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Complete Lure Design Course – Making 3D Printed Crank Bait Lips

Complete Lure Design Course - Making 3D Printed Crank Bait Lips 1

For far too long, the home-base lure maker has been really saddled with subpar options for crankbait lips. When you look at commercially available lures, their lips aren’t flat, they’re almost always concave and have a curve in the back. I don’t know if this effects performance as much as it does strength, you just have extra material there. So today I’m going to show you how to design these in Fusion 360 and print them out on a 3D printer. Let’s do this!

Setting Up Parameters

All right, we’re going to start with a lure body I’ve already made before. I really like this bait and I want to get back to it and finish it and put a lip on it so I’m going to walk you through the whole process. We’re going to start off with some parameters because everything should have parameters. So if you look at this lure, it’s about 20 millimeters in width at the front where I’m going to put my lip. I’m going to put my lip roughly in this section, it’s a wake bait lip so it’s going to be pretty vertical, and I’ll put a bit of an angle on it. So I already have a pilot hole here for my screw eye, as I mentioned I already designed this bait before and I’ve gone down this path so you should make the lip, then do your pilot hole through the lip to secure everything in place. You can’t really get a screw eye through cured resin, it’s just not strong enough to screw eyes into. So what you want to do is, if you can, make your pilot holes after you’ve positioned your crankbait lip. But, in this case, we’re going to fudge it. So let’s put in some parameters by clicking modify and go to change parameters.

What we want to do is change our lip top width to 20 millimeters. Again, we can adjust these later after we get some things in place. We’re going to do lip max width and I’m going to do a ratio just like a lure I already have so if I measure the top here, I’m at 9.91 and at its widest point it’s 15.7. For the lip max width we’re going to take the lip top width and multiply that by putting at asterisk and 1.5 because that’s roughly what we were before. Let’s add our lip height, this one I’m struggling with. I’m not exactly sure because this one is a lot smaller than the lure I got, it’s 13.5 so it’s slightly smaller than the width. So let’s do that then let’s do some more math because math is fun. If we do lip max width multiple it by 1.1 so it’s 10x bigger than the max width, that’s how high my lip is going to be. To be clear, we’re talking about the lip height that’s outside of the body. We’re going to be handling the inside of the body differently.

Defining the Lip Shape with a Sketch

So, we’re going to draw on this front plane here and I actually don’t need my body right now, it’s only going to get in the way. I’m going to make a sketch here and draw this line down the center. We’re going to design half and then we’re going to marry it over. So, this is going to be my lip height there and that’s a tough thing to accomplish. Then we’re going to draw another line here and that’s my lip top width, and we want to divide that by two because, again, we’re only doing half.

I’m going to draw another line and I’m going to make this a construction line because it’s not going to be part of the actual diagram, and this is my lip max width. Now one thing we can do here is we can use our top width to calculate where that max width comes in vertically. We’re going to hit the D key for dimension, and we’re going to click our center button and come all the way out and do x0.85. This is 85 of the way down the lip, it gets to its widest point and again, we can adjust these later.

Now we want to connect these segments with a spline. I click the point spline, and click a couple of places then click the checkmark and hit the escape key. I want this to be a horizontal vertical constraint because I want to make sure I come in flat across the bottom. I put this in a horizontal vertical constraint which makes this a weird looking lip. I see where I screwed up, but if you also happen to see where I screwed up leave it in the comments.

creating bait lips in fusion 360

So here’s where I screwed up. See this dimension right here, the lip max width, we didn’t divide by two since we’re only building half. Once I divide, it looks a lot better. So now, getting this guy down where he was before, and I want to make him horizontal vertical too. Then we can just mess with these constraints and I can strain the two points there instead of the line and that’s why it wasn’t letter me adjust the distance there.

So now we’re going to properly sketch these in proper dimensions to get our fully dimensioned sketch. I did forget to add a parameter, let’s go at it now. The parameter I forgot to add was how thick we want the top of the lip to be. We’re going to call that lip top thickness because we’re super original. Let’s make it 6 and I don’t really have a reason for that. All we need to do now is draw the very top of the lip where it’s going to enter our lower body. We’re going to make a sketch on top here and we’re going to draw another line. This is the lip top width which is about 2. Let’s not make that mistake again, this is my top lip thickness.

