Cabinet Grade Plywood; Ultimate Guide

Cabinet-grade plywood is a general term for any hardwood plywood used to manufacture cabinets or furniture cabinetry. While this can refer to specific hardwoods, such as oak, maple, and cherry, plywood is listed only as “cabinet grade” without mentioning the particular hardwood veneer. These cases typically refer to less expensive hardwoods, such as birch or mahogany.

What qualifies plywood as being considered “cabinet grade” is the quality of the veneer surfaces, nothing more. These faces are graded differently than softwood plywood, with a grading provided for both faces. The “good” or visible face is letter-graded, while the back face is number-graded.

The quality of the veneer and the type of wood it is made of is defined as a particular piece of plywood being “cabinet grade” rather than structural grade. Due to the cost difference, you’d never want to use cabinet-grade plywood for structural work.

Visible Face Grades:

• AA – Good or good sequence
• A – Good
• B – Good, sliced B, RC sound
• C – Rotary cut solid

Back Face Grades:

1. Sound, same species, specifically cut
2. Solid, same species, specifically cut
3. Rotary Grain
4. Reject Back

The plywood is marked to indicate both the front and back of the sheet, such as A2, which indicates an A grade on the face side and a 2 grade on the backside. Grades A1 and A2 or above are considered good for staining and varnishing. Grades B3 and below are paint-grade plywood products.

Not all veneers used for plywood faces are created equal.

Be aware of the following:

• quality of the veneer
• thickness
• the way it is cut

High-quality cabinet-grade plywood usually has face veneers about 1/40″ of an inch thick. While that isn’t much, it’s much better than the lower grades, which will have face veneers only 1/100″ thick. Great care must be taken when sanding this veneer, as it is easy to sand right through it.

Another important consideration is how the face veneer is cut. It can either be rotary cut or plain-sliced, and this will greatly affect its appearance.

Rotary-cut plywood is cut on a huge lathe. A log is placed on the lathe. The wood is peeled off in one long veneer sheet, as wide as the log and as long as possible. That sheet is then cut up and used as the core or face veneer for plywood.

This is why common structural plywood doesn’t have much of a grain pattern. That pattern comes from cutting across the log’s rings, but this means of cutting rarely crosses the rings. All structural grade plywood and the core veneers of hardwood plywood are made this way. Face grade C and back grade 3 are rotary cut. They are only used for applications where the finished item will be painted.

The plain-sliced veneer is cut like boards, cutting across the tree’s rings, which allows the gain pattern to show. It can be life-sawn, plain-sawn, or quarter-sawn and is much more attractive. It provides the contrast in grain color that makes many hardwoods attractive. Hardwood with plain-sliced veneer is preferred for furniture and fine cabinetry, where the plywood is stained and varnished.

The best cabinet-grade plywood will not only use plain-sliced veneer for the face side but also book-matched veneer, providing the most attractive gain patterns. Careful project planning and layout for cutting are necessary when using these grades of plywood to get the maximum benefit out of the book-matched grain.

Cabinet Grade Plywood Thickness

Cabinet-grade plywood comes in thicknesses ranging from 1/4″ to 3/4″. Generally speaking, 3/4″ thick plywood is used the most for cabinetwork, although thinner plywood may be used for furniture, including dressers. The thicker plywood is used for cabinets to provide stiffness and strength. Cabinets are expected to last for a long time, so it might seem that the plywood thicknesses called for in project plans are excessive. This is done intentionally to provide strength and stiffness.

Generally speaking, the only place 1/4″ thick plywood is used is in drawer bottoms, where a rabbeted groove is cut into the drawer sides to hold the bottom and provide support. If the drawers are being used to hold heavy items, then 3/8″ thick plywood should be used for the drawer bottoms. Sides are often made of 1/2″ thick plywood, with ¾” thick plywood or hardwood boards used for drawer fronts.

Cabinet face framing and sides are almost always ¾” thick plywood, although it is possible to make the sides of cabinets out of 1/2″ thick plywood when using a raised or recessed panel design. In that case, 3/4″ plywood is used for the outer frame of the sides, with the thinner plywood used for the panel.

Shelves should always be made of 3/4″ thick plywood, which isn’t always on commercially manufactured furniture and cabinets. Thinner plywood, MDF, or particle board, often used for shelving, is not strong enough to support the weight often stacked on these shelves, especially for a prolonged time. The shelves bow with time, causing storage problems and making the cabinet unattractive.

