# How to make box tops/bottoms?



## Elizabeth (Oct 17, 2009)

I'm starting to make my first box joint box and realised that I have no idea how to make the top and bottom for it. I am making it with 1/4" thickness sides and 1/4" box joints. I had originally planned for 3/8" sides but after resawing the wood (another first!) one of the pieces was not quite thick enough for that. So maybe my sides won't be thick enough to cut a dado for placing top/bottom pieces. What methods of making tops/bottoms are open to me?

It's also recently occurred to me that since I plan(ned) on gluing the box up and then cutting off the lid, I should account for that in the layout of the box joints…right? How is that best accounted for when using a homemade box joint jig?


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## Blackie_ (Jul 10, 2011)

Elizabeth, you don't have any room for kerfs, about the only thing you can do here is either butt joint or box joint the side walls together, as for as the lid goes what I would do in this situation is cut the lid slightly larger then the box just slightly only then glue and clamp to the box once dried and cured next using a straight bit on router table with bearing guide trim the access off then cut the lid away.

Edit in; I just re-read and saw that you are using box joints, the bottom can be very tricky unlike mitered joints but since your side walls are only 1/4 think there's no room for a kerf/dado, so I'd just butt the bottom slab onto the bottom of the box and glue it in place, do it the same way as the lid only make it as a base leaving excess of 3/8" to 1/2" around the bottom of the box to act as a base bottom.

Adding a kerf to the bottom of a box joint box you have to use stop blocks on your router table as you don't want the kerf to go all the way through your box joints on your male ends as it would leave holes in the sides of your box, that's why I say it's tricky.

My method of making lidded boxes, I use 5/8" thickness walls and or 9/16 which is also good, on my open top boxes I use 3/8" - 7/16" side walls, but that's a whole different design as the walls are supported with an inner block, for a nice sturdy box you need at least 1/2" to 5/8" side walls.


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## Elizabeth (Oct 17, 2009)

Thanks Blackie. I think I might make a rabbet (piling up the first time jobs here!) around the bottom piece and glue it flush with the sides, and do the same thing with the top except leave it unglued as a piece I can lift off and on, and put a handle of some kind in the center of the lid.

Next time I'll do thicker sides so I have more options. I'm using a box joint blade to start with which makes joints of 1/4" and 3/8" width, and I heard it's good to have the side thickness match the joint width.


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## RichardHillius (Oct 19, 2013)

If the wood bottom and lid is stable a 3/32" groove should be fine and still leave enough material to support the rest of the piece. My only concern would be the panel shrinking out of the groove. I would probably lean on the tighter side when fitting the panel in that case and maybe only undersize it by a 1/16" or so from the overall groove dimensions. Wood species, grain direction, time of year and moisture content of the pieces of course might make me reconsider that.


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## knotheadswoodshed (Jun 14, 2012)

without knowing what your original plans were, you have a couple of options, if the wood was something really special that just ended up being too thin after planing, you could laminate another wood to the inside (say you re-sawed some nicely figure walnut, you could laminate a thinner piece of maple to it to make a thicker board, plane to 1/2" and proceed from there,which also adds an interesting contrast )

In general, I make 90% of my box sides 1/2" thick, this allows you to cut a 1/4" deep groove for the lid and bottom, and allows for almost any type of hinge you may want to use.

on the subject of grooves for box joints boxes, a great option is using a box slotting bit (Lee Valley) which enables you to cut the grooves without the need for stop blocks, you simply dry fit the box togather, clamp it to keep things tight and route the grooves, couldnt get any easier.

As far as cutting the lid, I make my cut centered between the joints on the face side (I also use 1/4" box joints), for best results, in my experience, you want to make your lid about 3/4 to 1"as this will help to minimize any warpage due to wood movement. (learned the hard way).

I hope this helps, if you have any specific questions feel free to message me and I will help as best I can.


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## Elizabeth (Oct 17, 2009)

The wood is maple, and really this is a skill-gaining project more than anything - if the whole thing never coalesces into a box, well I'll still have built a box joint jig and learned to resaw boards, do box joints, and learned how NOT to do tops and bottoms.


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## knotheadswoodshed (Jun 14, 2012)

for me, every box is a skill gaining project as there will always be something that didnt quite work out the way you had planned..hence my tagline "I dont make mistakes, I make design change opportunities"

the main thing is to have fun with what you are doing and learn new things


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## Blackie_ (Jul 10, 2011)

The other Randy had something there, I hadn't thought about doubling up on the wood but as he stated if you option to the inside of the box it's going to change your inner dimensions but if you laminate to the outside it's going to cover up your exterior unless you have more of the same wood.


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## Blackie_ (Jul 10, 2011)

Here is a bit of information in regards to making box joints and a great reference to reflect back too if in need, I find it a great bit of information and fall to it quite often.


*Gap.* A gap between each pin and slot is caused by the key that's too close to the bit/blade
*Too Tight.* If the pins won't fit in the slots at all, the key is set too far away from the router bit or blade. 
*Offset.* An offset can be caused by not having the workpiece fully seated against the key.


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## Elizabeth (Oct 17, 2009)

Laminating is definitely possible - I haven't cut the pins yet, I have two long (~25" each) surfaced pieces of maple and could easily put something else together with them before cutting them into the four box sides…even a different color and have two toned joints! I mostly have maple wood though, not sure if I have anything a different color of the right dimensions.

Those are great tips Randy/Blackie, and very clear - thanks!


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## waho6o9 (May 6, 2011)

Maybe make the bottom out of one piece and rabbet the perimeter
of it like this:









Have fun building up your skills and enjoy the journey!


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## Elizabeth (Oct 17, 2009)

That's exactly what I was thinking, Wahoe. And seeing that photo, maybe I could make a lid the same way using a double rabbet, one on the top and one on the bottom, and then adding a handle to the center of the top.

Lots of options coming up now!


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## Finn (May 26, 2010)

I make a lot of simple cedar boxes and have found that 3/8" thickness of sides works best for me. This allows me to install hinged lids with exposed hinges and the shortest screws for these hinges I have found are 1/4" so 3/8" thickness works well.


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## CharlieM1958 (Nov 7, 2006)

I frequently make the tops and bottoms of a contrasting wood species, and use Blackie's method. I cut them slightly oversize, butt glue them the sides, then trim with a flush-cut router bit.










For a simple lid that doesn't require hinging, I trim the top off the completed box on the table saw, and laminate a thin "keeper" lining to the inside of the lid or box:


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## DocSavage45 (Aug 14, 2010)

Elizabeth,

looks like you are in expert hands Would also suggest "Boxguy"'sb logs for more detail and Andy who did some of the original blogs on box building. Great stuff!


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## gfadvm (Jan 13, 2011)

Elizabeth, I really like for my boxes to have "feet". I would cut out the bottoms of your box sides to create "feet", the cut a piece of 1/4" ply to fit exactly inside the box for the bottom (hide small cleats inside the corners where the feet are to glue the ply to). That will answer the floor part of your box. For the lid/top, I would cut a piece 1" wider and longer than the box dimensions (leave 1/2" overhang all the way around) and then do a "Patron style" wooden hinge.


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