- [Kevin] By the end of this tutorial, you'll know how to use
Fusion 360 to turn an STL or OBJ mesh file into a solid body. I'll also be showing you
several different tricks to help clean up your
files after the conversion. I do have another tutorial
where I covered similar steps, however, not only will this
tutorial be updated to reflect the most recent UI changes, but I'll also be sharing
a few extra tricks. (logo chiming) You likely found this
tutorial searching for steps to convert your STL files to a solid body. Many of you will find something
you like on Thingiverse, or a similar website, with the intention to alter
it before 3D printing. For this demo, I'm going to use two different Thingiverse files, which I'll link to on
this tutorial's resource page at ProductDesignOnline.com/15. That's ProductDesignOnline.com/15. The first Thingiverse file we'll convert is this hinged box that I've linked to on my web page along with
credit to the original author. This box is fairly simple, and I'll use it to cover
the overall process. Then, we'll use a more complicated object, to cover common problems
you may encounter, as well as some additional
tips and tricks. Once the file is downloaded, there are two ways that we can
get the file into Fusion 360. The first option would be to upload the file in the Data Panel
or the Fusion 360 hub. I'll click on the Data Panel icon in the upper left hand corner. From here, we would need to
select the blue upload button to select the STL file
from our local machine. The second method, which is
quicker and more efficient, would be to use the Insert Mesh command. If I select the insert dropdown list, you'll notice that we have
an Insert Mesh option. The Insert Mesh feature will work with both STL and OBJ files. Additionally, you can access
the Insert Mesh command from the shortcuts box,
which is opened with a the keyboard shortcut
letter S, as in Sierra. After selecting the Insert Mesh command, your computer's local
folders will open up, where you'll have to select the file from your local hard drive. I'll navigate to my downloads folder and then I'll select the box STL file. The reason I prefer
this Insert Mesh option over the upload option is the
fact that we can now define the position of the model all
within the Insert Mesh dialog. Let's take a look at all
of the available options. First, you'll see that
we can set the unit type. This is important to ensure that your model comes out the right size. You'll want to double-check
the file's dimensions before you go to 3D print the file. You may even have to check
the file's Thingiverse page to see what units the
original creator used. Second, you'll see that we have the Flip-Up Direction button. This button simply lets
us flip the up direction from the Y axis being up
to the Z axis being up. As in, we're changing the
direction of the model, not the orientation of
our file or viewcube. This can be helpful if the original author modeled the file in the other orientation. I'm now going to hit the eyeball icon next to the Origin folder, in
the Fusion 360 Browser. Looking at this mesh file,
we can now see that its center point is not aligned with the center origin point of our file. This may or may not be
important with your project. However, if you do need to fix this, then you can simply
click the center button in the Insert Mesh dialog. You'll notice the model's center point is now aligned to the center of the file. Just below the center option
is the button, Move to Ground. The model is currently centered on the origin point in all directions. I'll look at the model from
the front face of the viewcube so we can take a look at what happens. If I now click the move to ground button, you'll see that the file snaps to the ground or the XY origin plane. It's important to note that it will snap based on the lowest point of the model. This model has a nice flat base, but if you have any objects
sticking out the bottom then those will be referenced first. The last button that we have here is the Reset Transformation button. This will reset any
changes that you've made and it will place the mesh file into the original imported location. If I select this, you'll
see the model is now away from our center origin point
as I originally pointed out. Last but not least, you'll
see that you can toggle open the Numerical Inputs section, which allows you to
define exact distances. This isn't used all the time, which is why it's closed by default. However, this can come in
handy if you need to move the imported model around a pre-existing model or to a specified distance
away from the origin point if the model will be inserted
into a larger assembly file. For now, I'll click the Center and Move to Ground
buttons and I'll click OK. Now that we have our imported mesh file, we're ready to convert
it to a solid BRep body. Then, I'll show you a few different ways to clean up the file's mesh triangles. For now, we can turn off the
visibility of the origin folder by selecting the eyeball
icon in the Browser. I'll toggle open the bodies folder so we can work with the mesh body. If I right-click on the Mesh body, you'll see that the
option to convert the Mesh to BRep is currently not available. This is because we have to first turn off the design history, as mesh files are written
in a format that Fusion 360 cannot process and record the
steps in the timeline below. I'll right-click on the file name or the top-level assembly
in the Fusion 360 Browser. You'll then see at the
