A friend of mine is building a tree house for Make-A-Wish and asked if I'd be interested in making a small table which looked like an actual lego brick ... with a light underneath to illuminate what sits on a bottom shelf, which is of course, a Lego creation of his own.
The first action was to find the actual dimensions of a four stud brick and as you can imagine, there are actual schematics ... then sketch up a design [See picture of said sketch in the section above].
Actual Lego Brick:
16mm long x 16mm wide x 9.6mm high
4.8mm stud diameter
1.6mm space between the stud and it's quadrant edge
I needed to convert the measurements to Imperial, since that's what I'm used to working with, as well as scale them down.
My non-precision Imperial conversion: 16" long x 16" wide x 10" high
Down-scaled to 75%: 12" long x 12" wide x 7.5" high
4" stud diameter
1" space between the stud and it's quadrant edge
Note: All measurements will be listed at the end of this Instructable.
Next step was to acquire necessary materials and while this project isn't sponsored in any way, I did speak with the Manager of my local Lowes and told him what I was doing. He asked me to make a list and graciously donated everything I needed. Not sponsored, but actions like those deserve recognition.
Materials: Full sheet of 3/4" plywood, two 1" poplar dowels, quart of latex paint (Safety Blue), small LED flashlight, package of springs, and some 1/4-20 hardware.
Step 1: Fabricating the Lego Block
I started with the main component, which is the Lego stud. With the exception of the subtop, it's constructed from 3/4" plywood.
I cut all of the parts to size, then added any necessary grooves, and lastly cut any miters. You'll notice the use of painters tape, which greatly reduces chip out of the veneer layer when cutting plywood.
Top Panel: 12" x 12" - three sides mitered.
Front Panel: 12" x 7.5" - 1/2" groove 3/4" down from the top edge - 3/4" groove 3/4" up from the bottom edge - 1 long side and 2 short sides mitered.
Side Panels (2): 12" x 7.5" - 1/2" groove 3/4" down from the top edge - 3/4" groove 3/4" up from the bottom edge - 1 long side and front facing short side mitered.
Once the box sides were cut, I used packing tape to dry assemble the box in order to get a measurements for the top and bottom panels, which mate into the grooves.
The final part was the sliding back panel, which employs a dado and rabbet. I used a scrap piece of plywood to set the fence distance and then cut a 3/8" wide and deep dado into the back face of the two side panels, as well as in the top panel. I then and nibbled away at the back panel rabbet until it was a perfect fit. Not too tight, but not too loose.
Step 2: Fabricating the Lego Studs
For the Lego studs, I decided on a thickness of 1", which meant I needed to start by laminating two pieces of 1/2" plywood. A healthy slathering of glue, a plethora of clamps, and then a clamp on a clamp to magnify said clamping strength, does the job. That's how it works ... right?
My Lego stud diameter was determined to be 4" and it just so happened I already had a hardboard template from a past project [The Drum Coaster Set]. I did a quick layout to maximize material, marked center holes, and drilled 1/8" pilot holes into the laminated plywood.
From there it was just a repetitive process, which moved rather quickly.
1. Screw the template to the plywood lamination
2. Cut the rough shape out using the bandsaw
3. Use a pattern bit on the router table to cut the final shape
I used this method to make five 1" thick discs, one 3/4" disc, and one 1/2 disc.
Step 3: Lego Stud Layout and Drilling
The easiest way to think about the stud layout, is to break the block down into quadrants. A 4 stud block has four quadrants ... in a 12" block, that equates to 6" x 6" quadrants .. that makes the center point 3" in from each side. Those points can be easily marked with a combination square set to 3".
Before drilling, it's important to have the 3/4" top and 1/2" subtop secured to each other, so that all of the holes aligned perfectly. I achieved this be first taping them together during the dry assembly and then using four screws to ensure then wouldn't slide around.
I started all for drilling locations with an awl, which I find greatly assists in guiding the drill bit. I then used these marks to drill pilot holes in the two back stud locations, so that I could temporarily screw a stud in place and trace the diameter. Once that was complete, it was onto drilling.
The front two studs are stationary and I'm only using pegs to appease my OCD. It'll be much easier to take a little time to drill centering alignment holes now, then it will be to wrestle with a combination square and a slippery, sliding peg during glue up. That being said, these holes are drilled using a 5/8" forstner bit and are around 1/2" deep.
The back two studs are mechanical and recessed into the 3/4" top, but they both have centered dowels, which extend down through the 1/2" subtop ... so we need to drill the 5/8" centered holes through both layers in this case. Per my usual MO, I drill down until the point of the bit just pierces the bottom, flip the panel over, and finish drilling the hole from the opposite side .. which eliminates all blowout. Try it ... you'll like it.