Adding a lip to the front or both the front and back of the shelf can make it stronger and longer-lasting. The lip, which is normally made of hardwood, works like an I-beam, increasing the effective thickness of the shelf to fight against any deflection (bending).

When Buying

When choosing cabinet-grade plywood for a particular project, it is important to consider the quality of the two faces. While in some applications, such as a carcase (the casing of a dresser), the back side of the plywood won’t be visible,in other kitchen cabinet doors, the back side will be seen whenever the door is opened. Therefore, kitchen cabinets aren’t considered in the same class as fine furniture, so the grade of plywood used may have to be higher.

When selecting plywood for a project, you want all of your plywood coming from the same mill. Suppose you were to build a set of kitchen cabinets, where half of the plywood was freshly bought, and the other half had been sitting in your workshop but had come from a different mill. In that case, the plywood might be of various thicknesses, even though the nominal thickness is the same.

This difference is not intentional but results from how the plywood is manufactured. In any plywood manufacturing process, the plywood is put under pressure while the adhesive or rosin that holds the veneers together is set. The compression can vary depending on the wood types used in the veneers, their moisture content, and the type of rosin or adhesive used. This results in the finished pieces varying slightly in thickness from batch to batch and mill to mill.

How to Buy the Good Stuff

When looking to buy cabinet-grade plywood, there are three things you should look for:

• The face veneer – How thick is it, what does the grain look like, and is the grain book matched. Any cabinet-grade plywood to be stained or varnished should look like boards laminated together, not plywood.
• The overall flatness – All plywood will have a slight curvature in the sheet. However, you don’t want it to be extensive. An excessive bend or warp indicates problems with the core. These will not come out as you assemble your project. But will apply constant pressure, which could lower the life of the finished product.
• The edge – When looking at veneer core plywood, the more layers of veneer there are, the better quality it is. Hardwood cores are always better than softwood ones, even if low-grade hardwoods are used. Check how straight the lines of the rosin or adhesive are, as that will indicate how much of a likelihood there is of a problem in the core affecting the look of the face veneer.

While you can buy cabinet-grade plywood from your local home improvement center, the selection will be limited. Their inventory consists mainly of structural softwood plywood, with only a few types of cabinet-grade plywood thrown in. Unless you are willing to allow them to dictate the materials you use, you are probably better off going elsewhere.

The best selection and quality cabinet grade plywood will come from businesses specializing in selling architectural trim. Even then, they will not have every grade and type of cabinet grade plywood available. You may need to visit several of these businesses in your area, to find the best cabinet grade plywood for your product.

Suppose you are fortunate enough to have a lumber yard that specializes in carrying hardwoods for woodworkers. In that case, chances are that they will also bring a good selection of hardwood plywood, allowing you a more incredible choice for your projects.

Core Types

In addition to the face grades used, cabinet-grade plywood is also graded by the type of core used in its manufacture. Depending upon the manufacturer, several different core types are available, each with its characteristics and qualities:

• Veneer core (V/C) – This is the standard plywood core, with an odd number of layers of veneer laid at 90-degree angles to each other. The actual number of layers can range anywhere from 3 to 11, depending upon the plywood sheet’s thickness and the plywood’s quality. Generally speaking, the more layers, the higher quality the plywood is considered to be. One risk with veneer core plywood is that imperfections can easily “telegraph” to the face layer, showing as indentations or stains in the finish. This is especially true with thin face veneers.
• Fibercore (MDF) – The entire core is a single medium density fiberboard (MDF). This tends to produce the most stable panel. The panel is extremely machineable with no voids. The fiber cores smooth surface provides a superior face and back veneer finish core. The only drawback to MDF is its high weight.
• Pro–Core – A new “pro-core” is available from some manufacturers. This combines layers of hardwood veneer with layers of MDF. In doing so, it adds structural strength that the MDF is lacking, while keeping the smooth, flat surface of the MDF for the veneer to be glued to. The veneer cores will be towards the inside, with the MDF layer just below the face veneer.
• Particleboard Core (PBC) – This is similar to MDF, except for having a particleboard core, instead of MDF. Like the MDF, PBC provides a smooth surface for the veneer’s finishing. However, it is nowhere near as strong as MDF.
• Lumbercore (LBC) – This is a five ply construction, with two thin veneers (the face veneer and one backup layer) on either side of the lumber core. The core is made of a series of edge-glued strips of lumber, ranging from 1-1/2″ to 2″ in width. This core type is only found in hardwood plywood that is 3/4″ thick or thicker. It provides a plywood extremely resistant to buckling, twisting, and warping.

