What Are Sheet Goods? Plywood, particleboard, MDF, and melamine explained…

The basic structural component of cabinetry is some form of sheet goods; most frequently plywood.  Other commonly used sheet goods are particleboard, fiberboard, melamine panels and hardboard.

These materials come in handy when you need to cover a broad project area without including seams. Sheet goods are dimensionally stable (there is no substantive wood grain to contend with) and relatively inexpensive, when compared to the price of solid lumber. You’ll turn to them time and time again for different woodworking applications.

Here is an overview of the options you’ll find at most home centers lumberyards:

Plywood: is fashioned from sheets of wood veneer, primarily pine and fir. By orienting the wood grain of each laminated sheet so adjacent sheets are perpendicular, the product is able to withstand greater stress than construction lumber of the same thickness. In addition, it is more dimensionally stable.

Most lumberyards stock furniture-grade plywood in several thicknesses and face veneer options (pine, red oak, birch and maple are the most common face veneers). Lumberyards can order plywood with dozens of additional veneer options.

Choosing the right plywood for your woodworking project is an important task. In addition to the various core, thickness and face veneer options, you’ll also need to make a decision on the plywood grade. 

Basically, there are two grading systems in use today. The one most people are familiar with is administered by the APA (Engineered Wood Association, formerly the American Plywood Association). The APA grade stamps are found on sanded plywood, sheathing and structural (called performance-rated) panels.

Along with grading each face of the plywood by letter (A to D) or purpose, the APA performance-rated stamp lists other information such as exposure rating, maximum allowable span, type of wood used to make the plies and the identification number of the mill where the panel was manufactured.

Many hardwood-veneer sanded plywood panels are graded by the Hardwood Plywood and Veneer Association (HPVA). The HPVA grading numbers are similar to those employed by APA: they refer to a face grade (from A to E) and a back grade (from 1 to 4). Thus, a sheet of plywood that has a premium face (A) and a so-so back (3) would be referred to as A-3 by HPVA (and AC by APA)

Particleboard: possesses several unique qualities that might make it a good choice for your next built-in project particularly if the project includes a counter or tabletop. Particleboard is very dimensionally stable (it isn’t likely to expand, contract or warp); it has a relatively smooth surface that provides a suitable substrate for laminate; it degrades when exposed to moisture; it’s too coarse in the core to be shaped effectively; and it’s heavy.

Medium-Density Fiberboard (MDF): is similar to particleboard in constitution, but is denser and heavier. The smoothness and density of MDF make it a good substrate choice for veneered projects; the rougher surface of particleboard and most plywoods do not bond as cleanly with thin wood veneer. You can even laminate layers of MDF to create structural components that can be veneered or painted. MDF is also increasing in popularity as a trim molding material.

Melamine Board: is fashioned with a particleboard core with one or two plastic laminate faces. Thicknesses range from ¼ and ¾ inch. Stock colors at most lumber yards and building centers generally are limited to white, gray, almond and sometimes black. The panels are oversized by 1 inch (a 4 X 8 sheet is actually 49 X 97 inch) because the brittle melamine has a tendency to chip at the edges during transport. Plant to trim fresh edges.

FACE GRADE DESCRIPTIONS

N Smooth surface “natural finish” veneer. Select, all heartwood or all sapwood. Free of open defects. Allows not more than six repairs, wood only, per 4 X 8 panel, made parallel to grain and well-matched for grain and color.

A Smooth, paintable. Not more than 18 neatly made repairs, boat, sled or router type, and parallel to grain, permitted. May be used for natural finish in less demanding applications. Synthetic repairs permitted.

B Solid surface. Shims, circular repair plugs and tight knots to 1 inch across grain permitted. Some minor splits permitted. Synthetic repairs permitted.

C plugged Improved C veneer with splits limited to 1/8 inch width and knotholes and borer holes limited to ¼ X ½ inch admits some broken grain. Synthetic repairs permitted.

C Tight knots to 1 ½ inch knotholes to 1 inch across grain and some 1 ½ inch if total width of knots and knotholes is within specified limits. Synthetic or wood repairs. Discoloration and sanding defects that do not impair strength permitted. Limited splits allowed. Stitching permitted.

D Knots and knotholes to 2 ½ inch across grain and ½ inch larger within specified limits. Limited splits are permitted. Stitching permitted. Limited to interior and exposure 1 or 2 panels.

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Different types of Plywood and their uses

I go through 6 different types of plywood and their common uses. They range from framing materials to cabinetry. If you have ever wondered what type of plywood to use for your project this video will explain it all!

MDF VS. PLYWOOD (Which Is Better?? Pros + Cons!!)

MDF or PLYWOOD? Which material is better? What are the Pros and Cons of both? Most DIYers want to know these things. In this video, The Honest Carpenter breaks down the similarities and differences between MDF and Plywood!

Both MDF and plywood are used in a variety of projects–but they mostly are used to build shelving, built-ins and cabinets. They can also be used in paneling projects.

They are both made of wood byproducts and glue. But, Plywood is made of actual wood layers, or “veneers”; each layer runs 90 degrees to the layers above and below it. MDF is made from fine wood pulp and glue–it’s kind of like cake batter that gets pressed into a sheet.

COST: MDF is generally a bit cheaper than plywood, about $35 per sheet. But, plywood comes in a huge variety of grades and types, with prices all over the place. Sandeply and radiata pine plywood tend to be reasonably priced, under $40. But cabinet-grade plywoods, like birch, maple and oak, can be up to $65 per sheet.

STRENGTH: Plywood is much stronger than MDF because of the cross-laid grain layers.

DURABILITY: Plywood is also more durable than MDF for this same reason. The corners hold up better–they don’t get dinged or bent as badly.

WORKABILITY: They both respond to tools in a similar fashion. MDF will produce sharper, cleaner cuts than plywood, which tends to tear out. Both can be drilled with drill bits. But, plywood holds a screw much better, especially in the edge. MDF edges should basically never been fastened into without extra support.

DUST CONTROL: Plywood makes dust similar to other lumber. But, MDF makes terrible dust! It’s like a powder. Be sure to wear a respirator and hook up vacuum filtration for your cuts.

INTERIOR / EXTERIOR: Plywood comes in both grades. But MDF is really an interior material. The wood pulp fibers make it soak up water like a sponge. It will bloat and rot quickly.

On the whole, I like plywood a lot more. But, MDF is a decent cheap alternative, and it also is very FLAT, which is one of its main advantages over plywood.

Which Plywood Should I Use? | DIY Basics

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