Without the file it’s hard to tell the exact issue. Meshes can be really problematic to begin with, it often happens that they aren’t closed, one sided, and so on. During import, we try to repair them as much as possible, but sometime it’s just isn’t. So it might not be the file size, but the data in it.
The capabilities of the devices also play an important part. A stronger device, with more memory might be able to open the file.
Hello @DragonDon, we have received the file! I have to say it is a nicely detailed model that took a few seconds to open on an M1 mbp with 16 GB of RAM. It can happen that the device you are using (an iPad based on the screen record you’ve sent us) lacks the necessary performance to deal with large files. Please note that the iPad is a pretty well-optimized device, but it may not compete with a CAD workstation in regards to performance.
On the other hand, Shapr3D is a CAD software. We can import mesh files, but they - especially STL files - tend to have several issues from intersecting or flipped polygons to tiny gaps that as Laci said we try to repair which takes time and needs performance.
Let me share an article with you about the available toolset for mesh models, I hope it helps. Please always make sure to have closed, solid meshes instead of open mesh surfaces.