Veneer grades and supply forms

How veneer is supplied

Veneer comes in very different forms. The most common are sheets, rolls, edge banding and bundled flitches. Each has its own purpose, and for handmade veneer work and geometric intarsia not every format is equally suitable; the differences are not always clear from the product name.

The format decides how the veneer is stored, cut and worked. A format made for furniture production can be wrong for precise freehand cutting with a scalpel; one made for large surfaces can be wasteful or even troublesome for small geometric objects. The right format makes the work easier and more precise and wastes less material.

Sheets

Sheets are the main form for handmade veneer work. They are cut flat and supplied in stacks taken from a single part of a log. Typical sizes range, depending on species and cut, from 15 to 40 cm wide and 60 to 120 cm long. Exotic woods from narrow trunks, such as wenge, often come in narrower sheets than species that grow wide.

Sheets from one flitch are numbered and follow one another in their figure. Neighbouring sheets share almost identical colour, density of grain and arrangement of pores, which makes them ideal for patterns with several pieces of the same wood, because the look stays consistent across the whole pattern.

For geometric intarsia, sheets are the right format. They lie flat, have no curl from a roll and can go straight onto the bench. Precise freehand cutting, laser work and CNC all need veneer that lies flat.

Rolls

Veneer on a roll is usually very thin material, wound up for machine processing or large glued surfaces, and often backed with fleece or paper so that the thin veneer can be handled without tearing as it unrolls.

For intarsia, rolled veneer is as a rule unsuitable. The main reason is the curl: unrolled material wants to roll up again and does not lie flat, and even after weighting or pressing some tendency to curl remains. Precise cutting and flat assembly need a stable starting point, and a piece that curls away while you cut gives inaccurate edges.

The fleece or paper backing common on rolls is another drawback: it interferes with the glue bond at the joint and can affect the depth of the joint. Buying rolls often means buying a format optimised for coating furniture, not for handmade intarsia.

Edge banding

Edge banding is a narrow strip of veneer with hot-melt glue on the back, developed for edging boards and furniture. Widths of 19 to 50 mm are common. It is applied with an iron or an edge-banding machine; the glue melts with the heat and bonds to the edge of the board.

Edge banding is not suitable for intarsia. The glue on the back makes precise freehand cutting difficult, because the material sticks or tears as the friction of the cut warms it. It is too narrow for larger areas of a pattern, and there is no continuity of figure across several cuts. It is an industrial product with a defined purpose that has nothing to do with geometric intarsia.

Beginners sometimes buy edge banding because it is sold cheaply as veneer in DIY stores. The result is poor cut edges, material breaking at angles and problems with glue in the press. For serious intarsia, buy sheets directly from a veneer dealer.

Flitches and bundles

A flitch or bundle is a group of sheets cut in sequence from the same part of a log and packed together. The sheets in a flitch are numbered, and the number shows their relative position: sheet one and sheet two are neighbours, sheet one and sheet thirty can look visibly different.

For intarsia that uses one species in several fields, choosing from the same flitch is decisive. Two sheets of the same species from different flitches can differ noticeably in colour, density of grain and reflection. This is especially clear with walnut, whose ground colour ranges from creamy beige to dark brown, and with ash, which ranges from almost white to yellowish brown.

When buying, note the flitch number or at least the date of delivery. If you later need more material for repairs or for further pieces of the same object, matching it from the same flitch or an equivalent batch is easier when those details exist.

Raw veneer and backed veneer

Raw veneer is plain wood with no coating or laminate on the back, supplied as it comes from the log. Backed veneer has a layer of paper, fleece or phenolic resin that makes it easier to handle and less likely to split.

For geometric intarsia, raw veneer is almost always right. The glue bond is more direct, with no backing between the wood fibres and the glue, and cuts at angles and tight curves are cleaner, because no laminate with a different cutting behaviour has to be cut along with the wood. Raw veneers from good suppliers are also thicker and more stable than the thin backed veneers used for simple coating.

Backed veneer has its place: it is easier to handle on large surfaces, less prone to tearing in transport and can be tacked down with an iron. In intarsia, though, its drawbacks outweigh those advantages, and if you do use it, you have to adjust the depth of the joints and the amount of glue.

Thicknesses and what they mean

Commercial raw veneers for decorative work are typically 0.5 to 1.2 mm thick. The most common in intarsia are 0.6, 0.7 and 0.9 mm; some suppliers also offer 1.0 or 1.2 mm, preferred for strongly textured species or for cutting by hand.

Thickness affects four things: how the veneer cuts, how much room there is for sanding, the geometry of the joints and how flat it stays. Thinner veneer allows finer lines but leaves less material for sanding; thicker veneer allows more sanding but has a larger joint face that must glue completely in the press. On small objects such as the THINK BIGGER pen holder, an even thickness across all the veneers matters especially, because differences in height show directly.

Veneers from different suppliers or species do not automatically have the same nominal thickness. If you combine two species in a pattern, measure both deliveries before cutting. A difference of 0.2 mm between two sheets leaves a step after pressing that needs extra sanding and costs geometric sharpness.

