Hand building and wheel
Lidded Boxes and Treasure Boxes
On a jar, you measure the lid. On a box, you cut it. Build the form closed, with no opening at all, then slice the lid off the top of it. The two halves fit because thirty seconds ago they were the same piece of clay, and that one difference makes a box far easier than the lid you have been putting off.
Jump to a section
The short version
A box is a sealed brick that you cut in half
The one question
Do you want the lid to look like it grew out of the box, or to look like a lid? Grew out of it means you build the box closed and cut the lid off. Looks like a lid means you build the box open and make the lid separately. This version teaches the first one, because it is the one that cannot be measured wrong.
Roll two slabs at three eighths of an inch, rib both faces of each one, and then wait. That wait is the technique. A slab that still droops when you lift it by one corner will build you a box with bowed walls and a lid that never sits flat.
Once they are firm, cut a base, four walls and a top from paper templates. Score and slip every face that touches another face, build the walls onto the base, press a coil into all eight inside seams, then cap it. You now have a sealed brick with air trapped inside it, and that trapped air is holding the walls apart while you work.
Wait again. Then draw your cut line all the way round with a ruler, check it meets itself at the fourth corner, and cut through one wall at a time with a thin blade held at a steady angle. Scratch a single mark across the join so you know which way the lid goes back on, because it only fits one way. Score a strip of clay around the inside of the rim standing about a quarter inch proud, and that is the lip your lid drops onto.
After that, the two halves only have one job left: live the same life. Dry closed, bisque closed, and wax both faces that touch before the glaze firing, or they come out of the kiln as one object.
01 · The one idea
You do not measure a box lid. You cut one.
Why that matters more than it sounds
Every hard thing about lids is a measuring problem. Take the number off one object, hold it in a tool, reproduce it in another object twenty minutes later, in wet clay, from memory. Cutting deletes that entire job. It does not make it easier. It removes it.
A jar and its lid are two separate objects that have to agree. The only thing making them agree is a caliper and a careful hand, and that is a genuine skill worth learning. We have a whole page about throwing lids that fit, and none of it applies here.
A box works the other way round. You build it closed, with no opening at all, and then you cut the lid off it. There is no measurement to take, no number to transfer, and nothing to get wrong at the moment you are most likely to get something wrong. The lid matches the box because it is the box. Every wobble in your wall, every thumb print, every slightly-out corner is matched exactly on the other side of the cut, and a fit that comes from cutting is tighter than a fit most people can measure.
It also means the surface runs straight through. A stamp, a carved line or a run of glaze that crosses the join lines up on both halves, because it was one surface when you put it there. That is the look people are actually after when they say they want a nice box, and it is almost impossible to fake with a lid made separately.
What you get in exchange is one new job, and it is a much smaller one. Keep the cut clean, and keep the two halves living the same life afterward. They are now two things pretending to still be one, and every box failure after the cut comes from letting them forget it.
02 · Why this page reads like this
A camera cannot show you a wait
What the video does better
Hands. How hard a rib presses, how a blade actually enters a wall, how somebody supports a lid at the second it comes free. Nobody has ever written a sentence that teaches those, and we are not going to try.
There are hundreds of box tutorials on YouTube and we have linked eight of the best ones further down this page. So it is fair to ask why anybody would read about it as well.
Because the two are good at different things, and a box is the clearest case of it we know of. A box is mostly waiting. Roll the slabs, wait. Build it, wait. Cut it, wait. Those waits are not dead time between the real steps, they are the technique, because almost every box that fails was worked at the wrong stiffness rather than in the wrong order.
And waiting is the one thing a camera cannot show you. Two hours of a slab firming up is a jump cut. You watch somebody pick up a slab that is already exactly right, you come away certain you understood the whole thing, and then you try it with clay straight off the roller and cannot work out why your walls will not stand up. What you retained was a feeling. What you needed was an order of operations with the waits marked in it.
