 So, as that TG gets higher, basically, the part can then withstand more heat.
14:35 And then we can use that, sorry, that mold can withstand more heat.
14:39 And then we can actually use that mold to make a composite, sorry, a part out of a component prepreg.
14:48 And that component prepreg at that point could be HTC or MTC, medium temperature carbon or high temperature carbon, which needs to be cured at a higher temperature, but then can withstand even higher temperatures after that.
15:01 So, that gives you a little bit idea about that process.
15:04 And what we end up with is this carbon tool that will expand at the same rate or very similar rate to the carbon part inside it.
15:15 So, we get something that's very stiff and rigid and good as a tool, but it also, we end up with good dimensional accuracy in the part and it just cures a lot better.
15:25 And that's really important.
15:27 I've just got another photo here for really large scale parts, typically not something that we're going to 3D print in all honesty, but these are, you know, wings of an aircraft of some sort, and these are carbon fiber tooling, carbon fiber molds.
15:42 And on something like this, it's obviously really critical that the dimensional accuracy is really good and they don't expand and grow during that curing cycle.
15:53 Because if you think about that expansion over such a long length, then that's going to end up with, if it's a small percentage, it's still quite a big value in terms of the amount that it changes.
16:04 So, you could end up with something, you know, that's three meters long that only kind of changes by a millimeter or so.
16:12 So, you're in kind of good tolerance range there.
16:15 So, that's basically why all of this is done.
16:17 So, let's wrap that back a little bit to the actual 3D printing side of this, which is basically an alternative or cheaper process that we're looking at anyway.
16:29 So, basically what we're going to do is we're going to 3D print a pattern that's going to be plastic, which has... we're typically going to be plastic, which has a poor CTE value.
16:40 But then we can use that to make a high temperature mold using perhaps fiberglass as a little bit more of a cheaper alternative, and high temperature resins that only need a low temperature initial cure.
16:55 So, I have a few other products, photos of here, bear with me for a second.
17:02 So, we could use a high temperature tooling gel coat on the surface to make that mold, and then a high temperature tooling resin there.
17:10 These are epoxies.
17:11 If we're using them with fiberglass, then we'll also use a powder bound fiberglass, but I'm getting a little bit off track there.
17:19 Just that with an epoxy, you need to use a powder bound matte rather than an emulsion bound matte, because epoxy won't dissolve the emulsion binder.
17:27 Anyway, we'll keep on topic, but basically then we can make this high temperature fiberglass mold, we can demold it off the pattern, and then we can cook that fiberglass mold at a higher temperature, and then raise the Tg of it, so then we can make perhaps an out of autoclave prepreg part in an oven using carbon fiber, and it'll probably be a smaller part where dimensional accuracy is not so important, but that composite mold will not be too bad anyway compared to something like an original plastic part, for example.
18:04 So, that's kind of basically why you wouldn't always just 3D print a mold, and maybe you'd 3D print a pattern instead.
18:12 On that note, we're going to look at that kind of temperature considerations around this stuff more in more depth in a coming webinar, so don't stress too much about that for now.
18:24 Our focus is just on the 3D printing side of things, and if you have any questions that are coming up during this, just feel free to ask them in the chat, and I'll do my best to answer them at the end.
18:35 All right, so let's talk about some key considerations when it actually comes to 3D printing patterns or molds, and one of those is going to be flanges.
18:47 So, flanges are basically the flat sections around the mold cavity that extend out, and we use them for various things.
18:55 So,metimes they add stiffness.
18:57 We can use them for locating and fixing sections together.
19:01 It might just be a part that we can wedge under and pop the actual carbon fiber part and release it out of the mold.
19:09 And it's also in some cases used if we're doing a tool-sealed vacuum bag, so we're sealing it to the tool itself.
19:19 We can seal it to that flange.
19:21 It gives us a nice flat surface there.
19:26 So, when we get to the examples, we'll look a little bit more at that.
19:29 Trim allowance is something else we can kind of design into it.
19:33 So, basically, I will show you this again in just a moment, but if we just look under the overhead camera here, this is a 3D printed mold.
19:49 And you can see on this, I have this kind of hard edge over here where we've got an extension of the part, but it changes angles.
19:59 And what that gives me is a clear line that when the part comes out, which is the part here, I can cut around.
20:07 And it also gives me just a bit of extra material I can take off the part as well.
