T-Splines and Other Stuff in Fusion 360

hi this is how to do things with t-splines and other stuff using fusion 360 this tutorial is more about modeling theory than showing how to use specific things or use specific tools I'd consider this a basic advanced tutorial it's somewhat of an experiment and I hope it's helpful I've added some links in the description below to some other videos I think might be helpful ready go so what makes fusion different from all the other parametric models out there is that there are three main modeling methods instead of just a standard solid at surface modeling t spline modeling means that we can make complex geometry much faster but it does have some distinct challenges and we'll try and cover those here essentially t spline modeling brings the poly modeling approach into a parametric modeling environment but it doesn't quite behave as consistently as regular poly modeling so we'll try and cover some of these limitations and see what we can do about it the biggest step you can make into getting the most out of Fusion it's not treat each modeling approach as completely separate from each other but instead use the advantage of each method to get the result you're looking for if you look at all of these methods the surface or patch can be knitted together to become a solid and a T spline or sculpt body can become a patch which can become a solid or if the geometry is closed it can become a solid itself well dive into this a bit more later but let's cover some theory around T splines first this is a t spline body you can move the edges around and do stuff with it but what we want to do here is make sure that we do this with purpose I don't want this to become some video riddled terminology so I'm just going to give you two more for now I'm not even sure if these are the right terms but this is how I learned this is a loop and this is a ring I'm sure you can find tons of poly modeling videos out there that go into like mind-numbing detail for how these things affect the model but there's only one that's stuck in my mind and that's simply ring around the detail for example if we want to round the size of this plane we need to make the outer perimeter into one continuous ring after we get rid of a couple unnecessary edges we have what we're looking for so let's look at what happens when we have two rings for defining our shape the trick here becomes how to transition between the two shapes you should try to keep all the detail levels roughly the same so that the transitions become easier for this one there are some parts that can just be welded together and some parts need some additional filling geometry which we try and keep as clean as we can a good rule to follow here is to try and make all the faces four-sided and define clean rings and loops when we can the same thing goes with more complex geometry like this try to match densities weld where it makes sense to weld and fill up the missing area with four-sided faces and just as a quick note before we continue and working with creased edges it automatically forces those edges to behave like a ring this is a pretty general statement but whatever type of geometry you're working with whether it's a 2d spline T spline or loft profiles less is usually better less control points less edges less whatever will tend to get you a cleaner result use as many points as you need to get the detail you want but see if there's a way to pare it down for splines for example these two are virtually identical but when we look at the curvature the one with less control points has a much cleaner geometry if we consider creating surfaces or something from this and how everything is built on top of it the one with more control points would be more likely to cause problems as we continue to build the model the same thing goes with T splines use just enough density to get the detail you need and try not to add extra where it isn't necessary if we look at a basic model like the handle on a garden hose nozzle we can start to see some of these ideas in practice there are a few rings that define the edge details and the most challenging part is to figure out how to transition between them in a clean way if we try and match up the edges on the three rings we end up with something like this it's possible there is a cleaner solution to this but for rendering purposes is fine as it is so now we'll start looking into some common problems with T splines the biggest problem is trying to maintain clean curvature certain geometry types just don't play well on fusion this is a very basic example of a curvature problem there are just too many edges mediate at one point not only that the surrounding faces are all three-sided basically fusion doesn't like it win one there's a face that has anything other than four sides and two there's an intersection where a loop goes off in a different direction essentially anything other than a plus but sometimes these problems are unavoidable when you're trying to model something complex this is the most basic example sometimes there are just no other options to making this type of geometry but because we have loops that don't result in a plus we get a pinch in the curvature why surfaces doing this with standard surface modeling can be a real pain but this is quite easy with T splines however we do see the same curvature problem in the center so just keep that in mind while we're talking about curvature this is where things start to get interesting when we're working with T splines we don't need to feel constrained or trapped in the sculpt environment for example we can create a couple bodies using T splines and manage the transition between them using patch surfacing and still maintain continuity just note that if you go back in the timeline to edit the base geometry you may have to redefine the lofted transition when you're finished T splines gives us yet another way to do this by using the match function it's less precise and it won't update parametrically but it could be helpful when the transition is much more complicated just be sure to modify your stitching tolerance if you're having trouble knitting these surfaces together transitions between surfaces are the key to a good model anyone can create the base surfaces by watching a tutorial on YouTube but figuring out the transitions is where you spend most of your time on difficult models let's continue to dive in to combining modeling methods this is an approach that I use quite often for complex models it's the idea of over building surfaces that are then trimmed back to give the result you want this is slower and more challenging than directly modeling with T splines but it has the potential to produce a much cleaner result as an example here's a model of a bumper well half of one anyway modeled three different ways this first one is only T splines it follows most of what I talked about earlier and then there are some parts of this that may look a bit odd that's just me trying to figure out a way to save it you when I turn the smoothing back on we see a model that simply doesn't come together the way we want and since for standard poly modeling the result would have been much more forgiving so let's look at another way this takes a hybrid approach where the base form is sculpted then we create extra bodies to trim out the internal details without spending time on refinement we see a couple little pinches in the geometry but this gets us most of the way there fairly quickly the third way is strictly an over build approach the benefit of directly modeling with T splines is that we have full control over the edges of the geometry this overbilled approach doesn't give us that ability so making sure the surfaces intersect where you want them to will be the biggest challenge here for this one I built a quick spline cage which you can make by using the move command on the vertices of a spline the spline cage will help us position the surfaces and fine-tune the intersections after we create our overbuilt surfaces we can use trim in the patch commands and Stitch the resulting surfaces together 3d sketches are sometimes helpful for complex models you saw earlier a quick spline cage that is just made by moving around the point of the spline using the Move command this is rather than just moving the spine points around normally one thing do you pay attention to here is the spline handles if you don't modify the handles of the spline and 2d when you go to make it 3d the handles will become locked in many cases this won't matter but if we need more control of this spline edit the spline handles first before moving it around in 3d this will allow us to do the spline handles around as well modeling the car well sort of these are just thrown together really quick to show how both methods might come together for a more complex model the first would be for a hybrid T spline and surface modeling approach and the second would be for an over build approach the first one is easier to manage and get the shape you want at the second will result in cleaner surface geometry the next step for each of these models would be to make the necessary trims to define the base geometry then begin defining details details in this case could mean finding a more precise way to transition to surfaces so this may mean trimming out a certain section of the geometry then creating the lofted section to get the transition you are looking for so now let's look at a more practical example of how t splines and parametric modeling might come together before we looked at modeling part of a garden hose nozzle and now we'll look at another part the base of this model is made with t splines but say we wanted to add some grip details the easiest way to do this would be to use the base T spline as the outer surface make a copy then define the inner surface we could do this with T splines as well but it'll be easiest if we just make a simple patch surface instead we can take the copy of the model trim out the section where we want the group to be define a curve for the profile then use that profile to create a patch surface I'm using the patch tool here instead of a loft because fusion doesn't have the ability yet to constrain the continuity on guide rails patch allows me to maintain curvature on all the edges now this inner body will be our main part and we'll chop up the outer body to become a rock grip now we just combine it all together and we end up with something that went from T splines to surfaces to a final solid part alright that's it good luck I'm out

Channel: name notimportant

Views: 230,246

Keywords: fusion 360, t-splines, surface modeling, modeling, 3d, tutorial, surfacing, patch, sculpt, solid, advanced

Id: Gf1lNAGEalQ

Length: 10min 31sec (631 seconds)

Published: Sun Jun 12 2016