There is a second thing text is better at, and it is duller: a page sits still. A video plays at its own speed and you cannot pause it with clay on your thumb. A list waits exactly where you left it and comes back the second you look down.
So read this once. Watch one or two of the videos, because your hands need to see hands. Then leave the checklist near the end open on your phone while you work, because reading a step ten seconds before you do it is what turns watching something into remembering it.
03 · The anatomy
Two ways to make a box, and the six parts they are built from
Both drawings are cut straight through the middle, with the lid lifted off so you can see what it lands on. The one on the left was built closed and cut. The one on the right was built open, with the lid made separately.
- The cut line. Where the blade went round. On a finished box it is a hairline, and everything above it lifts off. There is no seat here at all until you build one.
- The inner lip. A strip of clay scored around the inside of the box rim after the cut, standing about a quarter inch proud. It is the only thing stopping the lid sliding sideways, and it is the step people forget.
- The registration mark. One scratch straight across the join. A cut lid seats properly in exactly one position and nobody has ever remembered which one it was.
- The corner coil. A thin coil pressed into every inside seam and blended in. Invisible forever afterward, and the difference between a box that holds and a box that opens along a corner in the kiln.
- The collar. On a box built open, the outer part of the rim is left standing taller than the inner part. The lid sits down inside it and the collar keeps it there.
- The ledge, or gallery. The inner part of that same rim, set down by the thickness of your lid. This is the surface the separate lid actually rests on, and the surface you measure if you go this route.
Four kinds of box, and which one to make
| Kind | How the lid is made | What holds it in place | Best for |
|---|---|---|---|
| Cut lid | Built or thrown closed, then cut off in one pass | An inner lip added after the cut, or a cut bevelled inward the whole way round | Anything where you want carving, stamping or glaze to run straight across the join |
| Gallery lid | Made separately from the same slab, to fit inside the collar | The collar standing above the ledge | Boxes you open every day, and anything big enough that a long cut could wander |
| Overlapping lid | A shallow tray that drops over the outside of the whole box | The skirt gripping the outside of the walls | A first box, and anything you want to lift one handed without looking |
| Treasure chest | Built closed with a curved top, then cut straight round the sides | An inner lip, with the weight of the curve sitting down into it | Chests, keepsake boxes, anything getting a clasp or feet |
If you are choosing right now, cut one
Not because it is easier to build. Because it is the only version where the fit is decided by the clay rather than by you, so your first box comes out with a lid that actually sits down on it. Learn the cut on something small, then make a gallery box when you want one you can open a hundred times a week.
04 · The method
Building a cut lid box, in twelve steps
Building a cut lid box, in seven steps
This is the method for a rectangular box with a flat lid. A treasure chest is the same method with four extra moves, and those are further down.
What is on the table before you start
Paper templates
Cut them out of printer paper before you touch clay. A base, a top, two long walls and two short walls. Paper is where you find out your box is not square.
A thin blade
A fettling knife or a sharp needle tool. Thin matters more than sharp, because a thick blade wedges the wall apart as it goes through.
A metal rib
For compressing both faces of every slab. This is the step that decides whether your flat pieces stay flat, and it takes about ten seconds each.
A ruler and a square
For the cut line, and for checking corners at ninety degrees while you build. A box is the one form where your eye is not good enough.
Slip and a scoring tool
Eight seams need both. If you want the full method, the score and slip page is the one to read before this.
Loose plastic
Dry cleaners bags, not tight wrapping. You are slowing the drying down rather than stopping it, and everything on this page happens under it.
The steps, in the order they happen
Three of these are waits. Do not treat them as gaps between the real steps.
- Roll two slabs at three eighths of an inch. One for the base and the top, one for the walls. Three eighths sounds heavy and is not, because the wall you end up with after ribbing, drying and firing is nothing like the slab you started with. Thin slabs are where boxes are lost.