20:12 So, that's an example of a trim allowance.
20:14 And then on the pattern here as well, you can see down the bottom, I've kind of done a similar thing like that.
20:22 So, added a bit of trim allowance and then a bit of trim allowance here.
20:26 But I'm going to come back to these in just a moment.
20:29 Locating and fixing features.
20:31 So, this is really if we're going to be using a mold with multiple pieces, like a split mold, because we need to split it open in order to remove the part from it.
20:42 We can add little locating pins to it so the two halves of the mold align really well on the flanges.
20:51 We can add fixing features, whether that's just going to be holes or something like that.
20:56 So, we can locate those two parts together with some hardware.
21:00 Draft angles.
21:03 So, if you're not familiar with draft, what that means is if we look into our cavity, the walls that extend kind of away from us, we want them to be opened up to be facing us a little bit.
21:15 Because that means that when we release the part, it's not going to be bound up in there.
21:19 So, if the walls of the cavity are facing away from us, that's negative draft and we're never going to be able to basically release the part from the mold or the mold from the pattern.
21:32 And if we have positive draft, it's opened up towards us and it's just going to be easier and easier to release the part, essentially.
21:41 And then the other thing to consider, pass at, is the print orientation.
21:47 And that kind of comes into play with FDM especially.
21:54 So, this is an FDM printed mold here, and this is actually printed in kind of the wrong orientation here, where the layer lines are going in this direction.
22:05 So, the part was printed on the bed like this, essentially, and the part's stacking up the layer lines like this.
22:11 And what that means, and I know this is quite small, I printed this just before we came over to the studio here, and it looked a lot larger in CAD.
22:22 I'll just leave it at that.
22:24 But basically, you should be able to see here that these kind of bumps on this is what the layer lines of the mold look like.
22:34 And if that's standing up vertically like that, and then we have the part and that cures into it, we're going to get these kind of negatives of the layer lines.
22:47 And then as you try to separate them, so they're trying to slide this way relative to each other, it's just going to hook in there and make it quite difficult to separate from one another, because it's going to be trying to pull up like that, essentially.
23:02 Now, if we have draft angle on that, that means that this wall is essentially going to lean over a little bit like that, and then the pull direction is going to be a little bit more in this direction, and it'll pull up a bit easier.
23:18 And basically, what we get there, what we find there is if we have anything over about five degrees of draft, we're not really going to have a problem with that print orientation anyway.
23:30 And another thing to consider is the actual layer height as well.
23:34 So, typically, when I print 3D print with FDM a mold, I'm going to make that layer height as low as possible.
23:43 So, something like 0.08 or 0.12, maybe compared to the typical 0.2 millimeter layer height.
23:52 So, I'm just going to make it as fine as possible.
23:54 That's going to help the surface finish, but it's also going to help kind of limit this issue here.
24:00 And of course, I'm going to make sure I've got draft on those.
24:03 But the better thing to do would just be orientate this part so as it's printed on the print bed, you print it vertically like this.
24:11 And that's the way that I actually made the parts that came out of this, of another mold similar to this.
24:17 And what that means is that the layer lines are kind of coming up the walls like this.
24:22 So, rather than being like that, now they're like that.
24:26 And as the part pulls out of those layer lines, it's just moving in this direction here, straight up, rather than trying to slide against each other.
24:38 So, hopefully that makes a little bit of sense there.
24:40 And yeah, typically print it like that and it just makes releasing the part a little bit better and probably makes the surface finish a bit better as well.
24:50 Cool.
24:51 So, with that out of the way, I just want to show you a few examples and some of the considerations I talked about then will make a little bit more sense as we kind of go through this.
25:02 Before we get started on that, I'm just going to show you this CAD model here because they're both basically from this CAD model.
25:10 So, this is a carbon fiber mirror that I've designed, and it's going to fit on the side of our SR86 there.
25:18 It's kind of GT3 RSR Porsche kind of style or inspired, I guess.
25:25 It's going to have an aluminum 3D printed base plate here, and the mirror itself is just a solid carbon bit, and then it's going to have a swivel for the mirror.
25:35 It should be a nice lightweight solution.
25:37 So, if I just hide that, we can kind of look inside it and see a little bit more about the design.
25:47 And then all of the molds for this or the patterns are going to be 3D printed anyway.
