From Artwork to Inlay: Commissioning a Custom Floor Medallion

The brief arrives as a JPEG. A compass rose, two metres across, sixteen points, a rendered gradient running from pale to dark on each ray, and a client who has already been shown it. Somewhere between that image and a floor there is a production process with real constraints, and almost every difficult conversation on a bespoke inlay job comes from the same place: the artwork was drawn in a medium where a line has no width and wood has no grain direction.

Custom wood floor inlay medallion marquetry manufacturing is not a mysterious craft, but it is a chain where each step imposes a rule on the step before it. This walks the chain in production order — artwork, vector, cutting, inlay type, fit, finish — and flags what to send, what to ask for, and what to hold back payment against.

What the factory actually needs from your artwork

A mill can cut almost anything. What it cannot do is guess. The gap between "a picture of the design" and "a file that can be cut" is usually three things.

Closed vector regions, not a rendered image. Every piece of the medallion must exist in the file as a closed contour with no gaps, no self-intersections and no stray duplicate paths sitting on top of each other. A traced bitmap will technically open in CAD and will produce hundreds of near-duplicate nodes that the machine follows as a wobble. If the design originated as a raster image, someone has to redraw it. Whether that is your designer or the mill's drafting office is a commercial question worth settling before anyone starts.

A species legend, not a colour render. Each closed region needs a fill that maps to one timber, and the file needs a legend: this fill = black walnut, this fill = Burma teak, this fill = Sonokeling. Gradients do not exist in solid wood. Shading in traditional marquetry is produced by scorching the edge of a piece in hot sand — sand-shading — or by substituting a darker species, and both have to be specified region by region. A rendered gradient with no legend is the single most common reason a first sample comes back wrong.

Grain direction arrows. A sixteen-point compass cut from one board with all the grain running the same way reads flat. The same compass with each ray's grain running radially outward turns and flickers as you walk around it, because the light catches each ray differently. Both are legitimate; only one is what your client saw in the render. Put an arrow in every region of the drawing.

Alongside those, three geometry limits apply regardless of who draws the file:

• Minimum feature width. Fine stringer lines around one millimetre are near the practical floor. Below roughly 0.8 mm, pieces break during handling and glue-up rather than during cutting, which means you lose them after the expensive part of the work is done.
• Inside corner radius. A router cannot cut a corner sharper than half its cutter diameter. A 3 mm bit leaves a 1.5 mm radius in every internal corner. Sharp points either get hand-finished with a chisel, cut on a different machine, or quietly rounded off — and the third option is the one you find out about at sample stage.
• Overall diameter versus panel size. A medallion larger than the mill's press or panel format has to be built in segments with a joint running through the design. Where that joint falls is a design decision, so decide it rather than inherit it.

The accepted file formats and the minimum line width a given mill will commit to are not usually published. Ask for both in writing at the enquiry stage, along with whether there is a design or CAD fee and whether it is credited against a production order.

Cutting the parts: router, laser or hand

Three routes exist and most bespoke medallions use more than one. They differ in the only dimension that matters for fit: kerf, the width of material the cutting tool removes.

Anrantabu runs CNC and hand cutting in the same plant alongside parquet assembly, relief carving and hand-sanding, with over 300 handcraft workers — the practical value of that combination is that a design does not have to be forced onto one machine. The sixteen rays go on the router, the fine acanthus detail gets hand-cut, and the two meet in assembly.

Two things about the laser route that buyers rarely hear until it is too late. The charred edge is carbon, and carbon in a glue line weakens it, so char has to be scraped or sanded off every mating face before assembly — which consumes part of your kerf tolerance. And a char line that survives under a film-forming lacquer can bleed into the surrounding grain under a penetrating oil finish, appearing as a soft grey halo weeks after handover. If the floor is going to be finished with hand-rubbed wax oil, as Anrantabu's flooring is, ask specifically how laser-cut edges are cleaned before glue-up.

Veneer inlay or solid inlay — the decision that outlives the design

This is the choice that determines what the medallion is worth in twenty years, and it is frequently made by default.

The failure mode is specific and worth picturing. A veneer medallion in a hotel lobby comes up for its first refinish in year eight. The contractor sands the floor around it, reaches the medallion, and goes through the picture in three passes. There is no repair — the design is gone. A solid inlay cut to the same depth as the surrounding wear layer sands down with the floor and survives every refinish the floor survives.

