Float frames and floater frames

Two different things share almost the same name, and confusing them wastes money. A float frame shows the edges of a piece of paper. A floater frame surrounds a canvas with a gap. Neither can do the other's job.

Float mounting: showing the artwork's own edge

A conventional mat covers the outer quarter inch of the artwork on every side. Usually that is fine. Sometimes what it covers is the point.

Deckle edges on handmade or mould-made paper — the soft, feathered edge produced by the papermaking process — are a mark of quality and were never meant to be hidden.

Plate marks on etchings and engravings are the impression the printing plate leaves in the damp paper. Collectors look for them; a mat hides them.

Printed borders and signatures in the margin of a print, which are frequently part of the work.

Torn or irregular edges on contemporary work, where the edge is a deliberate gesture.

For all of these, a float mount lifts the artwork slightly proud of a backing board so its full outline is visible with a shadow around it. The effect is that the sheet appears to hover.

How to float mount

1. Choose the backing. A rigid, acid-free board — 8-ply mat board, or an archival foam board. It should be cut a little smaller than the frame's rabbet so it sits comfortably inside.
2. Raise the artwork slightly. Small pads of foam board or mat board offcuts, glued to the back of the artwork's mount and hidden beneath it, lift the sheet perhaps an eighth of an inch. This is what creates the shadow.
3. Hinge the artwork to the raised mount with archival hinges along the top edge only, so it can move with humidity.
4. Add spacers. Clear plastic strips sit in the rabbet at the frame's perimeter and hold the glazing off the artwork. Without these the glazing rests on the paper and, in humid conditions, bonds to it permanently.
5. Assemble glazing, spacers, float-mounted artwork on its backing, then the frame's retaining points.

The two things that go wrong are skipping the spacers, which is a conservation problem, and lifting the artwork too far, which turns a subtle shadow into an obvious platform. An eighth of an inch is plenty.

Floater frames: for canvas and panel

A floater frame is a completely different object. It is essentially a shallow tray: an L-shaped profile with the upright on the outside, open at the back, deeper than it is wide.

The canvas is attached from behind, screwed through the frame's base into the stretcher bars, and sits inside the frame with a deliberate gap of an eighth to a quarter inch all round. There is no glazing, no mat and no backing board.

Why canvases need this

A conventional frame has a rabbet of a quarter to three eighths of an inch. A stretched canvas is three quarters of an inch deep on standard bars and an inch and a half on gallery-depth ones. It physically will not fit.

The alternatives people try are worse. Removing the glazing and backing from a conventional frame leaves the canvas sitting proud of the frame face, which looks like exactly what it is. Sitting a canvas on top of a frame and screwing through the front is visible from every angle.

The floater is the purpose-built solution, and it is what galleries use.

Choosing one

Size by the canvas, not by an opening. Floater frames are sold as "16x20 floater for a 16x20 canvas". The internal dimension is slightly larger than nominal to create the gap.

Match or exceed the depth. The frame must be at least as deep as the stretcher bars. Slightly deeper is good — the canvas sits marginally recessed, which reads as intentional. Shallower means the canvas stands proud, which does not.

Gap width. An eighth to a quarter of an inch. Narrower looks like a manufacturing error; wider makes the canvas look adrift.

Finish inside the gap. The inner face of the frame is visible through the gap and is part of the design. Black is the usual choice because it reads as shadow. Natural wood and gold are both used deliberately, and a mismatched or unfinished inner face is an immediate tell of a cheap frame.

Fitting a canvas

Lay the frame face down, place the canvas into it face down, and centre it by eye against the gap on all four sides — measure it rather than trusting the eye, since the gap is small enough that a sixteenth of an inch of error is visible.

Then screw through the frame's base into the stretcher bars, usually two screws per side, using screws short enough not to come through the front of the bar. Some floater frames come with mounting brackets instead, which is easier and equally secure.

Which to use

The dividing line is simple: if it is paper and needs glazing, you want a float mount. If it is a rigid object that hangs unglazed, you want a floater frame.

Cost

Float mounting a print costs slightly more than matting one, because spacers and an archival backing are needed and the mounting is more fiddly. It is not a large difference.

Floater frames tend to cost a little more than conventional frames of the same nominal size, since the profile uses more material. But they need no glazing, no mat and no backing board — three things that add up quickly at larger sizes — so a floater-framed canvas is frequently cheaper overall than a conventionally framed print of the same dimensions.