Now you have a choice, you can just make this kind of squared off as a rectangle or you can introduce a skeg keel. Let me show you, lets take a quick look at a commercial lip. You’ll notice that it is not flat at all, they almost always have a bow back here and I don’t know if that impacts performance or it it’s just to make it sturdier. I do know it makes it sturdier for sure because you get a lot more material here and you obviously get a much better connection to the body. That’s really what we want to try and bring to the home lure, to have high quality and provide excellent action.

So let’s see how we do that. I’ll come back to the middle here and I’ll make this my lip top width. If I come over here, I’ll just do lip top thickness and I’m going to multiply it x0.80 so it reduces it by 20% roughly making this line 80% as long as the other. Then we will just take our old friend, fit point spline, connect these two and mess with them until they’re at a place we’re happy with. We’ll make that horizontal vertical, we’ll actually drag it out pretty far and that this one back in slightly again. So I’m going to hit the D key here and we’re going to zoom in to make this a lot easier. Make sure we’re selecting this handle and click this line which will give me an angle that we’re going to make 47. We’re going to dimension these bad boys and we’ll make that 3.8. Now we’re fully dimensioned and we’ll finish sketch. So now we want to bring back our other sketch and you can see I now have this profile.

Loft and Mirror to Create the Form

Now we just want to loft these guys so I’m going to create a loft. I’m going to scroll around here, take out the back and I’m going to select this and this and you can see now you instantly get a pretty awesome lure shape. We can leave a new body, we don’t need any rails. Let me show you one thing you can do though with this second profile. In this second profile, instead of connected we can do direction and you can add a lot more body down the whole length of the lower lip and you can adjust that just by moving this and it really impacts the side view. You can see how it’s making this thicker or thinner depending on how far I pull. I’m just going to eyeball it and keep it a little thicker and chunkier looking. So we’re just going to mirror this and we’re going to select this plane. We’re going to join them together because we want one piece and there we go, it has a nice edge and looks great.

Let’s bring back our wake bait now. We’re going to rename this body line to lip to make things simple and to keep an eye on. We were lucky that our lip ended up pretty much in the right spot, it’s not the right angle but it’s pretty much in the right location. So now we just want to move this into the space. We click move, we want bodies, and select lip. If I needed to move it back and forth, you want to make sure you’re on the side view here and make sure you’re only selecting the arrows. If I know I only want to move it back, I don’t want to move it vertically, I just select this and move it back. If I only want to move it up and down rather than side to side, I click that. If I want to move it wherever, I can click that. I already have a section analysis so I’m going to turn that on here and we can see inside. If you don’t have one already, you can make one and the other thing you can do is turn on the opacity of your body or lower it I should say. When you do that, you can se through it. We’re going to do that quickly so we’re going to right click on the wake body opacity control and make it 50%. Now we can see through it and see what’s going on. Then we’ll go back to our move command and select our lip.

bait in fusion 360

You really want to see inside just to make sure you’re not running into any features, like I want to make sure I stay out of the cavity there. I also want to make sure I’m not impacting these eyes, but one thing you know we talked about is we were modeling the lip as it’s outside the body and we’re clearing inside the body now. So what we want to do is move this down until we are outside of the body and that’s how we make sure that our links that we chose at the beginning are the full length of our lip. If you look at any lip diagrams that have the measurements on them, they have a measurement that generally is outside of the lower body rather than the total length of the entire part. I’m going to move this down all the way and I want to make it go and then here is where I want to change my degree on the wake bait. It’s a pretty stiff angle, you can just grab this and you can fiddle it around to wherever you want to go. I think I have a parameter lip angle if you look here. I’m having a slight problem with the degrees in parameters because I never know what’s going on but I finally got my angle.

