Window mullion finish on molded clear windows

[thomasjmdavis]

As to muntins vs mullions, since we are being pedantic, I looked it up in the third edition (1944 with corrections through 1964) of the Oxford Universal Dictionary. I figured that would be old enough to have the definitions as they 'used to be.'

Mullion: A vertical bar dividing the lights in a window, esp. in Gothic architecture; also, a similar bar in screen work.

Muntin: A central vertical piece between two panels, the outside pieces being called stiles.

That definition of muntin is the one I know from my old books on cabinetmaking and millwork- it is the center vertical piece in a paneled door (and yes, the outer framing pieces are styles, the top and bottom horizontal pieces are rails.
Now, as to what the horizontal piece between window panes is called, I forget.

[Cajonpassfan]

Black Sharpie and a steady hand😎
Too bad mine isn't 😬
Otto

[NtheBasement]

Here's the thing... when I look at windows, unless there are curtains the glass looks black and those m things are white.

[Lemosteam]

Here's the thing... when I look at windows, unless there are curtains the glass looks black and those m things are white.

Yep, this is why I will be using a black sticky back mylar sheet behind the "glass".  Usually, I put it on the front for a glossy look, but the molded frames would prevent that this time.

Most steel framed industrial single multi-paned windows were painted, but I will be using black in this case.