sharing a joint

[estimated reading time 15 minutes]

the first step to good results in furniture construction (after acquiring the wood, of course) is jointing your boards. it’s so fundamental, it was common for traditional shops to allow apprentices to do any task (and potentially make mistakes) except the seemingly-most-basic and most-labor-intensive, rough-milling the stock. while this may seem counterintuitive, an error made in jointing can have disastrous results and mean your furniture project is fit for nothing but the burn pile before you even cut your first joint or drill a single hole.

let’s get a little terminology out of the way at the beginning. a “rough board” is a piece of a tree. think of a 50mm x 100mm x 2.4m board from the lumber yard. this is a fairly standard size (in countries still stuck in imperial measurements, this is roughly equivalent to an 8’ 2×4, though a little thicker in practice — you can also think of it as 4” 8/4×8’ — if these measurements have you wondering why anyone still uses imperial measurements, you’re not alone and i’m totally with you but i’ve included them for clarity — my shop has been completely metric since … well, since i was a child — japan has been a metric country since before i was born — in fact, it’s been the only valid measurement system for exactly a hundred years this year so it was before my parents were born, too). there are various terms for partially-jointed boards if you buy them that way but that’s unimportant. don’t buy presurfaced boards. remember that part about the masters not letting their apprentices do their jointing? how much do you trust that part-time kid working saturdays at the lumberyard running the skip-planer while exploring the deeper meaning of joints? yeah. about that much. trust premilled lumber to be somewhere between a potato-chip and a banana. it’ll make plywood look flat. plus, it’s relatively easy to do it yourself if you have a few simple tools — and none of those tools has to be a jointer. in fact, i generally hate using jointers and i don’t have one of my own. there are easier and safer ways and they’re often more efficient if you have a lot of wood to surface.

a “jointed board” is one with four surfaced sides and two rough ends. when we talk about surfaced, we don’t mean it’s ready for finish. we mean it’s flat and two opposite sides or edges (or ends, for that matter, though at this stage that’s not relevant) are parallel and the other pair are perpendicular. that might be a little hard to picture at first but it will come to you. think of a basic box. the top front and back must be parallel to each other. the right and left sides must also be parallel. the front and back must be perpendicular with (form right angles from) the right and left sides. the top and bottom represent the length of the board and those can still be incomplete at this stage but they’ll eventually be the fifth and sixths sides of our board.

so the question becomes how to get the board to that state. there are many ways and we’re going to look at a few, both with handtools (if you’re big on time, short on money and happen to be obsessed with traditional methods) and powertools. there’s a way to do it using a combination and we’ll look at that, too, though i don’t expect you’ll use it except in a situation where one of your machines dies. either you’re a handtool woodworker or you’re a hybrid woodworker and scrub planes and rough jacks really don’t feature much in the daily life of the second.

but before the wood gets jointed, it has to get from tree to shop. and that’s important. what makes a tree ready for use? in other words, when is it a tree and when is it a board? well, that’s two things — it has to be dimensioned and it has to be dry. when a tree is cut down, it’s full of moisture. really full. you can see the water streaming from the tree and if you try to work with the wood at that point you’ll actually get your tools wet. there are lots of woodworkers who specialize in “green” or wet lumber and they’re used to this aquatic environment. most, however, want to work with stable, dry wood. before it’s dried, though, to make that process far faster and easier, wood is usually dimensioned. a thickness, width and length are selected and boards are cut from the tree. remember, most of this is only coming from the part between the ground and the first branches so if you’re getting meters of wood from it, that tree is likely old, tall and massive. this isn’t an easy process in physical terms but it’s fairly simple in theory. most lumber coming from trees comes in standard dimensional sizes and ends up in a fixed thickness and width. if you get your wood from a small mill or an independent sawyer, this might not be the case. but from a lumberyard, you’ll usually see wood measured in 25mm increments of thickness, 50mm increments in width and .6m lengths (this works out to roughly 1”, 2” and 2’ increments for imperial-measurement people). so standard boards are often 50mm x 100mm x 2.4m or 200mm x 200mm x 1.2m, etc. we’ll use the first as our example because it’s probably the most common board you’ll find at any large store selling lumber and it’s a reasonable size to practice with — when you actually build full-size furniture, you’ll probably want something more like a 50mm x 250mm or 50mm x 300mm starting size to avoid having so many glue joints to make panels. but the process is the same.