Now is probably the easiest to move it into place where you want it on the body and I just try to make sure that when I position it, I have one piece of the lip body close to the lower body but not necessarily all the way in there. Get close, but don’t shove it all the way up there. We’re primarily concerned about the angle and where it is in relation to the lower body. When you’re happy with the angle, click okay. Now what we want to do is build the part that’s going to actually stick into the lure. For that, we’re going to select this face here and click the extrude command. It’s probably easiest to look at the right view here, drag it up and into the body and now you can see we’re on join now which is why this thing went solid again. What we actually want to do is do a new body and that’s turn the lower body clear again. So we’re not joining it and we’re going to go ahead and pull it up all the way through this pilot hole. Again, like I said before, you probably want to do the pilot hole after you do this step. Just make sure you’re not into any other parts.

We’re going to actually cut out this section in a minute so we want to make sure we’re not cutting anything on the lower body, which we printed separately, that would cause us problems during the print. I’m sure there’s some sort of magic number to make sure you get it in there a certain amount, but I always eyeball it and it works for me. Now you can see we have this extra body hanging out over here and I’m going to turn off my wake. I want to join these two together so click on lip, click combine, click on tool bodies and on body 10 which then we can click join. What this will do is combine all these back to just one lip and now we can turn back on our wake body. Now we want to do this combine command again and our target body is the wake body and tool body is the lip. We want to cut, and most importantly, we want to keep tools because we’re going to need to print this lip later. We want it to hang around so click okay.

Compensating for Fit with Extra Space

Now you can see if we hide our lip, we now have the cutout in there. Let’s turn the opacity back on to 100 and now we have this nice cut out and you can imagine when you go to print this thing and you print the lip, it’s going to slide right in there. I’m printing the lip in Siraya Tech Blue which is a very hard, clear resin and I’m printing the body in, most likely, Siraya Tech fast which is a cool green resin. I know that the resin I’m printing the body in is going to shrink more than that resin I’m printing the lips in so I need to compensate for that. I want to show you these two lips and this lure to highlight an issue that you might run into. I haven’t really tested to see which resin is the best for lures, I’m just using some stuff I had and just think it looks cool because it’s green. Then I printed this lip in the same resin, obviously, then this lip is printed in Siraya Tech Clear Blue V2 which is supposedly one of, if not, the strongest resins out on the market today. The resins do have different shrink factors or ratios so if you’re going to mix resins, or change resonance between your lower body and your lip, you want to make sure that if it’s going to shrink or not you need to compensate the lower body or the lip accordingly.

creating space for lip on lure in fusion 360

This one will slide in pretty easily, this one is a little bit too big and you can see there it’s not quite fitting in and I need to sand this off here. Now it does have a little bit of elephant’s foot as well, but this shrinks a little less than 2% and this resin shrinks about a little less than 4%. Even though I fitted them in perfectly in the model when I cut them out, I needed to either offset the face here a little bit to make more room here or change the dimensions here. I find it easier to change the dimensions in the lure. What I do is I just come in to this face right here and click there and use the offset face command and just move it back about .3 or .2, you can experiment with that number. Having it a little loose is okay because we’ll fit it in with some resin or some super glue later, no problem.

The easiest way I’ve found to do that is to come in here, click this flat face, modify, offset face, and just pull it back slightly to probably around a negative .1 and that’s going to give us just a little bit of room there. Now when you have something that’s shaped like this, that can cause you a problem as well, so I want to undo that one and offset this face because what you have here is this little section in the middle and you need to open it up to make room for that flat piece on top. Let’s get back and add our lips back in here and make our changes to our lip.

Screw Holes, Fillets and Chamfers

Now remember, we talked about this kind of screw up I made before and the easiest way to solve that is to turn off the lip and in here there’s this circle which is basically the back of the hole. I’m going to turn back on the lip and make sure this thing comes all the way through and make sure we’re also on a cut. We need to make sure our lip is selected so we don’t cut the body because it already has that hole there. We want to make sure we add that hole to the lip so click ok. So now if I have my wake body, we have a nice pilot hole through there and now we just want to clean up the lip to make things easier. For this hole, let’s add a fillet on there, about a .5. I don’t think I can fill this but let’s try. I’m going to basically print this surface flat to the build plate to make things super easy so we want to add either a fillet or a chamfer. I think I can chamfer these side edges pretty easily so let’s select those.