While veneer core is the most commonly found core used in cabinet grade plywood, the more stable a core is, the higher a grade it is considered to be. Therefore, fibercore and particleboard core are considered the highest quality cabinet plywood. This quality, of course, reflects in the price of the plywood, but it provides for a better finished product.

However, veneer core plywood is more vital than MDF or PCB core. So, the same project may use both, with MDF core plywood on the facing side of the cabinet and veneer core plywood for the back and sides, where any imperfections telegraphing through the face veneer won’t be obvious.

Architectural Woodwork Institute Quality Standards prohibit veneer core plywood for some items. For example, cabinet doors, where any printing of imperfections in the core will become highly visible on the exterior of the finished product.

Baltic Birch

It is rare to find core veneers made of the same type of wood as face veneers. The raw material costs are such that manufacturers try to use lower cost veneers for the core of their plywood. Baltic birch is one of the few cabinet-grade plywood types that may still have a matched wood core. There are no voids in this plywood, even in the core layers.

By using the same type of wood for the core veneers, as is used for the face veneer, these manufacturers produce a cabinet grade plywood that is structurally strong and extremely stable. The face veneer tends to be thicker, allowing you to sand it without worrying about sanding right through.

This is a European product rather than an American one. So the sheet size is approximately five foot square, a bit different than what we’re used to. The 1.5mm thickness on the veneer layers makes for strong plywood that is excellent for joinery work. On average, it is also considerably flatter than other cabinet grade plywood. Often used to build furniture with the edge of the sheets exposed, providing a much more attractive appearance than the edge of most other plywood.

Prefinished Cabinet Grade Plywood

Some manufacturers now provide prefinished cabinet grade plywood, where the staining and varnishing are already done for you at the mill. This is primarily done for major cabinet manufacturers, where they don’t want to bother with finishing operations. But it can provide the same benefits to the small-time cabinet shop, the contractor, or the hobbyist who doesn’t want to deal with finishing.

Finish operations tend to be time-consuming, especially if you want fine finishes. In construction, it has become increasingly common for the painting subcontractor to receive the architectural trim, doors, and windows at his shop for finishing before they are installed in the home. This saves labor time and costs for the painting contractor and makes it possible to provide a consistent finish throughout the home. Providing a consistent finish in the workshop is much easier than with the trim scattered throughout the home.

If anything, the high volume of finishing work produced in prefinished plywood will generate an even more consistent product because of the methodology used. Factory-type operations lend themselves to great consistency, reflecting the finished project’s appearance.

These same concerns apply to cabinet-grade plywood used in any project. Purchasing prefinished panels saves time and money while giving yourself a more consistent finish on the project.

Cutting Cabinet Grade Plywood without Splintering

If you’ve ever worked with plywood, you’ve probably had more than one cut sheet that splintered badly when cutting it. This is likely to happen anytime you are cutting across the grain. Since we can’t avoid cutting across the grain, it’s good to have a method to protect the expensive veneer surface and provide us with a clean cut.

To start with, you need a blade designed for use with plywood. Regardless of the kind of saw, the blade that came is not designed specifically for plywood; it’s a general-use rip blade. That’s not what you want. Investing in a quality plywood blade is worth it. The more teeth the blade has, the smoother a cut it will provide. However, a high tooth count also means cutting slower, as each tooth takes a smaller chip.

Always use a sharp blade. Once you get used to a quality plywood blade, you will recognize when it gets dull, as it will be even more likely to splinter. It’s time to change the blade, sending your old blade off for resharpening.

Be sure that as you cut, your plywood’s face side is towards the blade’s outer perimeter. This means you want the face side up when using a table saw and down when using a circular, radial arm, or miter saw.

Finally, add a strip of masking tape right over the cut line, on both sides, before cutting. This will help hold the wood grain together rather than splitting. Cut smoothly, maintaining the same speed. Remove the tape when your cut is finished so the adhesive doesn’t stain or stick to the wood.