very bottom of the list we have an option titled, Do
Not Capture Design History. After selecting the option
you'll get a warning that all design history will be removed and further operations will not
be captured in the timeline. Watch what happens to the timeline as I click the blue Continue button. Our timeline disappears, as we're no longer recording
the history of this design. We can now right-click
on the mesh body again. This time, you'll see
the option Mesh to BRep. The Mesh to BRep dialog will then open up, where we can choose to create
a new Component or a new Body. I'll leave this set to New Body, and I'll click OK to convert the file. You'll notice this file
converted very quickly, without any latency. The time it takes to convert
your file depends on the size of the file or how many
mesh triangles it's made of. We'll take a look at a
more complex file later on, which will take much longer to convert. In the bodies folder, we
now have a solid body, along with the original mesh file that is automatically
hidden after the conversion. If you're certain that you no longer need to reference the mesh body
then you can right-click on the mesh body and
select the delete option, which will permanently
delete the mesh body. Let's now take a look at some tricks to help clean up a converted STL file. You may be wondering why your file has all these lines running across it. In short, stereo
lithography, or STL files, are made up of triangular facets. Each facet is created with three points representing the vertices of the triangle, along with a perpendicular direction. Once we convert the file to a solid body, the small triangle facets will remain on the exterior of the shape. The conversion process essentially fills the exterior boundaries,
making it a solid body. This brings me to one key problem that you may face while converting mesh files. If you ever go to convert
a file with the mesh to BRep command and end
up with a surface body, then that means you have
a hole or multiple holes somewhere around the model,
which prevents the exterior facets from being filled. In such cases, you would
have to use the surface tools to patch the holes, which I'll be showing you a
few tricks on in just a bit. The first method and simplest
way to start to clean up converted files would be
to simply select a face and then hit the Delete
key on your keyboard. I'll select one of the large triangles in the lid of the box. Watch what happens as
I hit the delete key. Fusion 360 will attempt to
self repair the face, which, if successful, results in one solid face. The key thing here is that the facets need to be on flat planes. I'll talk about curved
surfaces in just a minute. If I spend a few minutes
just deleting one face at a time and letting it self repair, you'll see I will end up with
some pretty good results. The problem with converting
STL files always begins with the curvature of designs. Even this simple box shape has curvature on all of its rounded edges. Lets first try to delete some
of the faces of a corner. I'll hold the shift key
and I'll select a few faces that make up this corner. Once selected, I'll hit the Delete key. You'll notice that the faces of curvature don't self repair very well. I'm going to hit the undo command so I can show you a neat trick. Watch what happens as I repeat these steps while under the surface tab. After selecting the surface tab I'll select a few of
the corner faces again. Then, I'll hit the Delete key. You'll notice that our faces
were deleted this time, as Fusion 360 still isn't able to self-repair this curvature. Because some of our faces are now missing, we'll end up with a surface
body instead of a solid body, as I mentioned a minute ago. At this point, we can
revert the previous step and try to alter the
solid body differently or we can proceed by
repairing the surface body. Let's look at a few tricks to
repairing the surface body, as I've found this is often
the better route to take. I want to first delete the rest of these facets that make up the corner. To select them all I'm going
to click the Select dropdown menu and I'll find the selection
priority flyout folder. I'll click the Select Face Priority option so I can only select faces. I'll also look at the
selection filters to make sure the select through option is turned off. This will ensure that we don't
accidentally select faces on the other side of our mouse click. I'm also going to use the
paint selection option, so we can paint or drag the
mouse over all of the faces, allowing us to quickly select them. In scenarios like this, I like to click on the closest
face that I'm going to keep, or in this case the
large face on the right. Then, simply drag the mouse or paint over all of the
faces to select them. Now we don't want to delete
the large face on the right, I simply used that as a
starting point to ensure that I selected everything. We'll need to hold down the
shift key to deselect that face. I can now hit the delete key to delete all of the facets that make up this curve. What we now want to do is
figure out the easiest method to recreate a rounded surface
to patch this opening. Because we're working
with a surface model, you'll want to work with
the surfacing tools, which are all nested
in the new Surface tab. If you're new to Fusion 360
then you can remember this by looking at the color of the tools. You'll notice the orange
surface tools correlate to the orange surface body in the Browser. The first trick I always
try is the patch command, which lets us patch openings of surfaces. I'll select the patch