Stability, flexibility and the risk of splitting

Very thin veneer under 0.5 mm is flexible. That can help when coating curved shapes, but in geometric intarsia with many straight edges and sharp angles flexibility is a risk: a flexible piece does not lie flat and can tip while you cut. At sharp angles, under thirty degrees for example, thin veneer splits along the grain when the cutting pressure exceeds its strength.

The risk depends on the species. Wenge splits lengthwise very easily, because its fibres are coarse and straight with little cross-connection; oak splits less readily. Thin wenge veneers under 0.6 mm are risky in geometric intarsia with sharp angles and small fields, so with wenge, 0.7 to 0.9 mm is the safer choice.

Stability also depends on storage. Veneer that has settled to the moisture of the workshop behaves more predictably than freshly delivered material still adjusting to it, so let veneer acclimatise in the workshop for a few days before using it.

Storing sheets

The supply form also decides how veneer is stored. Sheets lie flat on a level board, covered and evenly weighted, away from sun and heating. A sheet that lay curved or rolled for a few weeks keeps that shape, especially when it is dry and brittle; if you receive rolled veneer and will not use it for months, unroll it soon and store it flat from the start. The climate, acclimatising, protection from light, sorting offcuts and labelling stacks are covered in storing veneer.

Which format for which way of working

• Geometric intarsia cut by hand: flat raw sheets, 0.6 to 0.9 mm, from the same flitch. No rolls, no backed veneer, no edge banding; consistency of figure within each species comes first.
• Small desk objects: smaller sheet sizes are enough and use material more sparingly. Offcuts from other projects can be used as long as thickness and character match; mixed thicknesses are the biggest risk with offcuts.
• Laser cutting: raw veneer without a backing works best. Paper backing burns unevenly and leaves residue at the kerf, phenolic backing gives off harmful fumes, and smoke has to be extracted well in any case. Thinner veneers cut faster with a narrower burnt edge; thicker ones need more power or several passes.
• CNC: routers can also handle thicker veneer (0.9 to 1.2 mm), but suction and vibration can lift thin sheets, so flat clamping with a vacuum table or adhesive film is essential. A backing can make holding easier but still interferes with the joints in assembly.
• Wall panels and larger areas: larger sheets, book-matched flitches and consistent choice of flitch. Here consistency of colour across large areas matters more than on small objects, where the viewer judges single joints rather than the whole surface.

How beginners often buy the wrong veneer

Most buying mistakes are not about species but about supply forms:

• Edge banding from a DIY store bought as a cheap start. It is too narrow, has a glue backing and does not cut precisely; the first pieces fail, and the technique gets the blame instead of the material.
• Rolls from online marketplaces ordered because they are cheap and plentiful. Unrolled, they curl, the pieces do not lie flat and the first cut goes wrong; flattening them in the workshop without control of moisture and heat often lets the curl come back after pressing.
• Sheets from different deliveries mixed. Two sheets of the same species from different sources look alike in storage, but under the finish the difference in colour stands out at once. When buying for a particular project, buy everything at once, from one batch.
• Thin veneer of a coarse-fibred species such as wenge ordered because the list said so. The pieces split at the tips of angles and will not assemble cleanly. Every species has its own minimum working thickness, depending on the cutting method and the angles of the pattern.

Consistency of grain and colour

Consistency of grain describes how even the run of the fibres is across a sheet. A sheet with very even, parallel grain cuts predictably and reflects light evenly; one with knotty, wavy or irregular grain behaves differently when cut and reflects light differently in different places, even within the same pattern.

Consistency of colour describes how even the ground colour is across a sheet and between sheets of a flitch. Natural variation is unavoidable, and small differences within a species are acceptable in intarsia as long as the contrast between species dominates. It becomes a problem only when the variation is so large that some fields look lighter or darker than their neighbours of the same wood.

That check is best done before cutting: lay the sheets side by side under workshop light and compare them. It takes five minutes and can save corrections that are no longer possible after pressing.

How Reihax chooses veneer

For small geometric objects, flat raw sheets without a backing work best. Reihax works with wenge, oak, ash, walnut and mahogany, plus maple and cherry. Where possible, new stock of a species comes from the same source as what is already there; where that is not possible, the material is judged on the veneer itself. The Reihax mahogany, for example, came from a workshop closing down, without a botanical name, and was judged on colour, thickness, flatness and how it cuts (judging veneer quality).

For small batches, consistency counts for more than a low price. A lot that does not match the existing stock in colour or density of grain makes the second piece of a series look visibly different from the first, so it pays to compare before buying: a new sheet of wenge that is clearly lighter than the last changes the contrast of the whole pattern. The comparison is made under the light the object will later be seen in.

For small precise work, veneers with calm, straight grain are the more predictable choice (types of veneer and cuts). Species prone to splitting, such as wenge, are safer from about 0.7 mm; below that, angle tips under thirty degrees become risky. Light woods such as ash and oak still work well at 0.6 mm, because their fibres hold together better across the grain.