- Compress both faces of every slab with a rib. Both faces, not one. Compression is what stops a flat slab warping as it dries, and a box is almost entirely flat slabs, so this is the single highest paying ten seconds on the page.
- Wait for firm leather hard. A slab you can lift by one corner without it drooping. Under loose plastic that is somewhere between one and three hours here, depending on the day and the clay. This is the step people skip and it is the whole difference between a box and a puddle.
- Cut your pieces from the paper templates. Base, top, four walls. Cut the two long walls to the full outside length and the two short walls to fit between them, or bevel all four vertical edges at forty five degrees if you want a corner with no visible seam.
- Score and slip every face that will touch another face. Real scratches and real slip, on both sides of every join. An under scored join is the most common reason a box opens along a corner in the kiln, and there is no way to find out until it does.
- Stand the walls on the base and join them one at a time. Support the outside of each wall with your free hand while you press, and check the corner against a square before you move on to the next one.
- Press a thin coil into every inside seam. Eight of them, four vertical and four along the floor. Blend each one in with a wooden tool. You will never see these again once the lid is on, so this is your last chance at them.
- Cap it. Top slab straight across, joined exactly like the others. The box is now a sealed brick with air trapped inside, and that air is doing real structural work: it holds the walls apart and stops them bowing while you handle it.
- Wait again, to firm leather hard and no softer. Cutting a soft box drags the blade, pulls the walls inward and leaves you an edge you cannot clean.
- Draw the cut line all the way round with a ruler. Then check it meets itself at the fourth corner before you cut through anything. A line two millimeters out at the last corner is a lid that rocks for the rest of its life.
- Cut through one wall at a time, blade at a steady angle. Vertical gives you a flat seat. Tilted consistently inward gives you a lid that drops in and seats itself, and then you do not need a lip at all. Pick one and hold it the whole way round. Support the lid with your free hand as the fourth wall lets go.
- Mark the join, then add the inner lip. One scratch across a corner, through both halves. Then score a strip of clay around the inside of the box rim, standing about a quarter inch proud and set back from the wall by the thickness of your lid. Put the lid back on, check it drops in cleanly, and leave it on.
- Roll two slabs at three eighths of an inch and rib both faces of each one. Both faces. That is what stops them warping.
- Wait until you can lift a slab by one corner and it does not droop. One to three hours under loose plastic. Do not rush this one, it decides everything after it.
- Cut a base, a top and four walls from paper templates, then score and slip every face that touches another face, on both sides.
- Build it closed. Walls onto the base one at a time, a thin coil pressed into all eight inside seams, then the top straight across. It is a sealed brick now, and the trapped air is holding the walls apart.
- Wait again for firm leather hard, then draw the cut line all the way round with a ruler and check it meets itself at the fourth corner.
- Cut one wall at a time with a thin blade at a steady angle, supporting the lid as the last wall lets go. Scratch one mark across a corner so you know which way it goes back on.
- Score a strip of clay inside the rim, standing a quarter inch proud. That is the lip the lid drops onto. Put the lid on and leave it on.
Watch somebody take the lid off one
The cut is the moment everybody is nervous about, and it is far less dramatic than it looks in your head. This is the clearest close up of it we found: a hard slab box, a steady blade, and a lid that comes away in one piece.
Note how little he hurries, and how the box is supported from the inside as each wall releases.
05 · The other way
Building it open, and making the lid separately
Sometimes cutting is the wrong answer. A long box gives a blade a long way to wander, a very soft clay body does not take a clean cut at all, and a box you open twenty times a day is better off with a proper seat than with a hairline join. Here is the alternative, in six moves.
- Build the box open. Base, four walls, no top. Same slab thickness, same ribbing, same scoring, same coils in the inside seams.
- Decide on a gallery or a flange before you build, not after. A gallery is a ledge on the box. A flange is a ring underneath the lid that drops into the mouth. Both work. Both at once does not.
