How to Copper-Plate a Model Ship Hull

From the later 18th century, many sailing warships and some merchant ships had the underwater part of the hull sheathed in thin copper plates. The copper protected the planking from shipworm and slowed the growth of weed and barnacles, which kept ships faster between refits. On a model, a coppered bottom adds colour and a lot of fine detail, and it is one of the most satisfying jobs on a period ship.

It is also slow, repetitive work. A large ship model can need thousands of plates. This guide covers the choices to make before you start, how to plan the layout, how to lay the plates, and how to clean and finish them.

Does your model need copper plating

Check before you buy anything. Copper sheathing was not used on every ship, or in every period:

• The Royal Navy trialled copper sheathing in the 1760s and adopted it widely across the fleet by around the early 1780s. Ships from earlier periods were usually not coppered.
• Many merchant ships, smaller craft and ships of other navies were not coppered, or were coppered at different dates.
• A single ship could be coppered at one point in its career and not another. Some ships also used other metals or alloys later in the 19th century, such as the Muntz metal on the Cutty Sark.

Your plans, the kit instructions or a good reference book on the ship should tell you. If the ship you are modelling was coppered at the date you are depicting, plate it. If you can’t find out, a painted bottom in the colour the period suggests is a safe choice.

Options for the plates

Kit copper plates

Many kits for coppered ships, such as USS Constitution kits, include pre-cut plates, often with a nail pattern embossed into them. Some are self-adhesive. Others need glue. They are the easiest way to get a convincing result, and the nail detail is consistent from plate to plate. Aftermarket packs are sold in several scale sizes if your kit doesn’t include them or you are scratch building.

Self-adhesive copper foil tape

Copper foil tape, sold for stained glass work and electrical shielding, comes in rolls of various widths. Choose a width close to the scale plate width, cut it into plate-length pieces with a scalpel and steel rule, and stick them down. It is cheap and quick. You can add nail detail by running a dressmaker’s tracing wheel, or a similar pounce wheel, along the back of the tape on a soft surface such as a cork mat before you peel and stick it.

Burnish each plate down firmly. Some builders report self-adhesive foil lifting at the edges over time, so a coat of lacquer over the finished plating can help hold it.

Thin copper sheet

Thin copper sheet or shim can be cut into plates and glued down. It gives the most control over plate size and thickness, but it is the most work: each plate is cut by hand, and you will need to emboss nail detail yourself if you want it.

Paint

You don’t have to use metal at all. Copper paint, or a coppery base coat with a wash to suggest plate edges, is common on small-scale models, plastic kits and models where plating would be too fine to see. Some builders mark faint plate lines with a sharp pencil or by scribing before painting. Paint avoids the time and cost of plating and still reads as a coppered bottom from normal viewing distance.

How big should the plates be

Plate sizes varied, but a commonly quoted size for Royal Navy sheathing plates is about 4 ft by 14 in (roughly 1220 mm by 355 mm). At common model scales, that works out to approximately:

If your plans or kit give a plate size, use that instead. Below about 1:96, individual plates get very small and the work becomes extremely fiddly. Many builders switch to paint at that size.

Tools and materials

• plates, foil tape or sheet
• a sharp scalpel or craft knife and spare blades
• a steel rule and a small square
• tweezers, for placing plates without touching them
• a burnishing tool, such as a smooth rounded handle, a bone folder or the back of a spoon
• adhesive, if your plates aren’t self-adhesive
• thin disposable gloves, to keep finger oils off the copper
• isopropyl alcohol and lint-free cloth, for degreasing
• masking tape and a way to mark the waterline (see below)
• a tracing wheel, if you are adding nail detail yourself

On adhesive: thin contact cement and gel cyanoacrylate (CA) are the usual choices. Use CA very sparingly. Excess squeezes out at the plate edges and is hard to clean off, and CA fumes can leave a white haze (blooming) on nearby surfaces. Test any adhesive on a scrap plate first.

Preparing the hull

Copper plates are thin and show every lump and hollow underneath them. The hull below the waterline needs to be as smooth and fair as you can make it before plating starts.

• Finish the planking and fill any gaps. Our guide to planking a wooden model ship or yacht hull covers getting a smooth planked surface.
• Sand fair with long sanding blocks and check under raking light. If the hull has bumps that come from the framing, fix them at the source. See how to fair bulkheads before planking for building a fair hull from the start.
• Seal the wood and lightly sand. Some builders then paint the bottom a copper or brown colour, so any tiny gap between plates doesn’t show bare wood.
• Fit anything that must go on before the plates, such as the stem, keel and sternpost, and decide whether the rudder will be plated on or off the model.

Mark the waterline

The top edge of the copper follows the waterline, so mark it accurately before you plate. Our guide to masking and painting a straight waterline covers marking methods in more detail. Set the hull level on a stand or jig, fore and aft and side to side. Then use a pencil held at a fixed height in a block, a scribing gauge or a height gauge, and run it around the hull to draw the line. Many references show the copper stopping at or slightly above the load waterline. Check your plans for where it should end on your ship.

A strip of thin masking tape along the line makes a clean top edge for the top row of plates.

Planning the layout

Overlap direction

On the real ships, plates overlapped slightly at their edges. On a model, the overlap is usually very small or the plates are simply butted together, since the plates are already much thicker than scale.

