Unable to merge coplaner faces

I have 2 faces that I know are coplaner and they will not merge using the Merge 2 coplaner faces tool. I needed those to merge because I had to move the face past one of the edges of the faces as you can see. Now have a little gap and cant do booleans to it. Thanks.

Need a file.

top.3dm (1.1 MB)

Something strange is going on here and I haven’t figured it out yet.
If you isolate this single trimmed surface:

It seems to have overlapping trim curves, and an isocurve that crosses over the open center.

Huh?

It’s pretty easy to fix:

  1. Isolate the surface, detach it’s trim curves.
  2. Edit the trim curves so the overlap is eliminated,
  3. Retrim the surface

I also tightened up your tolerance to 0.0001" since the trim curve overlap was only 0.007" wide, and that’s within the order of magnitude of the tolerance.

I see the problem now. Your rectangular pockets overlap by 0.007".

Looks like you might have some overlapping, coincident surfaces too.

Yep. I think I will rebuild from scratch, not too complex a part. See a way to repair the overlap so it is one clean plane?

  1. Explode the surfaces
  2. Kick up your tolerance to 0.0001"
  3. RebuildEdges on all surfaces using default setting.
  4. Isolate and Trim surfaces as needed. I think you discover your confusing coincident surfaces in this process.
  5. Join the results