There are two things that are true about rough lumber. First, it’s entirely unsuitable as is for woodworking projects. Second, it’s a whole lot cheaper than regular lumber. Getting around the unsuitability and reaping the benefits of its relative cost is where the jointer and the planer come in. Both tools seek to help you transform wood that you got for a very affordable price into something suited for your DIY projects.
While they both do the same basic job and function very similarly, it’s important to remember that they have very different jobs.
The jointer is used to even out the flat edges of a board. They work by chewing off the bottoms of uneven boards. You remove a little wood with each pass and after a bit of work what came into your workshop as a slightly bent, dirty piece of wood is ready for your project that will turn in to the envy of the neighborhood.
A jointer consists of an infeed table, the blade, and an outfeed table. Place the lumber you are trimming up on the infeed table, run it through the blade and onto the outfeed table. Keep doing it until the face of the board is good and equal.
The fact that the jointer requires pressure from above to cut from below is worth keeping in mind when it comes to safe operations. Because you need to apply pressure to the top of the board to properly clean it up, you will push down and towards rotating blades.
Jointers tend to cost a nice chunk of change, especially relative to a planer.
Where the jointer flattens the wide, flat face of uneven lumber to a uniform depth, a planer gets it to the right thickness by shaving down the thin, tall edges. If you have both tools in your workshop, you are capable of doing everything needed to properly mill wood.
Planers have a different operation than do jointers in that you stand the board up on its side and run it through. The whirling blade is set on the top of the run, so the cut is from above. Run the wood down across the whirling blade.
That makes it a bit safer than a bottom-up cut of a jointer. Because you’re cutting for thickness instead of height, the planer cuts along a thinner section of wood.
One negative consequence of this is that planers tend to produce sniping, differences in the cut based on how firmly the wood is kept in one place. Most planers these days have features to help reduce sniping. Home DIY enthusiasts will want to find out about what techniques the pros use.
Between the two, planers are in general less expensive.
Buying rough lumber is a great way to stretch your hobby or DIY dollars, but you need to have a means on hand to convert it to something consistent and flat for use. You might already own a planer to help you get boards to a desired, consistent thickness. Those play a part here.
You’ll also want access to a jointer, which takes warped, curved pieces of rough wood and flattens then to a consistent depth using much the same action.
An easy way to tell the two apart is that the whirling drum of blades for a planer is on top. It’s safer, but you have to account for uneven gripping of the wood as the wood moves across the blade to reduce sniping. The whirling blades for a jointer are on the bottom and in the center of two tables. This eliminates the risk of sniping, but because you’re pushing down on the wood and towards the sharp moving parts, it has a higher risk of injury. Knowing this difference is not only critical to turning rough wood into usable lumber, but also staying safe in the workshop.
You could also consider what’s called a jointer planer combo, which – as the name implies – is a machine that has both functions.
Hi there! My name is Adam and I write for HealthyHandyman. I have a great passion for writing about everything related to tools, home improvement, and DIY. In my spare time, I'm either fishing, playing the guitar, or spending quality time with my beloved wife. You'll also often find me in my workshop working on some new project!