I'm not aware of any native methods to Access to view / embed .stl files in access.

Take a look at the Images video and consider the Access Imaging Seminar

In general you don't want to embed it into your database.  Whether it is an image, document, .stl file, etc.
It really bloats your db fast and your best option is to link them in the db.

In addition to the videos above take a look at this page:  Access Open Other Programs

You can use VBA from within Access to open any external app, like your 3D viewer.  Sample code is below.  Put a command button on your form.  When it's clicked, run this code:

    Dim r As Variant, doublequotes As String
    Dim PathOfApp As String, PathOfFile As String
    doublequotes = """"
    PathOfApp = "C:\Program Files\MyApp\MyApp.exe"
    PathOfFile = "G:\My Documents\MyFile.stl"
    r = Shell(doublequotes & PathOfApp & doublequotes & " " & doublequotes & PathOfFile & doublequotes, vbNormalFocus)

Thank You for the insight.

Currently I save .png to a server and show them by linked object in my forms.

So, I think having a button open the native viewer for .STL files will work great.

Maybe in the future I'll figure out some other way.

Thank You so much!

Chris

Does MS 3D Viewer open them?
Sure there's a default Windows app that does.

If so there might be a COM plugin you could use.

running into a problem with the 3dviewer opening the path to the file on opening.
3Dviewer open fine , but loads a default example file rather than the path set in the code.

I'm including the code as written


    Dim r As Variant, doublequotes As String
    Dim PathOfApp As String
    Dim PathOfFile As String
    Dim SavedPath As String
    SavedPath = Forms!tblJobPartDetails!tblJobPartDetailsSubform.Form![3DLink]
    doublequotes = """"
    PathOfApp = "C:\Program Files\WindowsApps\Microsoft.Microsoft3DViewer_7.2107.7012.0_x64__8wekyb3d8bbwe\3dViewer.exe"
    PathOfFile = SavedPath
    MsgBox (PathOfFile)
    r = Shell(doublequotes & PathOfApp & doublequotes & " " & doublequotes & PathOfFile & doublequotes, vbNormalFocus)

@Alex   Yes windows 3D Viewer opens them nicely

Christopher
Trying to think outside of the box a bit here.

If you just double click a .stl file from file explorer does it open up in 3D Viewer (or another program)?

In other words, is it an associated file in Windows?

Windows --> Settings -->  Default Files.
Scroll down until you find Default by File Type.

Scroll down until you find .stl  - If there is a program associated it will show to the right.  If not choose the program you use to view / edit the .stl.

Once the file is associated with a program you can use the FollowHyperlink command to open the file.

See the Document Index video.
Also covered in Access Developer 39