25:54 So, let me just find where I'm at.
26:05 So, inside this, it doesn't look great as well, bear with me for just a second.
26:14 All right, so inside this, I just have this little base pad here, and there's a little swivel that sits on that, and then that all supports the mirror.
26:22 And that's essentially what this mold here is used to make.
26:29 And rather than making those out of prepreg, I'm just taking a kind of easier route, and I'm hand laminating or doing a wet layup of those and then vacuum bagging those.
26:38 So, with that in mind, let's talk about the features of this mold.
26:42 And I can also just bring that up here as well.
26:50 Sorry, seems like we're having a bit more problems with the screen share thing, so we'll be back in just a moment when we figure it out.
26:55 Hey guys, sorry about that.
26:57 We'll jump straight back into it.
26:59 So, in the CAD model, this is the little mold that I've designed here.
27:03 And again, we're designing this so we can hand laminate or wet lay these parts and then vacuum bag the whole thing.
27:09 So, things to consider here about that, I've duplicated it so I can do both of them at the same time in the same mold.
27:16 And then also just rounded all the edges so as we vacuum bag it, there's no problem that the mold or anything is going to punch at the bag as well.
27:26 It just makes it all a little bit easy, has a bit of a flange on it and that trim allowance that we talked about before.
27:33 And then we can also do a bit of a draft analysis.
27:36 So, if I go here, draft analysis in CAD, select the body and then select the direction, we can clearly see at two degrees that is completely fine.
27:49 And if I even up that to about five degrees, we've got more than five degree draft on all those mold surfaces there.
27:58 So, we know, minus a little bit there just on the edge, but we know that even if we print this in the wrong kind of layer orientation, it's going to be kind of fine there in terms of the release.
28:12 So, yeah, that's essentially the mold design for that.
28:17 Bear with me while my computer loads.
28:20 And then we can see the actual parts that are made out of that.
28:24 And these are just, you know, really cheap and easy way to make some carbon fiber parts.
28:30 These still need a little bit more finishing up, but super light, really well consolidated, get into all the details and it'll be perfectly fine from with inside the mirrors where you won't be able to see it anyway, other way.
28:47 And you can see how those two just fit into that mold.
28:52 And then, yeah, we popped those out and there you have it.
28:57 So, that's a bit of an idea about a 3D printed mold that we use for hand lap and vacuum bagging.
29:05 And all I did was applied a PVA release agent to this exactly how it is.
29:10 And if you're curious, the material I used for this is PETG, which tends to provide a pretty good release anyway without too much extra work.
29:21 PETG works really well.
29:23 It's relatively cheap and easy to print with.
29:26 So, just a really fast 3D printed mold there for some basic parts.
29:34 Let's jump back onto my computer here and we'll have a look at the rest of the plan for making these.
29:44 So, as you can see there, we've got the kind of mirror design up again.
29:52 And then basically, we want to design a mold that can make this part and then design a pattern so we can make that mold, which is essentially just the original part.
30:04 So, this is the original plan and I will be completely transparent in that I'm changing this plan a little bit because it's probably just going to make my life a little bit difficult.
30:13 So, we're going to change it a bit and then basically do this again just a slightly different way.
30:19 But all of this is still completely relevant.
30:24 So, if we look at the actual mold bodies, essentially, the plan was to make it in these three sections here that you can see in blue, red, and green.
30:34 And that was going to be a three-piece split mold.
30:38 And from that, I'd be able to make that part and kind of do an internal vacuum bag down here.
30:45 And for those of you familiar with this process, I was going to make this with prepreg as well.
30:50 I'd have to have, you know, a bit of a lap joint over here.
30:54 And you can see that this is just going to be really small and make that very difficult.
30:58 Could use something like an intensifier.
31:01 But again, we're just getting off track a little bit here.
31:04 So, this is the idea for making the pattern... sorry, the mold.
31:09 And then from that, we need to kind of make a pattern to be able to make that mold.
31:17 And that could just be, you know, the CAD model of the original part, and it is very similar to that.
31:23 But that's actually what we have here.
31:25 And these were all resin printed.
31:28 So, let's just have a little look.
31:31 Turn some of these parts on.
31:38 Okay.
31:39 And we'll get rid of the mold.
31:41 So, we'll start with this part here.
31:47 So, this is essentially the design for the mirror again.
31:51 I've added a little extension here and a bit of a chamfer.
