Creating a solid link between an uneven surface perpendicular to a flat surface

[Anonymous]

I have a mesh body with in uneven surface, 1mm thick. A dental retainer. Complex mesh created from scanned impression.

I have a mesh body with a even surface, 1mm thick. A housing for a device. Simple mesh created in TinkerCad.

I want to attach the device to the dental retainer and 3D print it.

I need to create a solid link between the back teeth of the retainer and a face of the device. See attached image.

I need to create a face on the device and pull it out until it meets the retainer. But how do I get it to get it to combine with just the uneven surface of the retainer and not puncture the retainer whose thickness needs to remain 1mm all over?

Any ideas?

[laughingcreek]

Here is a screen cast of one possible work flow.  I can think of a few others.  If your printing software will except the model after it is combined, I wouldn't bother with the last make solid command.  

[Anonymous · Accepted solution]

Here's another way without MakeSolid's remeshing.

The basic idea is to separate the region of the exterior surface temporarily > run a BooleanUnion of that region and the device object > combine this result with the rest again and to run CloseCracks finally.

At the moment I define the region to separate I use a special selection option: When you are in SELECT and double click on another, intersecting object B > MM selects all faces inside object B. This selections is grown several times doing Modify/ExpandRing ( Shift+: )

[Anonymous]

Thank you. This is exactly what I wanted. I'm new to Meshmixer so there is quite a bit from me to understand here.

[laughingcreek]

I completely forgot about the original function of mesh mixer, which was to mesh mix.   It's a pretty fun tool to use.  If your going to be doing this much you might want to create your own part, and just bloop it on.  Might save some time.

[Anonymous]

Hi,

This looks like a really good solution for me.

I have tried it with a part I created in TinderCAD.

However, it won't let me add it as an "Open Part"... it give the following error...

Make Part failed to initialize. Most likely your selection does not have any suitable boundary loops.

I have tried Solid Part but the connect is not what I want.

Have you any ideas how to prepare the component so it can be added as an "Open Part"?

I've attached an stl of the part and an image of the error.

Many thanks,

[Anonymous]

stl not uploaded... zipping it to see if that makes a difference

[Anonymous]

Hi,

Thank you very much for this solution. In the video it is exactly what I want. However, I'm unable to follow the steps because you are using a MAC and possibly key commands which I can't follow (I'm very new to MeshMixer). Would it be possible to redo it using the menus?

[Anonymous]

Basically the only macOS specific key used in the screencast is Opt(ion along with that "stair" symbol). This is the Alt key on Windows.

For some reason I prefer to navigate in MM via modifier keys (this works in both MM navigation modes > Preferences):

Alt+LMB-drag = Rotate

Alt + Shift + LMB-drag = Pan

Alt + Ctrl + LMB-drag = Zoom

Doing this you train your left hand to stick to the keyboard and allows to use the keyboard shortcuts too.

Here I used:

T = Transform (whether EDIT/Transform or SELECT/Deform/Transform depends on whether there's a selection or not)

S = Start a new selection

G = Expand a selection to a face group

Shift+. (fullstop) = Expand a selection by one ring of faces (Watching the screencast without shortcuts below you might understand that this is much quicker)

ESC = Cancel tool or leave SELECT

Y = Separate selection as an isolated object (For some strange reason Screencast records a Z instead - I'm on a German keyboard layout)

-----

Anyhow here's the screencast without shortcuts (using Fusion360 navigation mode). Only exception is Shift. This needs to be pressed to activate a second object for Booleans.

Using your device object: This is made of as few triangles as possible. BooleanUnion handles that but needs eternities to refine the device. Instead Remeshing the object before is much quicker. to get a good density I use LinearSubdivision three times at its max Density.

Screencast will be displayed here after you click Post.

4beda03d-e7b4-4d7b-ba0f-6ab2c62586bd

[Anonymous]

Again