CreatParams to remove titlebar (vb.net)

Question

I'm trying to build a custom form. I plan on building my own titlebar, so, I need to remove the standard one.

Here is the code so far.

    Protected Overrides ReadOnly Property CreateParams() As CreateParams
    Get

        Dim cp As CreateParams = MyBase.CreateParams

            cp.Style = cp.Style Or Not CInt(WindowStyles.WS_CAPTION)
            Return cp

    End Get
End Property

There is a small white frame always drawn. Can't get rid of that. This, with WS_CAPTION was a random test (that worked). So I have no idea where to go from this. I'm using VB.NET 2015, Win10.