- For a gallery, score a strip around the inside of the rim, set down from the top edge by the thickness of your lid. The wall left standing above it is the collar, and the collar is the part that stops the lid sliding.
- Cut the lid from the same slab as the base, using the same template, then trim it back all the way round by the wall thickness so it drops inside the collar instead of sitting on top of it.
- Try it wet, try it stiffer, try it again. This is the tax you pay for not cutting. Two separate pieces have to be checked against each other at every stage, because they are shrinking on their own schedules.
- Dry them together, closed, on the same board. Exactly as you would a cut box. Nothing about that changes.
The trap in this method
A flange deep enough to hold is not the same as a flange deep enough to jam. Aim for about a quarter inch of drop. Deeper than that and the lid needs two hands and a wiggle every time, which is the opposite of why you made a box.
06 · On the wheel
A thrown box is the same trick with a better tool
Everything above is true on the wheel as well, and one part of it gets much easier. Throw a closed form, let it stiffen, then hold a needle tool against it while it turns and let the wheel cut the line for you. It is the straightest, most level cut available to anybody in any technique, and you did not have to draw it.
Getting to the sealed form is the part worth reading up on separately, because collaring a pot all the way shut has its own set of problems. Our page on throwing enclosed forms covers that half in full. What follows is only what changes once the pot is closed.
- Leave the wall thicker where the cut will go. You are about to remove clay with a needle and then clean both edges, and a thin wall there gives you nothing to work with.
- Let it stiffen on the bat before you cut. Soft leather hard. A wet closed form will collapse the moment the air pocket is opened.
- Cut at slow speed, needle held still. Move the tool in, hold it, and let the pot come round to it. Chasing the line by hand is what makes a wavy cut.
- Cut most of the way, then stop the wheel and finish by hand. The last section, cut with the wheel stopped, keeps the lid from dropping in and scarring the rim as it releases.
- Throw a lip or trim a seat. Either add a small ring inside the rim while it is back on the wheel, or trim a gallery into the standing edge. Both are quick with the pot already centered.
- Trim the lid sitting on the box, not against a number. The box is already a perfectly centered chuck for its own lid, which is the other reason this method is worth the trouble.
Where a box beats a jar
A thrown jar lid is a circle you have to reproduce from a measurement. A thrown box lid is a circle the wheel already cut. If you have been fighting jar lids, this is the friendliest thing on the wheel to try next.
07 · The chest
A treasure chest is a cut lid box with four extra moves
Nothing about the build changes. It is still slabs, still closed, still cut. The curve, the clasp, the feet and the hinge are all added on top of the method you already have, and one of the four will ruin the piece if you get it wrong.
- Build the curve before you cut, not after Cap the box with a flat top as usual, then build the barrel curve on top of that: a slab draped over a rolled newspaper log, left to stiffen into shape, then scored on at both ends. Cut the straight line round the four sides afterward and the whole curved top comes away as one piece. Trying to add a curve to a lid that is already off means fitting two separate curved things together, which is the exact problem you were avoiding.
- The clasp has to be cut through as well This is the one that ruins chests. Any strap, tab, hasp or lock that crosses the join will weld the chest permanently shut in the glaze firing, and there is no fixing it afterward. Add it before you cut and take the blade straight through it, or make it as two separate pieces that meet at the join and never actually touch.
- Four feet, scored on like anything else Feet lift the chest off the shelf, stop it rocking on a floor that is never quite flat, and give any glaze that moves somewhere to go that is not the kiln shelf. Keep them small and keep them at the corners. A chest with feet reads as furniture and a chest without them reads as a brick.
- The hinge is not made of clay A clay hinge that actually pivots does not survive a firing in one piece, and every attempt ends the same way. Build two short tubes on the back of the box and two on the lid, offset so they interlock, fire them like that, then thread a cord or a length of wire through afterward. The hinge arrives after the kiln, not before it.
