Fillets
Fillets are tiny frames meant for an extra layer of decoration in custom framing. They can be made of wood (or less commonly metal). Unlike a normal frame, the lip of the moulding is reversed: not capable of holding in glass, but capable of slipping under the lip of the primary moulding. There are various ways of using a fillet in framing. A fillet can be placed under the main frame or under an inner frame (or in between the two), under or between mats, or a combination of both.
Under The Frame: Find a frame you love but wish it has an extra something? That’s where a fillet can come in handy. Pair your main frame with a similar fillet for an extension of the original profile, add a decorative element such as beading, or build contrast by pairing the original moulding with a fillet that adds something new.
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Under/Between Mats: A fillet is a good choice under a mat if you want to draw the viewer’s eye in from the frame, towards the framed artwork. It can be placed at the edge of the mat, creating a window for the artwork. Or it can be stacked between two mats, creating an element of depth as well as interest.
Combination: Use multiple fillets: to add interest to your selected frame, and then another or the same fillet in the mats to carry the eye inwards. You can also add a fillet to an inner frame (or slip).
Fillet Profiles: Traditional fillet profiles often sport a sloped profile, have some kind of ornate decoration such as beading or scrolling, and in a traditional variation of black, silver, or gold. Contemporary fillet profiles are generally more sleek, less ornate. They often have squared profiles, and a wider variety of colours.