While I had the 5/8" bit in the drill press, I drilled most of the centered holes into the stationary studs. The mechanical studs have slight variations, which we'll cover shortly.
With all of the 5/8" holes drilled, it's time to enlarge the two back holes on the top panel to the 4" diameter outline. The top was separated from the subtop, the bulk of the material removed with a 2" forstner bit, and then sanded to the line using the oscillating spindle sander. I snuck up on the line until the studs easily fell into the pocket. I didn't want them too sloppy, but I didn't want they "bang on" tight either since paint will add some thickness.
Step 4: Lego Stud Mechanism: Twist Lock for Back Panel
The locking Lego stud rotates a length of 1/2" plywood in and out of a recessed slot on the back panel. The top of that pocket was marked by dry fitting the panel into it's mating rabbet on the top panel.
The start and stopping points of these pockets were drilled using a 1/2" forstner bit. You could just as easily cut one long groove across the panel, but I preferred the look of the pockets. The slots were then cut using a trim router and edge guide.
For the locking lever, I cut a 1 1/2" strip of 1/2" plywood, rounded the front corners, drilled a centered 5/8" hole, and then finessed the shape using the oscillating belt sander until I was satisfied with the fit and operation.
The stud is a 1 3/4" lamination - 3/4" to fill the excavated pocket in the top and 1" to sit proud and match the stationary studs.
Step 5: Lego Stud Mechanisms: Spring Loaded Light Switch
The light switch Lego stud is spring loaded and as you may have guessed .. it activates a light.
The stud is a 1 1/2" lamination, but the drilled holes are "stepped." The exposed 1" portion of the stud is drilled for a 5/8" dowel, but the recessed 1/2" stock is drilled at 3/4". This creates the necessary circumference, as well as a positive stop, for the captive spring.
The length of the centered 5/8 dowel is determined by gluing up the 1 1/2" lamination, adding a 1/2" spacer in the stud recess, and then cutting it flush to the internal surface of the box. The end of the dowel is then drilled for a screw, which will fasten a 1" washer to keep this mechanism from becoming a disappointing rocket.
The "switch housing" is fabricated from a fifth 4" diameter x 1" plywood lamination disc. The center hole is 1"' which is the perfect size for the Harbor Freight flashlight I'll be dissecting (this could easily be modified to fit your flashlight/switch of choice. The depth of the hole had to be adjusted for smooth operation .. so I don't have an exact measurement on that bad boy. Lastly, I created a slot/exit point for the wiring, by drilling successive holes using the drill press.
Step 6: Fabricating the Bottom Shelf and Tile
The bottom shelf is a 1 1/2 lamination of two separate 3/4" x 12" x 12" plywood pieces. I cut the 12 x 12 squares first and then added the 45 degree miters. The sides were made from offcuts ... ripped to 1 1/2" and then 45 degree miters on each edge. I will say that this is somewhat of an "advanced cut." It's not difficult, but it takes some practice and light, yet controlled touch. The left hand applies light pressure against the fence, while the right hand applies gentle forward momentum - always with push apparatus ... blocks, sticks, whatever. Too much pressure and things will bind and shoot back you you, which isn't good. A safer option would be using a 45 degree crosscut sled and cutting these parts from a wider panel.
Note: Before I cut the miters on the 12 x 12 panels, I found the center of each panel and drilled a shallow 5/8" hole, which was used for alignment during glue up. Instead of the panels slipping around, they locked around a center point and I just used the tabletop to flush one edge before locking them in place with brads.
The sides were then cut to length using the miter saw and attached with glue and brad nails.
The top tile is fabricated from 1/2" plywood and it has a dual purpose.
Purpose #1: Wall art
Purpose #2: Fits over the studs of the table block for more flat/useable surface area.
The top is another 12 x 12 square with 45 degree mitered sides. The sides were ripped to 1 1/2" depth with a miter on one long edge. Overall length miter cuts were on the table saw using a backing block to make the operation safe (a 45 degree crosscut sled would be an even better option).
For assembly, I used wood glue and brad nails. To thicken up the sides, I added another internal layer of 1/2" plywood, which registers nicely with the 1" offset between the Lego studs and quadrant edges.
Although it wasn't necessary, I added a centered stud to the underside of the tile. It's diameter is 4 1/2", which fits almost perfectly between the four block studs. It was rough cut using the bandsaw and then trued up using the oscillating belt sander. Once again I used my OCD method of a centered 5/8" stud for perfect alignment during glue up.
Once the glue was dry, I used the table saw to cut the overall depth to 1" and the drum sander to make all of the sides flush.
In order to hang this tile on the wall, I added some plywood blocking and then drilled out a shallow 1" diameter recess for my shop made keyhole washer, which a deeper 7/8" recess for the screw head. I plan on making a jig and video and Instructable on this method, but you can check it out in Step 5 of my "The Dog Walking Station."