command in the toolbar and then I'm going to select
the hole that we need to patch. Notice how it selects the
entire outline of the hole, as I have the enable
chaining option turned on. I'll click OK to take
a look at the results. First off, you'll see that
the surface is yellow. This doesn't affect the model in any way other than appearance. Surfaces in Fusion 360
have one yellow side and one gray side so
they're easier to tell apart in comparison to solid faces. To switch it around we can use the reverse normal command
in the Modify dropdown list. Generally, I'll make sure
all the faces are aligned the same way as it's easier to
look at the surface geometry. Now that we've reversed
the face we can see that we have some issues with it, as it resulted in irregular geometry. Looking at it from an angle, you'll see that the path has
this bulge and it doesn't quite follow the rounded
corner that we desire. I'll hit CMD + Z two times to undo both the reverse normal and the patch commands. If you don't get the
results you're looking for with the patch command, then I always recommend
trying the Loft command. This would be a pretty simple loft so I'll activate it from
the create dropdown list. I'll select both edges and
you'll see that creates a lofted surface from
one edge to the other. Now we want this loft to
follow this curved geometry, so we can reference it as a guide rail. This, however, is where I
see people often go wrong. They try to reference the
geometry from the mesh file, which doesn't work well
because as we looked at earlier we get these choppy edges
from the mesh triangles. The key takeaway here is that
you'll often need to recreate simple sketch geometry to reference while you patch and repair your models. I'm going to close out of
the loft command for now and I'll use the Project command with a keyboard shortcut
letter P, as in Papa. What we want to do is
project these two lines that touch the endpoints
of this corner arc, that way we can redraw the arc. With the project command active, we'll first need to select the top face. We can then select the
two lines and hit OK. We can now go to the create dropdown list, the arc flyout folder, and
select the tangent arc. The tangent arc is
perfect in this scenario as we have our two tangent endpoints. I'll select one endpoint
and then the other. We can now finish the sketch and reference this tangent arc with the Loft command. I'll reactivate the Loft command and I'll select both surface edges. This time, for the rail selection, we can reference our smooth tangent arc and I'll click the OK
button to complete the loft. If we now inspect the
corner you'll see that we've successfully fixed
it with smooth geometry. However, our model is still
currently a surface body. To get our solid body back we'll have to stitch the surface bodies together. I only repaired this one corner, so you would want to repeat
this process to all areas of the model before you go
to stitch them together. I'll select the stitch
command in the toolbar. Then, I'll select all
of the surface bodies in the Browser and I'll click OK. We now have some solid
bodies in the Browser, which we can alter with
the Solid modeling tools. In this scenario, maybe
you're looking to add custom text to the lid of the box or to create slots or
storage compartments inside. After altering your solid model, you could then click the Tools tab, select the 3D print icon, and resave your model as
an STL to 3D print it. Another option that you have
while trying to repair your converted file would be to
merge the mesh triangles. With the paint selection
tool still active, I'm going to drag over some of the facets that make up the hinge of this model. Then, within the surface tab, we'll need to go to the
modify dropdown list. You'll then see there is a merge option about halfway through the list. If I click OK you'll see that Fusion will merge all of the faces. Merging faces can be a lot quicker than recreating the faces from
scratch with the surfacing tools; however, you won't always
end up with smooth geometry. You'll see that this hinge
resulted in an irregular shape similar to the rounded corner. You'll have to play around with these techniques as a lot of it
varies from model to model. Sometimes the merge
technique works quite well, but ultimately it depends on how the triangles make up the model. A lot of organic models
will contain more facets, as more small triangles are required to define the contour. Let's now take a look at a large file that is made up of a larger number of facets. But first, let me know if
you're enjoying this tutorial by clicking that like
button, and be honest, if you're not liking it
then hit the dislike button. Making these concise and
thorough tutorials does take quite a bit of my time, so
help me out by commenting the words STL to SOLID
down below in the comments. This will help more Fusion 360
users discover this tutorial, and in return, I'll be
able to reach more people and continue to create more tutorials. The second file I have is
this pen holder that's shaped like a fish that I also
grabbed from Thingiverse. I'll insert the file with
the Insert Mesh command and I'm just going to
center it as we did before. Just looking at this file
you'll see that we have a large number of triangles
that make up this shape. As you work with more mesh
files you'll start to get an idea of what shapes
will be harder to convert. I'll turn off the design
history for this model and I'll try to convert this
