Split polygon and split edge ring tools not working sometimes

[jamesbeswick.nz]

Hi I'm having consistent problems with using the split polygon tool and split selected edge ring tool. Like in my first image below when I try to use the split selected edge ring tool it's only done it on one face and not the others but has worked fine on the faces on the other side as you can see.

In the 2nd image when I try to use the split polygon tool on the face to the left of the first one when I right click no edge is created.

I'm not sure what the purple lines mean, to rectify I've tried:

Deleting any stray vertices on the object

Merge any unmerged vertices on top of each other
Deleted history of object

All normals are facing the same way but went to mesh display / conform as well as set to face

Used the cleanup tool

But still having issues, any ideas am I missing something obvious here?

[mspeer]

Hi!

Please clean up your mesh / topology.

Delete this edge:

[jamesbeswick.nz]

Deleted it, but still when I try to use edge ring tool it doesn't do my last 2 faces, checked and there's no stray vertices anywhere.

[damaggio]

The mesh is not clean yet James.

[mspeer]

Hi!

@damaggio  is right, if it does not work, then there is still a problem.

Please upload the scene-file for further help.

[jamesbeswick.nz]

OK so I've pasted download link below of the scene file, I've just exported the problematic piece of geometry so is small. I'm buggered if I can see where the problem is, it's only causing problems for me on the one side that's facing towards the camera when you open the file.

https://drive.google.com/open?id=12S7Ni6rOywdoii92eQZh0q4S4gMsdY2Q

[mspeer · Accepted solution]

Hi!

There is an edge error.

You see the borders, the faces are not connected here.

Just delete the face and re-create it by using Append to Polygon Tool.

(A simple "Reorder Vertices" also seems to fix it).

[jamesbeswick.nz]

Legend! Thanks for that, mystery solved by displaying borders I can see the problematic face, the tool created an edge loop right round this time. Problem must have occurred when converting a nurbs surface to a polygon one, cheers .