That was scanned on the turntable, with multiple heights / angles / distances, and the part flipped 3 or 4 different ways to capture all the faces possible, and the resulting scans merged with Handy Studio.
Re: alignment to a plane in Meshlab- it’s pretty easy to do.
Start by identifying a planar feature in your part and selecting some polys or points, depending on what you’ve got:
The average of these faces will become the ZX plane in a moment.
You don’t need clean selections or to get every single face- you can see what my selection set here looks like.
(Incidentally- using the workflow detailed a few posts above, this scan comes straight into Inventor with the dimpled panel in the middle measuring 30.5" across, which is at least within the margin of error of the tape measure that I’ve previously measured at. Now, granted, the scan says that it’s curved when the actual part has a nice straight line and most everything is square or at 45 degrees, but the raw measurements are very close.)
Go through the menus as follows:
I’ve picked the ZX plane here, but you can pick whichever you like.
For the first alignment, you want to have rotation on any axis.
With the axes turned on, you can see that we’re now at least reasonably parallel to the ZX plane, though not exactly laying on it. (The face is, as mentioned, curved where it shouldn’t be.)
You can also see that we’re rotated wildly about that plane. I’ve selected some faces on a panel which is (in the real world at least, but not in this scan) square to the first one.
This time I’ve selected the YZ plane, and I’ve told it that I want to only rotate on the Y axis. This should have us square (more or less) to two origin planes.
And it does:
From here, just use the transform: translate tool to handle any remaining alignment requirements by moving in the + or - direction along any of the three axes. Make sure you turn preview on, though, so that you can see what you’re doing, and once you click the apply button ALWAYS close the tool and re-open it before you do an additional translate, because at some point you will forget to re-set something back to zero and you’ll wind up moving it a second time by accident.