drying is a matter of time or effort. you can just let the board sit in a relatively-dry location with good airflow and it will dry on its own. the wood will move as it dries and that’s something i’ve talked about in detail elsewhere and can talk about again if people are interested. but just assume it will move and no longer be even as flat as it was when it was first dimensioned — and that, unless you’re very lucky, wasn’t anywhere near flat at all. if there isn’t good airflow or the place isn’t dry, you’ll end up with moisture trapped in the wood and it will rot and get mold in it. this isn’t good. but you’re probably buying dry lumber so you don’t have to worry too much about this. someone else has already solved that problem for you. you can speed up the process by putting the wood in a kiln — if it’s a pressurized or “vacuum” kiln, the multi-year drying process can be reduced to days or even hours. but this is a lot of effort and energy compared to waiting for it to dry in a pile in a warehouse. most lumber you buy will have been dried in a standard desiccant-heat kiln rather than a pressurized one. the result is much the same. you can get what’s called “rebound moisturization” in the wood if it was dried beyond the ambient temperature and this can make dried wood a little difficult to bend but for all other purposes it’s realistically the same — and you can bend dried wood as long as you know it’s been dried and take a few extra precautions.

now that the wood has been dimensioned and dried (properly — because if it hasn’t, you’re screwed before you begin), you need to joint two faces and two edges. it’s usually best to start with a face because that’s a huge reference surface. let’s begin with how to do this with only handtools. what will you need? either three planes or three different plane setups on a single plane, a pair of winding sticks and possibly a long straight-edge (if you’re using a plane that’s too short for your boards). the other thing you’ll need is a square. a square that’s actually square. check it. i’ve talked a lot about how to check squares in the past. if you don’t know how, search my articles for how to check a square and you’ll get a lengthy description. i won’t go into that here. i assume your square is square.

which three planes? a fore, a jointer and a jack — in stanley’s numbering system this would be a six, a seven and a five. if you only have one plane, it’s probably a five and you can use it for all three purposes but it does the third better than the other two so if you’re going handtool-only, get yourself a couple of other planes and simplify your life. nobody wants to keep swapping out blades.

a foreplane (also called a tryplane) is a rough tool. it has a large mouth, a heavily-cambered iron and an aggressive, deep cut-depth. a jointer is much finer — a thinner shaving, a straight iron and a fairly-tight mouth. a jack is the basic plane and it has a flat iron, fairly small cut and relatively tight mouth. the jack is the optional step because you can always do that part later. once you’re finished with the jointer, the board is reasonably-ready for use.

start by securing your board to your bench. don’t have a bench? build a bench. this is easier with a bench. building furniture without a workbench is like trying to play football in the living-room. doable but messy and you’re going to break shit — quite possibly yourself — in the attempt. i secure things between the end/tail-vise and either a dog or a stop braced against two dogs. this is the setup i recommend for this (and pretty-much all woodworking) procedures. how you align the board is important. use wooden wedges or “shims” to make it so the board is sitting without rocking back and forth on the bench so the surface you are aiming to create is parallel with the benchtop. you can definitely do it without that but why you’d put yourself through that complexity and extra difficulty i have no idea.

once it’s secure, get your winding sticks out and put one on each end of the board. move them back and forth and mark the areas of the board that are high with a pencil. take your foreplane and lower those areas. anything that’s high, make slightly lower. then check again with the winding sticks. if you’ve never seen someone use them, you put one far away and one close to you, lower your body so you are looking just over the top of the near stick and see if the right and left edges of the far one disappear below the horizon at the same time. if they don’t, the one that disappears first is on the lower edge of the board and the one remaining above the horizon is high. mark the high part and apply your foreplane to it until regardless of where you put your winding sticks (start with them spaced almost end to end but move them back and forth to check to make sure every 20cm segment (approximately) is true and level.

when you are using your foreplane, don’t go end-to-end on the board. “traverse” the board — go across the grain, side-to-side. this will make the process much faster and easier and avoid some rather annoying problems. plus, the high and low areas will be concentrated in small sections. they won’t span the entire length of the board in most cases. just hit the parts that are high. hitting low parts will just remove usable wood and make the process take longer.

once the board appears flat to the winding sticks, you’re finished with the foreplane. get out your jointer (this is where the procedure gets its name) — what you just did was actually called “foring” or, later, “fairing” but these are arcane words and you’ll sound like an idiot if you use them in regular speech in the modern world.

with your jointer properly setup (lateral adjustment is key or you could just chase your tail for hours here), you will now be able to ride from ridge to ridge on the board, cleaning up any high spots left behind by the very aggressive cut and camber of the fore. this shouldn’t take very long. as you run end-to-end with the jointer, it will skip across from mountain to mountain and leave the valleys untouched. when you begin, you’ll hear a clicking pattern as it cuts, stops, cuts again, etc. when you start to get full-length shavings, the board is flat. you don’t have to keep going. you’re not aiming for a glass-smooth surface with your jointer. you’re aiming for flat. stop here.

