Normal Map issue - Orc Shield

Burpee

Hi guys ! 
I'm tryin' to learn the game asset workflow, with proper baking, low poly mesh etc... so I tryed to do a shield,

Here's the Hi-rez



The Low Poly



So I bake the maps in substance painter, 

Here's the NM map 




So before texturing I wanted to see if my NM is working inside of Marmoset, and here's the weird stuff 

If I export my mesh from maya with all part 

 
I have no issues in Marmoset


but if I group them ( I wanna group em to texture it easier inside of Quixel / Painter ) and export the center piece is just messed up



any idea why ?

Thanks !

Scruples

Try deleting your mesh history before combining.
Edit: oh also check the names of your UV channels, they might be getting combined improperly if one is set to useing a differrent UV channel, if that's the case you can just copy it to the default one before combining.

I just realized you're using the word group, you should probably be using Mesh>Combine, instead of grouping and then exporting selected which is what it sounds like you might be doing.

Burpee

Hey! Actually yep I'm Combining them, not grouping ^_^" and I tried to delete history, freeze transform etc...  I checked the UV channel, everything is normal, 
this is so weird ! I tryed with a normal map from painter and I got the same issue 



Still I managed to texture it inside of painter ( https://www.artstation.com/artwork/0zn1K )  ( I thought at first that substance will create a differente shading group per obj not combine ) but It's weird, even If i export only the wood part, I have that issue

 even without normal map applied some faces are going crazy , ( I tried to soften edge / set to face in maya )


Edit , ok maybe I found where  the issue came from, when I look in the UV editor it looks like my UV shell is divided in multiple UV shell


Any idea how to merge em back ?

Scruples

Inside the UV editor select all the uv's and go to Polygons>Merge UV's (click on the dialogue box option) then set the threshold very low .00001 and merge. If that doesn't work then the vertices aren't actually connected and you have to do the same thing but for the vertices.

Burpee

worked perfectly Thanks mate!

almighty_gir

just as an FYI:

the wooden part of your shield could literally be a big flat plane, and it would still have just as much detail after baking.

Burpee

@almighty_gir

Yes that's what I thought afterwards, I could also improve the polycount right ? 
Thanks!