So I could have slugged the whole thing but I wasn’t sure if that chamfer was going to work with that peak in there. Now our lip is ready to print and be part of the lure now. Again, if you wanted to, you could combine these bodies together and print it all in one piece. I will say it gets a little tricky to print that way with all the support structures so even if you’re using the resin, I would strongly recommend printing this separately and then gluing it into place later. It’s fairly easy to get lined up because we have a nice slot in here and we have our set screw coming into play that is going to force it into the right spot. That’s the easiest way to go about it. If you combine the two and try to print them with all the supports, it’s not so easy.

Adjusting the Design with Parameters

So now that I’m done here, I notice that this lift looks absurdly long. Since we’re using parameters and all of our sketches and everything we’re fully defined and that’s really easy to fix right now. We’re going to change parameters and look at our lip height. I’m going to fix that now because that’s super annoying and instead of it being our max width by 10%, I think I want that to be a lot smaller. So let’s so this at .7 which is 70%. If I click, my computer will think a for a little while and then it’ll update that to 21 and you can see the corresponding change out here. You can play with that if you know what that dimension should be. You don’t have to calculate, I just thought we would use that as a ratio. If I know I wanted it to be 25, I can just come in here and say it’s 25 and be done with it and all the calculations will update.

adjusting parameters on lure in fusion 360

I usually don't try to soften these front edges because the sharper that front edge is, the more action you're going to get. This is because it's pushing the water completely sideways around your lip. If you wanted to, you could come in and soften it up, but personally I like it with this sharper edge. Again, please keep in mind you can make this whatever angle you want, but remember to set the angle of the lure before you do the extrude into the body.  That way, you have the right angle and everything. So let's print this bad boy and see what it looks like.

Printing the Model

All right, we got the lips off the printer, then we secured them, cleaned them and all that good stuff. Now we're ready to put them in our lures and I'm going to show you a couple of different lips here and give you a couple of ideas on how to approach printing. So I have two really different lips that I'm working on for this wake bait here. The thing that I want to point out is that both sets basically start from the same profile at the top here. You can print multiple versions as long as this top profile is the same. Where it goes into the lure, I can put this lip in here and this lip is pretty ridiculous (I think I might have messed up) but I'm going to see how it swims. Then this lip here is totally different, it fits in well. What I like to do in the design phase is make sure that I have this top square section the same and I can change the bottom all I want. Then when I bring it in there to my lure, when I extrude the top up it all all fits and it's all the same. I haven't really found one I like in particular yet, profile wise, but  I think this is pretty good since it has a nice little ridge here that I added and it does help seat it into the lure body itself.


So let's get moving here on assembly. I'm not going to use this one, I'm going to use this big ridiculous one. You already have a a bait here with that lip on it over here so assembly is pretty straightforward if you don't have one of your screw eyes going through the lip like I do. It's pretty easy, you just come in here with some super glue and apply a little here. I try not to get too much in there, too much tends to leak out the sides. If you don't have this screw eye going through the lip like I do, just a little super glue will work to slide it in there and get it seated. If you do have a screw eye, I put a little super glue on this screw eye and you're going to want to screw it in.

One thing I didn't show you is I do dry fit this stuff before I go to glue because if you didn't get this lined up correctly for some reason, you won't be able to force it through the resin. It's already pretty secure because it's got this pin through it but you just have to let that dry then you're good to go. So I got a rag with a little ice purple alcohol in it which I use to clean up any rogue super glue before it dries, just so it doesn't get in the way later. There it is, the ridiculous wake bait. Let's see how it performs.


All right guys, I hope you found that super helpful, You know you don't have to use resin crankbait lips for resin lures, you can obviously print them out and put them in any lure body you want. Whether you're carving them with wood or other resins, don't be shy. The cool thing about this is you can print a ton of them for a relatively low cost as well as relatively quickly. So next up we're going to be walking through how to finish these lures hanging over my shoulder right here and the steps involved and getting that done. That video will be linked right HERE.



Take care- Tight lines