Step 7: Fabricating the Legs
When I think Lego legs, I think Lego plungers ... am I right? I'm making the legs from 1" dowel stock and 2" dowel stock for the feet.
I decided to attach the legs to the Lego block using T-Nuts and bolts. I started by cutting the 1" dowel stock longer than necessary, marking center on one end, and drilling a 5/16" hole to accept the 1/4-20 T-nuts. The T-nuts were then set in place with 5 minute epoxy and a hammer.
While the epoxy dried, I moved onto the feet. Using a small parts crosscut sled on the table saw, with several clamps, I cut 2" sections from a 2" diameter poplar dowel. It was thrilling and a bit nerve racking ... mostly thrilling.
I marked the center of each foot and then drilled a 1" diameter hole to a depth of approximately 1/2". I then decided to add a small 45 degree chamfer to both ends of the foot because I foresaw them chipping out as the table was being dragged across the floor of the future treehouse.
Prior to glue up, I cut the legs down to their finish size ... overthinking match in 3 ... 2 ... 1
Note: Cut the side that doesn't have the T-nut ... otherwise, that would be bad.
Desired finish height = 24"
Block height = 7 1/2" - 1 1/2 for the bottom reveal and hole = 6"
+ 1 1/2" tile top = 7 1/2"
Foot height = 2" - 1/2" hole for foot = 1 1/2"
7 1/2" + 1 1/2" = 9" of used height
24" = 9" = 15" dowels
Glue up was just a matter of wood glue and a speed square to get things as "straight as possible."
Step 8: Layout and Drilling of Leg Holes
In order to drill aligned holes in the bottom shelf and Lego block bottom, I opted for a more low-tech approach. I offset the back edge of the block bottom by the thickness of the back panel and then centered it side to side. Once I had it as good as I could get, I strapped it all together with packing tape.
I marked the hole locations on the bottom shelf and drilled them out using a 1" forstner bit at the drill press.
Front Legs: 1 1/4" in from the sides - 1 1/4" in from the front
Back Legs: 1 1/4" in from the sides - 1 1/2" in from the back [This accommodates for the sliding back panel]
It became clear that I needed a sub bottom panel ... both to create a way to secure the legs and also to conceal wiring. This was cut to fit snuggly inside the Lego block. During yet another dry assembly, I transferred the leg centers to this panel using a 1" forstner bit and then drilled those holes out using a 1/4" bit.
Step 9: Fabricating the LED Circuit
For the LED light, I'm cannibalizing a free Harbor Freight flashlight. It's a sleek design in a nice 1" diameter. It's also aluminum, so it cuts easily using a bandsaw. I unscrewed the switch, removed the battery pack, and cut off the LED ... making sure not to cut into the circuit board. I then cleaned up my rough edge using the oscillating belt sander.
Many steps back, I found the center point of the block bottom and drilled a 1" hole for this very purpose.
I could've soldered wires directly to the battery pack, but I decided to make a "dock" to make changing the batteries more convenient. There wasn't much of a plan ... I just designed it on the fly. I made the two end pieces first and threaded a carriage bolt with a washer into each. Using glue and pin nails, I secured these to a 1/2" plywood bottom and back .. notice I used the actual battery pack to achieve proper spacing.
Once the glue cured, I cut everything nice and pretty using a small parts crosscut sled on the table saw and added grooves to the back for wire runs.
To wire up the circuit, I used some speaker wire I already had on hand and started in the middle. The flashlight is a pretty simple circuit once you dissect it.
Wire #1: Switch -> battery pack -> LED
Wire #2: Switch -> LED ... by way of the aluminum body
Starting in the middle, I separated the two wires and cut one in half [the solid wire in my case]. Each cut end was stripped, wrapped around the carriage bolt of the battery dock, and tightened in place under the washer.
Next, one end goes to the switch and the other goes to the LED. Lengths where determined by yet another dry assembly.
Switch (feed the wire through the switch housing before soldering ... or you'll be using a chisel to make a trench)
The solid wire gets soldered the spring.
The striped wire gets soldered to a hole drilled in the aluminum body.
The solid wire gets soldered to the circuit board.
The striped wire gets soldered to a hole drilled in the aluminum body.
I used hot glue to cleanly secure the wires to the back of the battery dock, as well as to secure the switch to the bottom of its hole.
Step 10: Internal Wire Management
You could leave the speaker wire to hang free or hot glue it directly to the box interior, but I decided to overthink things and cut wire runs using a trim router. A 1/4" straight bit and a speed square as a fence made quick work of this task.
As with the back panel slots, I cut the wire runs for both sides ... just in case the owner ever wants to swap the mechanical pegs around to work better with room placement.
