For new woodworkers, one of the of the most confusing things to learn is not what tools to use or how to use them, but how decide what kind of wood to use. There are a lot of choices and enough industry jargon to confuse anyone. I’ll try to boil it down to the basics you need to know to get started.
WOOD: THE BASICS
I am going to limit my discussion to the most common materials you will use for woodworking: Hardwoods, softwoods, plywood, and MDF. Of course this just scratches the surface but is enough to give you the confidence to head over to your local home center or lumberyard and make an informed buying decision.
Sometimes the term “lumber” refers to just solid wood. In other words, wood milled from a tree, as opposed to manufactured products and sheet goods, such as plywood or MDF.
There are two kinds of solid wood to choose from, softwoods and hardwoods. Technically, a hardwood is mostly wood that comes from a deciduous tree…one than has leaves, like oak or maple.
And they are usually physically harder than softwoods. An amusing exception would be Basla, an incredibly soft wood but since the Balsa tree is deciduous, it’s a hardwood.
Softwood is lumber that comes from a conifer tree, typically with needles and cones. Like a pine tree.
But usually when most of us talk about hardwoods we are referring to its physical hardness. When I talk about softwoods, I am generally talking about pine, which is a relatively SOFT wood.
Expansion & Contraction
All solid lumber is susceptible to expansion and contraction. During rainy or humid months, boards will draw in moisture, causing them to expand along their widths. Then in drier months they will contract as they lose that moisture. Expansion and contraction is an important topic to understand and keep in mind when building with solid wood but beyond the scope of this article. For small projects, this wood movement is not much of a problem, but if you are going to be making a big project such as a table top, I suggest Googling more about this topic.
When you go to a home center or lumberyard, chances are that scent you smell is pine. It’s the most common wood you can buy and usually the most affordable.
Pine boards are commonly used in home construction and framing. If you buy a 2×4, it’s most likely pine, such as Douglas Fir.
Home centers will carry large section of relatively inexpensive ¾” pine boards in various widths and lengths. They are perfect for projects that you intend to paint, but a lot of people love the natural look of pine too. If you like the look of pine, my suggestion is to show off what makes it unique and pick out boards with weird grain patterns and knots…the ones most people leave behind.
Pine is easy to work with. It cuts and sands smoothly and is gentle on your blades.
The main drawback to pine are that it is soft and will scratch and dent easier than hardwoods, so it’s not always the best choice for furniture that will receive a lot of use. It can also be challenging to find boards that are straight and not curved or warped, especially the wider they get.
Check to see if a board is straight by looking down its length with one eye. Just take your time to pick through the bin for the best boards you can find.
When you think of fine furniture and classic woodworking, you probably imagine wood species such as mahogany, or walnut or cherry. These represent just a tiny fraction of the hundreds or hardwoods and exotics you can buy.
Mostly, people buy hardwoods and exotic species because of their grain pattern, color, and durability. If you want to build something to last for hundreds of years, any hardwood is a good choice.
Hardwood is rarely stained and it would be a waste of money to cover it up with paint. It is almost always protected with a clear topcoat such as varnish, lacquer, or oil.
Hardwoods are great for combining to achieve different looks by using contrasting wood. Walnut and maple, for example are commonly seen in chess boards.
The density of hardwoods can make them tough on tools and they can be difficult to work with. Less-than-sharp table saw blades are notorious for leaving burn marks on cherry and maple, requiring a lot of sanding.
The biggest drawback is that hardwoods can be extremely expensive. Especially the more exotic species which can cost hundreds of dollars for a small board. Plus, it might be difficult to even find hardwood lumber where you live. Luckily, there are online hardwood retailers that will pick out good looking boards to ship to you.
However, the most common hardwood and relatively affordable species in America is oak. It, along with maple and walnut are usually available at my local Home Depot. Oak has its own issues, but it looks nice and is a great choice for starting out making things with hardwoods.
Plywood is one of the most popular and most versatile building materials you can use. It can also be the most confusing to buy. Mostly because there are so many types and grades, all with their own coded designations that describe its quality. Do a Google search for Plywood Grades to learn more on this topic.
Plywood differs from solid lumber because it is manufactured. Thin veneers of real wood are stacked in opposite grain directions and glued together. This crisscrossing is what gives plywood its strength and stability.
The thicknesses of plywood gets mind boggling with odd variations, but the most common thickness used in furniture and other woodworking projects is ¾” (18mm)…or at least close to that.
What to look for. In general, the more layers, the higher the quality. Plywood that comes sanded on both sides is best, and look for plywood with the least amount of voids along the edge.
For woodworking projects, Baltic Birch is commonly used. If your home center doesn’t carry it in full sheets, they usually sell it in cut sheets called “Handi-Panels” or “Hobby Boards”.
I really like using these for projects and recommend them. You can also buy specialty maple, oak, cherry or other hardwood plywood. These can be pretty expensive.
For shop projects, jigs or fixtures, there’s nothing wrong with saving money by buying a lesser grade of plywood. Mostly it’s an aesthetic difference.
Why use plywood? There are a lot of advantages to using plywood instead of solid lumber. In the U.S. at least, it’s fairly inexpensive. Plywood is very strong and stable: you don’t have to worry about expansion and contraction. It won’t warp. It’s a great option for large surfaces, such as a tabletop. It’s equally strong in each direction, so you don’t need to worry about grain direction, beyond what looks best.
Drawbacks to plywood
There are a few disadvantages to using plywood. For one, a 4’ x 8’ sheet of plywood is heavy and difficult to move around and manage alone. However, most home centers are able to cut it down into smaller pieces for you.
Second, while the face of plywood looks great, the edges can be an eyesore. You can cover these up with iron-on edge banding, which works really well, or make your own edge banding out of solid wood. If you are feeling really frisky though, just embrace the layered look and use it as a design element!
Lastly, the thin wood veneer on plywood can be tricky to cut. Cutting against the grain can cause it to chip out or splinter. A good trick is to run some masking tape along your cut line when cutting against the grain. And use a sharp blade.
Finally, I want to talk briefly about Medium Density Fiberboard or MDF. MDF is a completely manufactured product made by compressing wood fibers into boards.
It’s not to everyone’s taste, but it is inexpensive and can be very useful on some projects. MDF is commonly used in knockdown furniture, like what you might have to assemble from Ikea or other retailers. It’s usually covered with a laminate or veneer.
The material itself is super easy to machine and work with. It cuts like butter and edge profiles rout very easily. It’s a great option for small or decorative interior projects that you will paint. You don’t have to worry about it splintering the way wood or plywood can.
Drawbacks to MDF
MDF can be a bit fragile, especially near the edges where it can collapse like cardboard if you aren’t careful. The faces are very strong. If you use it for shelves longer than 2 feet or so, they will eventually sag. It’s also extremely heavy: a full size sheet is not fun to move around yourself.
But the biggest drawback to MDF is the nasty fine dust it creates when you saw of sand it. It’s definitely not something you want to breath: make sure you wear a respirator and have some sort of dust collector attached to your tools. The way my shop is equipped, I would not work with it every day, but a few times a year doesn’t bother me.
There are tons of other materials available, but this should be enough to give you the confidence to go to the home center or lumberyard and find exactly what you need for your project. The variety of exotic hardwoods are almost limitless and can be a lot of fun to experiment with, especially on boxes and other small projects that won’t break your bank.
But I would also like to encourage you to use free wood. Craigslist is a great resource for people giving away free lumber. Also, if you don’t mind a little extra work, consider using the wood from old pallets. I’ve broken down a lot of free pallets that were made out of oak. Most of all, have fun and don’t be afraid to try out something new!