Painting the fake window grilles

Procure a roll of clear (transparent) self-sticking vinyl that has a peel-off backing (this material is typically used for lining drawers and shelving).

Cut the vinyl into strips of equal width and manageable lengths. Remember that only one side will get painted, and that this side is not the side you will be peeling off and throwing away. Be sure to paint the clear vinyl and not the backing.

Decide on the exterior colour.

Using a straightedge guide, airbrush a highlight on one edge of all strips. This will be a bit lighter than the main exterior colour, and can be mixed by adding a bit of white.

Paint the other edge slightly darker to simulate shadow. Mix this by adding a bit of black to the exterior colour.

Now completely paint over the above work using the exterior main colour.

Paint the interior colour background over this.

Paint the interior highlight edge.
Make certain that this edge corresponds with the outside highlight.
We want the inside and outside highlights to be on the same edge. Peel away a bit of the backing paper to see which is which.

Paint the shadow on the other edge.

Optionally apply a complete clear coat to even out the sheen.

Easiest way for redundant painting of a narrow edge is to stack the strips in a bunch as shown to the right and also as shown on this page.

Sideview of your efforts, showing the various painting steps. The vinyl strip itself is not indicated here, but lies on the left (use your imagination and fill in the blank spot).

The exterior colours (#1-2) will show out, and the painted right side (#3-4) will display on the interior side.

For the horizontals, the highlights naturally go on top, but the verticals can go left or right depending on the ambient lighting.

Peel and stick away. Try not to stretch the tape.

Using a straightedge as a guide, cut through the doubled layer as in wallpapering, corner to corner. Don't use such a heavy hand that you score the glass. Go by feel.

Weed out the top triangular bits.

Dig out and weed the underlying bits.

Smooth down and tuck into shape.

A wallpaper roller can be useful if you have one. If you don't have one, ask your neighbour.

For simple interior faux grilles, cut and paint strips from a roll of prepasted wallpaper. Use the above method for cutting the overlaps to simulate mitre joints.

In this example, one edge was sprayed in a gradient, which gives the rounded look of bamboo to this faux ceiling grillwork.