the next thing to do is stand the board up on one edge. you’re going to joint the edge to be perpendicular to the face you just flattened. make sure you’ve taken note of which one you’ve flattened. this is important. i write “flat” on it. like the word. arcane symbols and such? yeah. people were illiterate back then and made up all kinds of things and people think they’re being very traditional but there’s no substitute for just writing on a piece of wood what it is. i often write “reference flat” on the first one then “second flat” on the other side so i can tell the difference. some people think i’m being anal about it. get them confused once and waste two hours and you’ll start thinking the five seconds with a pencil is a better approach, too.

you can do this in your end-vise or, again, between the vise and a dog on your benchtop. i’ve used both methods and i prefer anything longer than about a meter to be done on the benchtop because it’s fully-supported. you can do this on the floor if you want or anywhere else convenient. but i like benchtops so i’ll assume that’s where you’ll do it, too. take your square and hold it against the reference face, running it along the length of the board. mark with a pencil where there are high areas. if they’re really high, use your foreplane to knock them down. if they’re not very high, skip straight to the jointer. start by just attacking the areas that are high and making them flat, inline with the rest of the edge. once it’s approximately flat (keep checking with your square along the entire length — you can easily go too far, overcompensating for something and pushing it out of square in the other direction), start taking full-length shavings. when you can get a clean, even-thickness shaving the entire length of the board, you’re flat. write on that edge that it’s the flat, reference edge. this is important. you’ll forget. i do. it’ll bite you in the ass if you do. ass-biting is bad.

at this point, you can use a marking-gauge to mark a line denoting the desired width of the board but i think marking-gauges are a bit overrated. use one if you like (or a panel-gauge, which is a bit more useful in some cases) but you have a combination square with an adjustable bar. you can just set this to the desired width, take your pencil and run the whole thing along the length of the board to make a mark. if there’s a lot to remove, you can saw close to the line you just drew. if there’s not that much to remove (or if you really like planing), flip that board over and go to town with your foreplane. when you get close to the line, do the same procedure to make sure it’s flat and perpendicular — to the reference face. don’t forget which is the reference face. when it’s done, write on it that it’s flat and the second edge. again, no ass-biting necessary.

the same procedure can now be done for the second face. use your combination-square (or a marking gauge if you’re old-school) and draw around all four edges/ends of the board (making sure you’re measuring from the reference face — see how this could all go very wrong at this point?) then secure the board with this face up just like you did in the first step and repeat it until this face is flat and perpendicular to your reference edge. check often with the winding sticks and combination-square. checking takes a few seconds. overshooting your mark or going in the wrong direction can cost you hours or a ruined board. it’s worth checking more than you think you need. when it’s done, mark this face as secondary and flat. procedure complete.

congratulations. you’ve just done the most commonly-assigned task for apprentices to prove their abilities and progress to the next lesson. learning to joint a board from rough to four-square is fundamental to woodworking and it’s not a trivial exercise. if you’ve done it well, you can be extremely proud of yourself. i know i was the first time. and every time. it never becomes mindless. you always have to pay attention. if it felt difficult, that’s because it is. it’s a real skill.

what did you need the jack plane for, you’re wondering? you can use that as a lighter alternative to the jointer for some wood-removal tasks but really it’s a good way to precisely take off a little wood. it’s the next step that it’s particularly good for. not just making the two faces flat and parallel but making them the thickness you’re aiming for. once they’re parallel, they may still be too thick. there’s no reason to use a heavy number-seven to knock it back from 30mm to 20mm. just use a jack and you’ll be far less exhausted. you can, however, use the jointer for this task. or you can do it with the fore before you start jointing. procedure varies and it’s totally up to you.

this procedure, however, is traditional and extremely slow compared to the machine version used in most shops today. using machines doesn’t make it less technical. but it does make it far less effort and physical work. and you can get a board ready in minutes rather than what often works out to be hours if it’s not already close to flat.

the procedure in most shops is surface one face and one side at the jointer, run it through the planer to get to desired thickness referencing on the bed of the planer and the jointed face then ripping a parallel edge on the other side at the tablesaw. this procedure works and is relatively fast. if you need an explanation of how to use a jointer, i’m happy to provide one but i suspect if you own one you already know how to use it. if you don’t own one, you may be looking for another procedure and that’s what we’re talking about today.

you don’t have to have a jointer to joint a board. and you don’t have to go to all the effort of using handplanes if you want to use a machine to do it. i assume you have a thickness-planer, whether it’s a hardcore one or just a cheap benchtop lunchbox model — the dewalt one you see in so many shops is ideal for the task and, while it sounds like a screaming devil on halloween, it gets the job done and your ears will (hopefully) recover quickly.