STL to a BRep solid body. As you'll see, I got a warning message and the conversion was aborted
as the number of facets is too high for Fusion 360 to process. In some scenarios with a
large number of facets, but fewer than this, you may
still get a warning message, but it will give you the option to proceed anyway with the conversion. Either way, I would recommend
that we don't proceed and we attempt to lower
the number of triangles. There are two approaches that
we can take when this happens. We can either split
this model into sections and then convert each
section one at a time, or we can reduce the
number of mesh triangles. You can click that link in
the upper right hand corner to watch my other tutorial
on splitting both mesh and solid files into smaller parts. I've also put the tutorial
on the resource page. If your file is extremely large, then you can split it up into sections, and then follow the steps
I'm about to show you. Let's take a look at how to reduce the number of mesh facets. You may have noticed that I
have a Mesh tab in my toolbar. To see the mesh tab, you'll have to turn on the mesh preview. Select your username in the
upper right-hand corner. Select Preferences. Then, select the preview
tab on the left-hand side. From here, you can turn on
and apply the Mesh preview. Note, it's in preview
mode, as the functionality of the Mesh tools is
still being worked on. Under the mesh tab, we
will find a reduce feature in the toolbar, or in
the modify dropdown list. We'll first have to select the mesh. It's important to note
that you can either select certain areas of the mesh,
or you can select the entire mesh body by selecting
the body in the Browser. Then, we can change the Reduce Target to the Face Count option, as we want to lower the
overall number of facets. Above that, we have the reduce type. Adaptive means Fusion 360 will
adapt the surface triangles how it best fits the overall shape; whereas, the uniform option will force all of the triangles to be
the same shape and size. Generally, you'll want to
use the adaptive option, to ensure the object is
closest to its original shape. We then need to define the
number of facets to be used. This model has over 100,000 facets, and Fusion 360 doesn't
allow more than 50,000. Ideally, we would have no more than 10,000 and you ultimately want to aim for the lowest amount as possible, without ruining the shape. You may even find that after
you reduce the mesh triangles that you need to undo and try
a smaller or larger amount. For now, I'll type out 5,000. Lastly, we have the option
to check Preserve Boundaries. This option controls whether Fusion 360 is allowed to modify
any open boundary edges. This is particularly useful
if you split your mesh files in half and will have two
separate bodies meeting at open boundaries that
you wish to merge later on. We don't have an open
boundary with this model, so I'll leave this
unchecked and I'll click OK. If I now right-click on the mesh file to convert it to a BRep, you'll see the option is not available. You will have to be in the solid modeling tab to access the option. This is another common
problem that I see users face, as they wonder why the
option is not available, even after they've turned
off the design history. I'll select the Solid tab, then right-click on the mesh body again, where this time I'm able
to select Mesh to BRep. After clicking OK it looks like the model converted without any issues. Another important thing to note is that some very complex STL models may have so many triangles
that Fusion 360 won't be able to reduce them
without the software crashing. If you do run into this,
then I suggest reducing the mesh file in Autodesk Meshmixer, which is also available
to download for free. Most of the mesh functionality in Fusion 360 was derived from Meshmixer. So you should be able to use
Meshmixer's reduce command by following the same
steps I just described. I'll also add some helpful links to the resource page. Now that we have a solid
body we can clean up the file using the procedures I covered
earlier in this tutorial. I can simply use the delete key, or I can merge faces using
the surfacing merge tool. One important thing to note, when you're working with very
organic shapes or models, you'll often find that
there is simply not a way to completely get rid
of the mesh triangles. If you're looking to get
rid of them completely, then you're better off
recreating the shape with the t-spline sculpt tools, or in some cases, the surfacing tools. At this point, you have a solid body that you can attach to another solid body, customize with your name or
design, cut a hole out of, or alter the design for
your individual needs. If you made it to the end
of this video then let me and the community know by commenting below what type of 3D printer you have and what you like and dislike about it. Last but not least, I
want to give a shout out to this week's Patrons that joined us in the Product Design Online community. Special thanks to Kenneth
Chang and Kaizen Z for supporting all of the
Fusion 360 content that I make. As always, I truly appreciate you taking the time to watch this tutorial. Click that thumbs up icon if
you want more free content and click on that playlist in
the lower right-hand corner to watch my Learn Fusion
360 in 30 Days series. To be a part of the Product
Design Online community, be sure to subscribe and check us out on Patreon by clicking that
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