31:55 And that's going to give us a trim allowance.
31:57 So, a really clear trim line and some excess material that we can remove.
32:01 I've thickened it up quite a lot and added all this kind of ribbing structure in here to make it really nice and rigid.
32:08 So, it's not going to flex or move or do anything while I'm making the part... or the mold, sorry.
32:14 And then that's essentially one part of the pattern.
32:17 And then I've designed a few other parts as well.
32:22 So, these are just designed to be able to clip on and basically provide that flange so we can lay up our fiberglass mold across the top side of this flange here in the first step.
32:36 And then we'll be able to remove this printed part here and then move on from there.
32:40 But it's probably just going to be easier if I show you this under the overhead on the actual part.
32:46 So, this is just the part as it kind of came off the printer.
32:50 I haven't tidied up the surface finish or anything yet, but this is a resin printed part.
32:57 So, that's that part.
32:58 And then we have this little flange that just clips on there.
33:05 Now, I'd be able to put like a filleting wax or something around here.
33:09 This would all be Duratect first.
33:10 Like I said, a pad and coat primer, seal it up really nicely.
33:15 And then we would apply a release agent to it, possibly PVA, and then apply a gel coat, laminate our fiberglass mold onto the back of it.
33:25 And then we would just be able to remove this flange like that and then move on to the next step, which would be adding this part onto it.
33:37 It's just going to clip in nicely there, hopefully.
33:45 It probably just needs a little bit tidying up and sanding.
33:49 That's in there pretty good now.
33:51 So, then that would clip on there under that top surface and we could lay out the second side against these flanges here.
33:58 And we could have little locating features on here too, but I'd probably just use a small little lump of filleting wax there so they locate nicely.
34:07 And then finally, we could lay up the third side of the mold here and we'd have a nice three -piece split mold.
34:15 Now,, for those of you, again, who are familiar with this and thinking that looks like it's going to be really hard, you're completely right.
34:21 Trying to remove this section of the mold from here and make this all work, I've decided is going to be really hard and not probably work that great without breaking things.
34:31 So, I am changing this design a little bit.
34:33 But again, it still gives you an idea about the features that I've added to this to make a 3D -printed pattern to allow me to make a high -temperature mold.
34:43 For those of you curious as well, I just have... this is just using our Elegoo Saturn 4 Ultra printer, which I've got shown here, and a resin which I think is going to be pretty good for this is this Frozen Loctite Collab Onyx Pro 410, which is a rigid resin.
35:03 So, it's nice and stiff and it's really good for making patterns like this.
35:07 But again, I will just be coating it with a Duratect primer like that before I did anything so I could seal it up nice, give it a good surface finish and go from there.
35:19 So, anyway, with that covered, that's a few examples of how we're working on this and something we'll hopefully be able to show you guys more in the future as well.
35:29 Again,, I am changing this design a little bit, so it's going to look a little bit different when we actually get to it.
35:35 But I'll wrap up there and I'll have a look at the questions and see if I can help.
35:50 All right.
35:50 The Ricky John, do you need a factor in the added thickness for things like the Duratect coatings, release agents, etc.
35:57 Into the 3D model to maintain dimensional accuracy? Yeah, absolutely.
36:01 Something like Duratect, I think you spray it on in about 0.4mm thickness, so you can definitely add that.
36:10 Obviously, by the time you spray it on and then you sand a little bit off, it's going to be pretty minor, but it is something to keep in mind if you do a couple of coats, for example.
36:19 It just depends how much finishing work you're going to do on it.
36:22 Release agents themselves, typically the release agent wax, which I can show you here, like this Meguiar's Mirror Glaze or something like Chemlease as well, like a chemical release agent, is going to have a negligible thickness.
36:41 It's really just a haze on the surface.
36:45 So, that's not really going to factor into it too much.
36:47 But absolutely, if you're adding coatings to it after the fact, like paints or primers, then it is something that you should consider, sometimes more than others, and it really depends on what you're working on.
37:01 So, hopefully that answers that.
37:06 All right, no more questions.
37:08 So, hopefully that's given you guys some insight into how you can use 3D printing to make some composite parts for your project cars, or to make molds for some composite parts for your project cars.
37:21 And yeah, we'll wrap up there and we'll be back next week with another webinar for you guys.
37:25 So, thanks for watching.