Because of that, the maximum useful inlay depth is set by the wear-layer thickness of the base you are inlaying into. Anrantabu sets inlay work into either a solid or an engineered base, but the lamella thickness options are not published, so the depth question has to be asked directly: what is the wear layer on the base you are proposing, and will the inlay be cut to that full depth? The construction decision behind that base is the same one covered in solid, three-layer or multi-layer, and for a large medallion in a mixed-species design an engineered base is normally the flatter answer, because segments with grain running in sixteen directions will otherwise fight each other every season.

Kerf, fit, and the sanding tolerance that decides line or gap

Here is the whole craft compressed into one paragraph. Every joint in a medallion is the meeting of two cut edges. The tool removed material from both. If the pocket in the host panel and the piece that drops into it were cut with the same tool, on the same machine, with a single matched offset applied to both, the joint closes and reads as a drawn line. If the pocket was cut on the router with a 3 mm bit and the insert was cut on the laser at 0.15 mm, the joint has roughly a millimetre and a half of air in it and reads as a gap for the life of the floor.

That is the first question to put to any mill quoting inlay work: are the pocket and the insert cut on the same machine with a matched kerf offset, and what is that offset value? A shop that can answer instantly has done this properly. A shop that has to check has not.

The traditional workaround is worth knowing because good hand shops still use it. In double-bevel cutting, the insert and its host are stacked and cut in one pass with the saw tilted a few degrees off vertical, so the piece cut from the upper sheet drops into the lower sheet's hole and wedges tight — the kerf is absorbed by the bevel. The tilt angle is a function of blade kerf and stack thickness; thin stock with a thick blade needs a steep angle, thick stock with a fine blade barely any. It is slow, it does not scale, and it produces the tightest joints in the trade.

Then there is the finishing tolerance, which is where an otherwise good medallion is lost:

• The assembled medallion is set slightly proud and sanded flush with the surrounding floor. On a solid inlay you may have a millimetre of stock to play with. On a veneer face you have perhaps two or three tenths of a millimetre before you sand through.
• That means the flatness of the panel across the whole medallion diameter has to be held tighter than the sanding allowance. Across a 1.2 m medallion, a low spot in the middle of a fraction of a millimetre becomes a sanded-through ray.
• A joint under roughly a tenth of a millimetre reads as a line. Past about three tenths it reads as a gap, and it will be filled.
• What it is filled with matters. A slurry of sanding dust from the same species mixed with adhesive disappears. A generic coloured filler disappears under lacquer and reappears under a penetrating oil finish, because oil darkens wood and filler at different rates. Ask what the fill material is, and ask to see it on the sample after the oil has cured, not before.

The commissioning sequence, and what to ask the supplier next

Run a bespoke medallion in this order, and pay against these milestones rather than against a single deposit-and-balance split.

1. Send the brief with the artwork, the target diameter, and the base construction. State whether the medallion is field-fit into an existing floor or supplied as a complete panel.
2. Agree the drafting scope, the design fee, and who owns the resulting CAD. Settle the intellectual property question before the first drawing exists — the reasoning in protecting your IP with a China factory applies to a drawing file as much as to a mould.
3. Approve a vector drawing, not a render. Check the species legend, the grain arrows, minimum feature widths and inside radii on that drawing.
4. Approve a physical sample. For a large medallion, a representative segment at full thickness and full finish is usually enough. Confirm the turnaround for this before committing, since a bespoke sample cycle sits inside the project schedule rather than beside it. Treat it with the same formality as any sample approval process: sign it, photograph it, keep the retained half.
5. Fix the tolerances in writing. Maximum joint gap, panel flatness across the diameter, fill material, and the finish system.
6. Ask for the routing template. A medallion supplied with a matched template so the installer cuts the host hole to the same offset removes the biggest single site risk. Scribing by hand on site is where good medallions get ruined.
7. Inspect before shipment, dry and assembled. Look across the face at a low angle under a raking light, not from above under a work lamp.

Two closing questions for the enquiry email: what file formats do you accept and what is your minimum cuttable line width; and what is the realistic drawing-to-approved-sample turnaround for a design of this complexity. Neither is published, both are decisive for your programme.

If you want to start from something already drawn rather than from a blank sheet, Anrantabu Flooring keeps a library of over 1,500 proprietary parquet patterns — designs, not filings — and develops bespoke designs to buyer specification, cutting inlay work in contrasting species including Burma teak, black walnut, rosewood, Sonokeling and cedar. Picking a library pattern and modifying it is usually faster and cheaper than drafting from zero, and it gives you a physical reference to point at during approval. For how the surrounding field is built, the Versailles panel construction covers the module the medallion has to sit inside.