3 Missing Beads Recarved on a Georgian Cornice with Milliput and a Riffler File

Taking the profile before any putty goes on

A Georgian bead-and-reel cornice repeats on a fixed pitch, commonly somewhere between 8mm and 12mm centre to centre, depending on the cabinetmaker. Before filler reaches the damaged section, press a strip of Blu Tack or a purpose-made contour gauge against three or four sound beads beside the loss. That record gives the bead diameter, the spacing, and the depth of the quirk between beads. A cheap plastic profile gauge from Silverline reads the section well enough for this job, although a wax squeeze from the intact run is the reference that keeps its value while the recarved area hardens.

Carve to the worn bead that is actually on the cornice. The surviving run will be a little uneven, and the crowns of the beads are often flattened by two centuries of dusting and wax build-up. Geometrically fresh beads look new as soon as raking light crosses the moulding. Put a lamp low across the sound section and photograph the highlights on the crowns; those highlights show how much flatness has to be copied in the new work.

Building the three missing beads in Milliput

A slip of matching mahogany can be let into a loss and carved in place, and some repairs call for it. On three beads standing proud on a cornice edge, the wood insert is a troublesome little block set against a curved ground with very little glue surface. The grain in such a patch also tends to run the wrong way for the crown of a bead, so a duster can chip it again.

Milliput Standard, the yellow-grey two-part epoxy putty, has no grain direction, files cleanly after cure, and will hold a sharp arris. Cut equal lengths from the two sticks and knead them together until the marbling has gone and the colour is even. At normal room temperature the working time is around one to two hours, with a full cure overnight. During the first part of that window it can be pushed and wet-formed; after about twenty minutes it is already losing the easy movement that makes shaping pleasant.

Key the ground before the mix is pressed in. Scratch the bare wood where the beads have gone with the corner of a scalpel, then wipe the area with a little methylated spirit to lift dust and old wax. The scratches give the epoxy a grip, and the spirit cleans away the material that would otherwise sit between the putty and the cornice.

Press a slight surplus of Milliput into each bead position. Form the domes roughly with a wetted fingertip before the surface begins to skin. This wet-forming stage removes perhaps half the filing that would be needed after cure, and it also helps the putty sit tight into the quirks.

Colour can be pushed in at the mixing stage on darker timbers. A pinch of dry earth pigment, raw umber or burnt umber, kneaded through the Milliput pulls the yellow-grey mix toward mahogany, so a thin spot in the later colouring does not flash pale. Alec Tiranti and other pigment suppliers sell the dry colours; use very little, because heavy pigment loading weakens the cure.

Leave the repaired run slightly overfull. A fat bead can be filed back to the profile gauge with control, while a lean bead usually means a second mix. That second application rarely bonds to the first as cleanly as the first mix bonds to the keyed ground.

Filing the cured beads with a riffler

The shaping is done with a riffler file, the double-ended type with a curved, tapered end. A No. 2 or No. 3 cut half-round riffler around 150mm to 200mm long reaches the quirks between beads better than a flat needle file. Begin only once the Milliput is fully hard; half-cured putty tears under the teeth and clogs the file.

Establish the quirks first, using the edge of the curved end to cut the small valleys between adjacent beads. Then lower the domes until they meet those valleys. Check against the wax squeeze after only a few strokes. Hard epoxy can disappear faster than expected under a sharp riffler.

Finish with worn 320 grit paper folded over the riffler or wrapped around a slip of dowel matched to the bead radius. The filed Milliput needs the same quiet sheen as the surrounding shellac once polished. File marks left on the bead crowns will catch light across the run.

Reviving and colouring the shellac

Old shellac on Georgian cornices is commonly matte, crazed, and slightly bloomed. Most of these finishes respond to a reviver before any stronger intervention is needed. Draw a rag barely damp with methylated spirit once over a test patch. If the methylated spirit pulls the finish sticky and even, the film is sound shellac, and the cornice can be lightly spirited off and rebodied.

Colour the raw Milliput before blending the new film into the old one. Spirit stains can be used, or a fine artist brush loaded with dilute shellac tinted with earth pigment. Build the tone in thin passes. Match the mid-tone of the mahogany first, then add the darker grain flecks with a fine sable.

When the colour sits correctly, charge a rubber with a 2lb cut of button polish and pull a few small passes over the repaired beads. Work it like a french polishing rubber, but keep the work to the local area. Button polish has an orange cast that suits aged mahogany better than bleached blonde shellac.

Feather the fresh polish over the surrounding original film by a centimetre or two so the repair has no hard edge. Let the film settle, then knock the area back with 0000 grade wire wool and wax to bring the sheen together. Liberon Black Bison in a suitable brown can blend a scratch or a small shade difference across the boundary, which helps the eye travel over the repaired bead-and-reel without stopping on the new work.

Dust at the bench

Milliput dust and old shellac dust are unpleasant to breathe, and uncured epoxy can sensitise skin during mixing and early cure. File over a bench, wear nitrile gloves while kneading, and vacuum the swarf from the work area.

Loose mitres and bubbled veneer beside the loss

Cornices with missing beads have often loosened at the mitres as well, because the knocks that break the bead-and-reel can rack the corner joints. If a mitred corner opens under light pressure, the original animal glue has usually crystallised and released.

Hide glue joint tightening on a loose mitre starts by clearing and softening the old glue. Work warm water into the joint with a syringe over ten or fifteen minutes. Crystallised hide glue will soften enough for the joint to move apart without splitting the mitre. Genuine hide glue is reversible with heat and moisture, which explains both its original use and its ability to be re-softened two hundred years later without solvents.

Re-glue with fresh pearl hide glue heated to around 60C in a glue pot. Keep it close to that temperature, because extra heat reduces strength. Open time is short, under a minute in a cool workshop, so set out the cramp and a rubbed block before the brush touches the joint. Rub the mitre closed to squeeze out excess glue and expel air, then apply light pressure across the corner with a strap or mitre cramp.

Fresh hide glue grabs quickly and reaches handling strength within the hour, although the cornice should sit overnight before the run goes back up. Clean squeeze-out with a hot damp rag while it is still soft. Hardened hide glue can be lifted later with warm water, but catching it wet leaves a tidier arris at the mitre.

Where the cornice sits over a veneered frieze, bubbled veneer near the loose corner needs a different adhesive method. A Titebond veneer repair technique uses a slit cut along the grain with a scalpel, then thinned yellow PVA is worked under the bubble on the tip of a palette knife. A warm iron over baking parchment and a caul weighted overnight pull the lifted veneer back down. Hide glue and PVA can both belong on the same piece, with the original construction deciding which adhesive is used at each spot. After the weight comes off, the remaining uncertainty is whether the lifted veneer still shows a ridge along the grain slit.