- Build the curve before you cut. Drape a slab over a rolled newspaper log, let it stiffen, score it onto the flat top, then cut the straight line round the sides. The whole curve comes away as one piece.
- Cut through the clasp too. Any strap or hasp crossing the join welds the chest shut in the glaze firing. Add it before the cut and take the blade straight through it.
- Four small feet at the corners. They stop it rocking and keep any moving glaze off the kiln shelf.
- The hinge goes on after the kiln. Fire two interlocking tubes, then thread cord or wire through them. Clay hinges do not survive a firing.
Anything hollow needs a hole
A domed lid, a hollow knob and a hollow foot are all sealed pockets of air, and sealed air expands in a kiln until something gives. Put a pinhole somewhere it will not be noticed, on every hollow part, every time. The box itself is fine, because you cut it open.
The whole chest, start to finish
A slab treasure chest built the plain way, with the curved lid, the clasp and the feet all shown in order. It is filmed for a classroom, which is exactly why it is useful: nothing is assumed and nothing is skipped.
Watch how the curved top is supported while it stiffens. That support is the entire reason it holds its shape.
08 · Clay and thickness
Three eighths of an inch, and which bag to buy
Read the gauge in eighths
The big marks on a slab roller gauge are quarter inches and the small ones between them are eighths. Almost everybody reads them all as quarters the first time and lands nowhere near the thickness they wanted. The gap also includes the mats, so your final setting sits a little under the number on the dial.
Get certified first
We have two slab rollers, both open to every Level, and both will roll a slab up to thirty inches. You need the slab roller and slab molds certification before you touch either one. It is free, it takes about twenty five minutes, and it covers the parts that damage the machine.
Three eighths of an inch is the number for a box, and it is the same number we give for a slab mug. It sounds heavy written down and it does not read as heavy in the hand, because ribbing, drying and firing all take something off it.
Go thinner and two things happen. Flat panels warp on their way to leather hard, which is bad enough on a mug and fatal on a box, where four walls all have to stay square to each other. And you leave yourself nothing to cut into. The blade has to pass cleanly through a wall and you have to be able to clean both edges afterward without going through.
Go much thicker and the box stops being a box and starts being a paving slab with a hollow in it. It also dries slowly and unevenly, which is how corners crack.
No slab roller free, or not certified yet? A box needs about the same area as a sheet of paper and a half. You can roll that by hand with a rolling pin and two wooden guide sticks in about five minutes, and the result is genuinely just as good. Guide sticks are what make it even, so use them.
Which of our eight bodies to reach for. Any of them will make a box. These three make it easiest, and the numbers are each body’s published shrinkage from wet to fired.
Berlin Gray
About 12% shrink. A dark gray stoneware with a very fine grog through it, and that grog is exactly what keeps a flat slab behaving while it dries. Structurally the best behaved slab clay we stock, which makes it the best box clay we stock. Start here if you want the box to work.
52 Buff
10.0% shrink. The house starter and the least expensive bag in the building. Slightly coarse, forgiving, and it shrinks less than anything else we carry, which quietly makes it the friendliest clay here for a first box.
Speckled Buff
12.0% shrink. Warm and smooth, and it fires to the desert brown speckle a lot of members come here for. It handles slabs well and hides a seam better than a plain white body does, which matters on a box with eight of them.
The one to leave until later
#16 Porcelain shrinks 13.9%, the most of anything we carry, and it will find every joint you rushed. It makes a beautiful box and it is not the clay to learn the cut in. Make a few in something else first.
09 · When it goes wrong
Eight ways a box goes wrong, and what actually caused it
Four ways a box goes wrong tonight
- The walls bowed outward You built on slabs that were still soft. There is no fixing it once the box is closed, and no amount of care later gets a lid to sit flat on a bowed rim. Next one, wait for firm leather hard.