the key to jointing the face of a board without a jointer is using a sled. you want the sled to be at least as long as the board you’re jointing. it doesn’t have to be truly flat but flat helps with stability so aim for flat. if it’s made of plywood, you’re probably doing ok. mdf is good, too, though mdf is heavy and dusty and i simply refuse to work with it anymore. but a solid sheet of 19mm plywood is ideal for the task. there are many ways to secure the board to the sled. some people use hot-glue. others use screws (please, if you use screws, make sure you counterbore the holes so when you plane the wood you don’t even come close to planing the tops of the screws or you’re going to wreck your planer and potentially start fires and cause yourself some serious harm — don’t do this). i use wedges (no, not the thing bullies did to nerds in elementary school) — on the leading and trailing edge of the sled, i have fences screwed from the bottom (with very short screws so they don’t come anywhere near the top of the fences, nevermind the top of the actual board i’m jointing) about 20mm tall. i use a mallet to tap in opposing wedges whatever sizes i need to firmly secure the board to the sled. this is sufficient. you can use double-stick tape to add to the hold of the board on the sled. use shims to stabilize the board so it doesn’t rock side-to-side. run the sled-and-attached-board through the planer until the top is flat then (and this is unnecessary but nice) run it through with a very thin pass to make sure you haven’t made a mistake and it really isn’t just an illusion. mark this face as the reference one. i know this seems silly and overkill. but it’s not.

now take that board to your tablesaw. you’ll need another sled. some people call this a jointing sled or a tapering sled. they’re really just all the same thing. it’s a piece of plywood with a few holddown clamps screwed to it so you can hang the board you’er working on just over its straight-edge. as the sled runs in the track of your tablesaw, it will trim any piece of your board that overhangs that edge straight. make sure you put the board on the sled with the reference face down against the sled. this will ensure (as long as your tablesaw blade is accurately set to 90) the new reference edge will be perpendicular to the reference face. mark your new edge. don’t skip this step. you’ll forget.

remove the board from the sled and run it through the tablesaw again with the reference face against the bed of the saw to get the board to width and mark that edge. take the board to your planer and run it through with the reference face against the bed of the planer to get the board to thickness. again, mark this face accurately. your board is now flat. this whole procedure should take only a few minutes and it doesn’t involve complex jointer setup or any dangerous spinning cutter heads. it works with boards of any thickness up to the maximum cut depth of your tablesaw (minus the thickness of the plywood for your sled, which can be as thin as 9mm and still work perfectly well). the maximum width of the board is determined by your planer — even a cheap benchtop planer will usually do at least 33cm and that’s a pretty wide board. getting a jointer that will handle a 33cm board is … worse than cost-prohibitive. if you can find a 300mm-wide jointer for less than five or six grand, consider yourself lucky. a 330mm planer, though, you can often pick up used for a hundred bucks or new for a few hundred. add a single sheet of plywood, a few fences/cleats and some scrapwood wedges and you’ve got yourself a 330mm jointer and your fingers are safe to joint another day.

just in case you’re curious, you can do the tablesaw stuff on a bandsaw, a tracksaw or even a circular-saw with an edge guide. these methods all work but there’s one common painful flaw to them all — they’re all cumbersome and require a lot more setup. bandsaw tables are realistically tiny compared to tablesaws, even huge bandsaws — and if you have a huge bandsaw, you’ve probably got a tablesaw, too. this is what tablesaws are built to do so, unlike some other procedures i can imagine, this is exactly what you should be using it for. tracksaws are great but they’ll take time and effort to make do this task they weren’t really built for and a circular-saw with an edge guide is something you really only want to use if you have no other option.

what’s the hybrid approach? skip the planer-sled and flatten one face with the foreplane and jointer method we’ve already discussed. then do the rest the machine way. you can save yourself the construction of the sled but it’ll cost you a lot of hard work and you’ve got the machines already. not sure why anyone would bother but i’ve seen this method used a lot. i figure either go with the powertools or go with the handtools. if you like scrubbing at a board with a plane for hours, more power to you. but i would rather do my handtool work on complex joinery and finish planing. to each their own, though.

anyway, that’s how to joint a board. there are certainly other ways to do it. but i think these are the most effective and they’re used by many serious professionals every day. there are simpler methods — you can skip the sled and plane the board flipping between passes and you’ll get approximately flat that way, for example. but they have disadvantages (in this case you usually end up losing a lot more thickness in the final board and you can end up with some really awful planer-snipe, to the point of actually damaging your planer if your board is really warped). but i suggest these because they work in all cases with all boards as long as they fit (in the case of the machines) or you can handle them without running out of energy (wow it’s a lot of energy to flatten a bunch of boards before you even start cutting the joinery for a dining-table).

whichever method you choose, enjoy the peace of knowing you can take something that used to be a tree and make something useful from it. if all you do today is flatten a single board, that’s a huge accomplishment that took humans thousands of years to perfect and achieve. every time you do it, take a moment to remember you’ve followed in the footsteps of thousands of generations of craftspeople and smile. i don’t mean get silly about it and post pictures on instagram every time you flatten a board. but the first time you get out the planes and the result is awesome? do that shit up and have a party. thanks for reading. see you on the ‘gram, newly-surfaced one.

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