Lyx : After Changing numbering, Part appears in regular text in pdf

Lyx. Document class : article (paper)

I wanted numbering for the TOC but without the "Part I" before it.

So I went to Document -> Settings -> Numbering & TOC and changed the numbering column to "no" for all (Part , Section etc.) .

Now when I define some text as Part it doesn't show up next to Part I as desired. The problem is that in the PDF the text appears as regular text not big bolded text as normal.

What is strange is that if I define some text as section it does appear in its usual big bolded text.

Any ideas?

-
I assume you're using LyX? –  cgnieder Nov 30 '12 at 13:14
Yes. Thank you. I'll add it to my question –  oopsi Nov 30 '12 at 13:15
Do you have to use that document class? There is no such problem with, for example, the normal article class. –  Torbjørn T. Dec 2 '12 at 19:02
I don't have to.. But i prefer to use it. –  oopsi Dec 2 '12 at 19:58

As Torbjørn mention, one solution is to use another class, as article or extarticle.
With paper class, you can define the part title as Part* (instead of Part)followed with a ERT box (Ctrl+L)with \addcontentsline{toc}{part}{Part title}
\part*{Part title}