Although not necessary, I decided to add some alignment pegs to the sub bottom panel, as well as a stop for the sliding back panel. This was accomplished using a Festool domino machine. The same results could be achieved with dowels.
The "sub bottom" was cut to exact domino width and the block bottom was cut using a wider setting in order to accommodate for any error. The fence maintained equal distance from the back edge.
The back panel was just a single cut to accept a domino, which acts as a stopping pin ... keeping the back panel from falling out and smashing onto the floor when unlocked.
Step 11: Glue Up and Putty
Since I had cut all of the parts to be interlocking, glue up was amazingly straightforward. It was still a bit mess and not flawless, but low stress all things considered.
1. Add a small amount of glue to the top and subtop. The screws took care of most of the alignment and clamping pressure, but I added a few brads to the center as well.
2. Align the front and sides using packing tape, add glue to the grooves and miters, fold them up around the top and bottom panels. Squeeze all the joints tightly into place and add brads and necessary.
3. Secure the two front, stationary studs with glue and brads.
Once the glue cured, all nail holes and inconsistencies were filled with wood putty.
Step 12: Sanding and Finishing
Since I used good quality plywood, there really wasn't much sanding to be done. It was mostly sanding the wood filler flush and breaking the sharp edges.
The 1" dowels ended up being a bit too tight for the 1" holes, so I used a length of 1/4" threaded rod and a nut as a peg, which would be chucked into a drill. Then it was just a matter of running sandpaper down the length of the spinning dowel until it was an adequate diameter.
Once the glue cured, I used black leather dye for color, followed by two coats of water-based polyurethane.
The top block, bottom shelf, and tile were sealed with shellac .. followed by two coats of latex paint. The mechanical stud cavities were masked off and I lightly sanded between coats.
Paint Color: Safety Blue
For the legs, I used black leather dye, followed by two coats of water-based polyurethane.
Step 13: Final Assembly
All the time spent on fabrication pays off during the final assembly ... at least that's what I choose to tell myself. Prior to assembly, I added paste wax to the mechanical stud recesses and stud bottoms, as well as to the dadoes and rabbets of the sliding back panel.
Light switch stud: Slip the spring onto the 5/8" dowel/peg and insert it into the desired block location ... it will most likely not cooperate and cuss words will be slung. Once it work out, secure the washer and screw to the dowel from inside the box.
Locking stud: Insert the dowel/peg into the desired block location, slide on the 1/2" plywood locking lever, and secure it with a screw to keep it from spinning on the dowel.
Battery dock: Attach the dock to the center of the front panel with a single screw. Make sure you screw isn't too long or you'll be in for a surprise.
Switch housing: Center the switch housing over the spring loaded screw and secure it with screws. I used three screws and all the holes were drilled using the drill press. just don't put a screw through your wire and you'll be good to go.
LED: The LED is a friction fit into the 1" hole. If it was too loose, I'd just use a dab of hot glue.
All of the wires are spot glued into the wire runs with hot glue.
Leg feed: The legs are feed through to the bottom shelf and then into the bottom holes of the top block.
Sub Bottom: The sub bottom panel is popped into place and secured to the actual bottom using a total of eight pan head screws (two in each corner). If these aren't added and someone were to sit on this table ... it wouldn't be good.
Securing Legs: 1/4-20 hex head washer screws are then fed through the bottom panel assembly and screwed into the embedded T-nuts.
In order to lock the bottom shelf in place, I a countersunk hole into the bottom of each foot, drilled a pilot hole up into the shelf, and then secured it in place with a 2" screw.
The back panel is slid into its rabbet and the "stopping pin" is friction fit from the inside.
Step 14: Glamour Shots
There we have it ... one Lego table fit for the young King of a treehouse. If I'm able to acquire some pictures of the table in kingdom, I'll be sure to add them.
Small table ... Check
Looks like a lego ... Check
Has an illuminated bottom shelf ... Check. That wil also function as ambient light in a treeshouse.
Blue ... Check
Mechanical lego studs ... Bonus
Hidden storage/battery changing compartment ... Bonus
Wall art/flat tile to transform the top into a more practical table surface ... Bonus
Top: 3/4" x 12" x 12"
Sub Top: 1/2" x 11 1/16" x 10 13/16"
Front: 3/4" x 12" x 7 1/2"
Sides (two): 3/4" x 12" x 7 1/2"
Back Panel: 3/4" x 11 1/16" x 7 1/16"
Top: 3/4" x 12" x 12"
Bottom: 3/4" x 12" x 12"
Sides (four): 3/4" x 1 1/2" x 12"
Top: 1/2" x 12" x 12"
Sides: 1" x 1 1/2" x 12"
Leg Dowel: 1" Diameter x 15"
Food Towel: 2" Diameter x 2"