What do you want it to look like in the end?
Can you send the model before you tried the conversion?
the problem is that it does not join the surfaces/SubD faces. you can do that manually, just use the command join, but it really should give you an option…
at least i also end up with such results all the time, no matter how i set it. very confusing 
the first pic is the goal
the second is my process
I did it manually still didn’t convert to subd can you check the file?
why does it not join by itself when using the command? when i have a polysurface for instance i always end up with the result shown above. maybe i am doing something wrong?
i dont know honestly esp this is not my first time… I’ll try again tmr morning and update you guys… thank you sm!
There is a whole topology to a mesh including Joined/Unjoined, Welded/Unwelded. All those conditions give you control on how the final SubD is converted. We do not have ToSub make mesh topology changes, only react to the existing topology.
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