Making a Gadroon Style Frame

I'll describe the processes I used to make this frame.

The basewood is cut from a length of pine stretcher split in half. The profile was then sized with rabbit skin glue and sprayed over with gesso.

Once dry, the gesso is smoothed with two grits of sandpaper, 180 then320.
To make the moulding decoration, I squished some warm compo into prepared moulds. After allowing the compo to cool, it is cut from the casting and glued to the frame moulding.

Both inner and outer castings are shown here on the frame.

On this style of frame, I prefer to glue the castings on the frame lenghts first. Then the frame is joined and the mitres filled with hot gesso. After drying, the corners are re-polished and the frame readied for painting with clay bole.

Some people like to apply many coats of bole. I prefer to just paint on two thin coats, as this can show a more interesting effect when seen through worn gilding. So, the frame is given two coats of thin yellow ochre colour and a light top of red on the high points of the compo decoration.

When dry, the bole is lightly sanded with very fine grits and polished with a short hog hair stencil brush.
This frame is to be oil-gilded, as correct for it's period, so the entire surface is sealed with a thinned coat of clear shellac.
When this shellac is well dried, I painted on a 12hour goldsize. It's as important to remove as much surplus size from the surface as possible so that when" tack-ready" for gilding, the oil size has achieved a perfectly flat finish. Together with the slow drying properties of 12hor size, the gilding will show at it's brightest.