A common modelling approach is:

• Work from the stern forward, so each plate slightly overlaps the plate behind it. The exposed edges then face aft, the way water flows past the hull.
• Work from the keel upward, so each row slightly overlaps the row below it.

Sources and kit instructions don’t all agree on the details of real-ship practice, and it varied over time. If your plans or instructions specify an order, follow them. Whatever you choose, be consistent over the whole hull, and do the same on both sides.

Where the rows meet

Rows of plates can’t follow the waterline all the way down to the keel, because the hull’s shape changes too much. A common pattern is to plan two sets of rows:

1. Lower rows run parallel to the keel.
2. Upper rows run parallel to the waterline.

The two sets meet along a line running diagonally along the hull, often lower amidships and rising toward the bow and stern. Plates along that meeting line are trimmed to fit the rows on either side. Photos of contemporary models and museum ships are a good guide to where this line falls.

Before starting, mark out the rows with masking tape strips the width of a plate: the lower set measured up from the keel, the upper set measured down from the waterline. This shows where the meeting line will fall and how the rows run around the turn of the bilge and at the bow and stern, before you commit any copper. The tape lines also act as guides while you lay the plates.

Laying the plates step by step

1. Degrease the hull below the waterline with a lightly dampened cloth of isopropyl alcohol, and let it dry. Put on gloves.
2. Start the first row at the keel, at the stern. Lay the first plate, burnish it down, and work forward along the keel.
3. Do the same on the other side before moving up. Keeping both sides in step makes it easier to match them.
4. Stagger the joints. Offset the end joints of each row from the row below, the way bricks are laid, so you don’t end up with joints lined up in one long seam.
5. Work up through the lower set of rows, following your tape guides, until you reach the meeting line.
6. Trim plates at the meeting line so they fit neatly against the first row of the upper set. Score and snap, or cut with a fresh blade on the hull itself, being careful not to cut into the plates below.
7. Carry on up through the upper set, following the guides that run parallel to the waterline, keeping the same overlap direction as the lower rows. Finish with the top row, its top edge on your masking tape line at the waterline.
8. Trim around the stem and sternpost. Plates curve tightly here. Small plates and careful burnishing help. On the real ships, plates were often folded around the stem and keel edges.
9. Burnish everything firmly once each section is done, paying attention to plate edges.
10. Remove the masking tape along the waterline.

Change scalpel blades often. A dull blade tears foil and drags thin plates out of shape. Work in sessions. Plating is a task where fatigue leads to crooked rows.

Rudder, stem and keel

• Rudder: Many builders plate the rudder off the model, so it is easy to handle, then refit it. Plate both faces and the edges, and check that the hinges (pintles and gudgeons) still fit afterwards.
• Keel: Plate the sides and decide, from your references, whether to cover the bottom of the keel. Many models plate both sides with plates wrapping slightly underneath.
• Stem and sternpost: Wrap plates around the leading edge of the stem as far up as the copper goes, trimming them to a neat edge.

Cleaning and finishing the copper

Keeping it bright

Most finished plating looks patchy at first, with fingerprints, adhesive and some tarnish. A thread on the DeAgostini model-building forum about cleaning plating before lacquering gives some sound advice:

• Avoid cream cleaners. They lodge in the joints between plates and dry looking like grout.
• Be careful with liquids. They can creep under the plates and lift them, or leave residue in the joints.
• For surface tarnish, try a dry copper-cleaning cloth or a wadding-type metal polish, used gently.
• Then wipe with alcohol to remove grease and residue, and use a tack cloth to remove lint.
• Lacquer to seal the copper and stop it tarnishing. A matt or satin lacquer tones down a very bright, new-penny look.

As the same thread recommends, test any cleaner and lacquer on a scrap piece of plating first.

Weathered copper

Copper on a working ship didn’t stay bright for long. It dulled to a brownish colour in service, and older copper could show greenish streaks. If you prefer that look:

• Let it tarnish naturally before lacquering, or don’t lacquer at all.
• Darken it chemically. Copper patina solutions sold for metalwork darken copper quickly. The forum thread notes that salt with lemon juice or vinegar will also age copper and turn it brown. Test first, rinse well and let it dry completely, since trapped chemicals can keep working under the plates.
• Use washes of paint to add tone and green streaks, then seal with a matt lacquer.

Bright and weathered copper are both widely used on display models. Choose the look you like, and keep it consistent with the rest of the model’s finish.

Common problems

• Rows drifting off line. Check rows against the keel or waterline every few plates with a strip of tape or a flexible rule, and correct early by trimming a plate slightly.
• Bumps showing through. The hull wasn’t smooth enough. Small dents can sometimes be eased by burnishing. Larger ones need the plate lifted and the surface underneath sanded or filled.
• Edges lifting. Burnish them down again. If self-adhesive plates keep lifting, a tiny amount of adhesive under the edge, then lacquer over the top, usually holds them.
• Glue stains or haze. Use less adhesive and remove excess straight away. Haze from CA can sometimes be polished off gently, but it’s easier to avoid.
• Fingerprints. Wear gloves and handle plates with tweezers. Fingerprints tarnish faster than the rest of the copper and can show as dark marks later.
• Sides that don’t match. Plate both sides in step, row by row, and compare them often from directly ahead and astern.

For where coppering fits among the other hull-building stages, see our overview of making a model boat hull.