- A corner opened up while it dried Under scored joins, or two slabs joined at different wetness. Score harder than feels necessary, slip both faces, and build the whole box from slabs that came off the roller together.
- The blade dragged and pulled the wall inward Cut too soon. The box was still soft enough to move. Give it another hour under plastic and try again on the next one.
- The cut edge crumbled instead of slicing Cut too late. Past leather hard, a blade chips clay rather than parting it. You can usually still tidy the edge with a barely damp sponge, and you can never tidy it with a knife.
- The lid rocks The blade angle changed somewhere on the way round, so the two mating faces are not the same shape. It will seat in one position and rock in the other three. Hold one angle the whole way, and mark the join so you always put it back the way it was cut.
- The lid and the box warped in different directions They dried apart. Two halves that were one object have to stay one object all the way to the bisque: same board, same plastic, lid on.
- A big flat lid sagged in the middle Over about five inches across, a flat slab lid has no reason to stay flat. Give it a gentle curve, a rib of clay underneath, or a thicker slab. A chest solves this by accident, because a curve is a structure.
- It came out of the glaze firing as one object Glaze on the two faces that touch. Glaze is glass, and glass welds. Wax the lip and the underside of the lid, wipe both, and this never happens again.
- The walls bowed outward You built on soft slabs. Wait for firm leather hard, where a slab lifted by one corner does not droop.
- The blade dragged, or the edge crumbled Cut too soon, or cut too late. Firm leather hard is the window for both the building and the cutting.
- The lid and the box warped apart They dried separately. Same board, same plastic, lid on, all the way to the bisque.
- It came out of the kiln welded shut Glaze on the two faces that touch. Wax the lip and the underside of the lid, then wipe both.
10 · Drying, firing and glazing
The two halves have to keep living the same life
Everything from here is about not letting the box and its lid become two separate objects. They dry together, they fire together, and the only moment they are allowed to be apart is while you are putting glaze on them.
The rule under all of it
Whatever happens to one half happens to the other half, at the same time, in the same place. Every drying and firing failure on this page is a version of breaking that.
- Dry it closed and dry it slow. Lid on, under loose plastic, on a flat board rather than a wire rack. Flat panels want to curl, and a board holds the base honest while it firms up.
- Turn it over once, partway through. The face against the board dries slower than the rest. Flipping it once, when it is stiff enough to handle, evens that out and takes most of the warp out of the base.
- Take the lid off only to check, then put it back. It is tempting to leave it off so the inside dries. It does not need to, and the two halves stiffen at different rates the moment they are separated.
- Bisque it closed. Cone 05, and bisque firings here are free. Firing it assembled means both halves shrink into the same fit they had going in.
- Fix the fit at bisque, not later. If it has tightened up, sand the lip or the lid edge with wet sandpaper. Bisque sands easily and this is the last cheap moment to adjust anything. After the glaze firing you are grinding glass instead.
- Wax both faces that touch. The lip and the underside of the lid. Wax the dry piece first and rinse afterward, which is our order and the opposite of most tutorials. Then wipe both waxed faces with a barely damp sponge so no stray glaze bead is left to weld them.
- One dipping glaze per piece. That is a studio rule and it applies to the box and the lid as one piece, because they are one piece. The full method is on the dipping glazes page.
- Fire it closed. Both faces waxed and wiped, lid seated the way you marked it. The two halves shrink together and the fit you made is the fit you get back. If a chest has a heavy overhanging lid and you would rather not risk it, fire them apart and accept a slightly looser seat.
Glaze goes to cone 5½, which is cone 5 with a twelve minute hold, so somewhere between cone 5 and cone 6. Glaze firings are five cents per cubic inch with a $4.80 minimum, and the calculators page will price a piece before you make it. If the lid did fuse anyway, the fused and sharp pottery page covers getting it apart without losing the box.
11 · The videos
Four more boxes, four more potters
Four of the eight are already up the page, next to the method each one belongs to. These four are complete builds worth watching end to end, and none of them are us.
Keep this open at the table
The whole box, on one screen
Tap copy and it lands in your notes app, so you are not scrolling a page with clay on your thumb.
Before you cut
- Slabs at three eighths of an inch
- Rib both faces of every slab
- Wait: lift by a corner, no droop
- Cut from paper templates, not by eye
- Score and slip both sides of every join
- Coil into all eight inside seams
- Cap it. It is a sealed brick now
The cut
- Wait again. Firm leather hard, no softer
- Draw the line with a ruler, all the way round
- Check it meets itself at the fourth corner
- One wall at a time, thin blade
- Hold one blade angle the whole way
- Support the lid as the last wall lets go
After the cut
- Scratch a mark across the join
- Lip inside the rim, a quarter inch proud
- Clean both edges with a damp sponge
- Dry closed, flat board, lid on
- Bisque closed at cone 05
- Wax the lip and the lid underside
- One dipping glaze. Fire it closed
12 · Questions
The ones we get asked about boxes
Anything not here is on the studio FAQs page, or ask whoever is behind the counter.
Do I really not need calipers?
Not for a cut box, no. That is the whole reason this method exists. You need calipers when two objects have to agree, and a cut box is one object that you separated. If you build the box open and make the lid separately, then yes, measure it.
How long is the wait, really?
One to three hours under loose plastic for a three eighths slab, and it varies with the clay, the day and how much you handled it. Do not go by the clock, go by the test: lift the slab by one corner. If it holds its shape, it is ready. If it droops, it is not.
Can I make a box in one session?
Usually yes, if you roll your slabs at the very start and go do something else while they firm up. Plenty of people roll slabs, throw for two hours, then come back and build the box. Two sessions is easier and nothing is lost by splitting it: build it closed one day, cut it the next.
What if my lid does not fit after the bisque?
Sand it. Wet sandpaper on the lip or the lid edge, a little at a time, checking as you go. Bisque sands easily and this is the last cheap moment to fix a fit. Do not leave it until after the glaze firing, when you would be grinding glass instead of clay.
Can I glaze the inside of the box?
Everywhere except the two faces that touch. Inside walls, inside floor, underside of the lid away from the rim, all fine. The lip and the ring of the lid that lands on it get wax and nothing else, and both get wiped afterward.
Can I put a working hinge on a chest?
Not out of clay alone. Build two short tubes on the box and two on the lid so they interlock, fire them like that, and thread a cord or a length of wire through afterward. The moving part arrives after the kiln.
How big can a box be?
Bigger than you think, as long as the lid is supported. Over about five inches across, a flat lid wants a curve, a rib underneath or a thicker slab, or it will sag on its way to leather hard. Our slab rollers will roll up to thirty inches, so the machine is not your limit. Drying evenly is.
Can I carve or stamp the outside?
Yes, and a cut box is the best surface in the studio for it, because a design carried across the join lines up on both halves. Do it before you cut, while it is still one object. The carving and sgraffito page covers depth, timing and how not to cut through a wall.
Last thing
Cut it, and the hard part is already behind you
That is the working version
Every other lid you will ever make asks you to reproduce a number. This one asks you to draw a straight line and hold your nerve for four walls. That is a much smaller ask, and it is why we point people at a box when they say lids have beaten them.
Your first one will have a lid that only goes on one way round, and you will be glad you scratched that mark. Your second one will be square. Your third one will have a clasp on it, and somebody is going to keep something they care about inside it for the next forty years.
Slabs at three eighths, wait, build it closed, wait, cut it, lip inside the rim, dry closed, wax both faces that touch. That is a box.
There is a much longer version of this page, with the anatomy drawing, the four kinds of box, the wheel method, eight videos and every way we have watched this go wrong. The toggle at the top switches to it any time.
Keep going
Which version would you like to print?
Videos come out as a labelled box with the title and channel to search for, since paper does not play them.