This Instructable will cover each step of the build from the design phase, to building the sliding tile mechanism, to applying the last coat of finish. I have tried my best to document each step and to provide any hints and tips that I may have learned through the build process so that you can hopefully follow these instructions to build a Sliding Tile Secret Compartment Table of your own. Enjoy!!
General Information about this project:
- Table Dimensions: 33" Tall X 30" Long X 30" Wide
- Number of Compartments Concealed: 3
- Compartment 1: The compartment accessed by successfully aligning the sliding tile puzzle
- Compartment 2: The compartment located under the false bottom in compartment 1
- Compartment 3: A secret drawer hidden in the apron of the bottom shelf
- It's fun to make and fun to play with.
- Everyone likes puzzles.
- Because it is actually pretty easy to build despite the fact that it looks very complicated.
- In building this table you will learn tricks and techniques that might be useful in future projects.
- Because you'll learn how to build several cool jigs that might be useful in future wood working projects.
- It would be a great addition to your home i.e. it looks nice.
- Because secret compartments are cool and this table has 3 of them which makes it extra cool
- Because you would pay twice as much to buy a table that wouldn't do ten percent of the cool things this one will.
- Because if you're like me, any reason to be in your workshop is a good reason!
Step 1: Tools and Materials
- 3/4" Plywood Sheet (4' X 8') $55 - Available at home improvement stores like Lowes and Home Depot. You'll be able to get most of your table parts out of this sheet.
- 1/2" Plywood Sheet (4'X4') $25 - Also Available at home improvement stores. You'll be cutting this into four 2' X 2' sections to create the floor the tiles slide on, secret compartment bottoms, and the bottom of the hidden drawer.
- 1/4" Plywood Sheet 2'X2') $5 - Used to create the raised numbers that adorn the tiles.
- Hard Wood Boards ( 1" X 4" X 8') $14 - Used for making trim, I used red oak because I selected oak plywood to build my table.
- Table Legs $25 - I salvaged the table legs used for this project from an old maple table. I was able to cut the legs down into 1.5"X1.5"X28" lengths which was exactly what I needed for this build. If you can't find legs to salvage you can purchase pre-made table legs from home improvement stores and from Amazon.com
- 3 Maglocks $15 - I used Dream Baby Mag Locks which are intended for childproofing cabinets but work amazingly well for creating secret magnetic compartments that are completely undetectable. you can find a pack of 4 Mag Locks on Amazon.com for about 15 dollars.
- Three 3/4" X 1/16" Neodymium Magnets $7 - These will be what trigger the Mag Locks to open the secret compartments. The magnets will be installed in the bottoms of the sliding titles in key locations so that when the tiles are in the proper places the secret compartment will be able to open. Magnets will also be used to create a special magnetic key to open the secret drawer hidden in the apron of the table shelf.
- Hinges $12 - The type of hinges I used for this build were Richelieu Frameless Cabinet Hinges. These are the perfect hinges for a secret compartment build as there are concealed within the compartment so you don't have to worry about the giveaway of having visible hinges on your secret compartment.
- Drawer Slides $20 - Used for mounting the secret drawer in the shelf apron.
- Wood Glue $3 - I use Tite Bond Original Wood Glue which is available at home improvement stores like Lowes and Home Depot.
- 2 Butt Hinges $3 - Used for creating the hinged joint that allows the false bottom to fold up so that it can be removed.
- 5 Minute Epoxy $3 - Used to glue the neodymium magnets into the bottoms of the sliding tiles.
- Screws $4 - No real size/length requirements here, simply use the type of fastener that is best suited for the task at hand. For this project I bought a 500 piece variety pack of screws from Harbor Freight which served me well.
- Wood Filler $6 - For filling any gaps or dents in the table and for creating the bevel on the numbers that adorn the sliding tiles.
- Wood Trim $8- Used to conceal unsightly exposed plywood edges. Available from Lowes or Home Depot, or if you have access to a router you can custom make your own.
- Wood Stain and Polyurethane $12- My chosen methods of finishing wooden projects, you could however paint, shellac, or oil finish your table. One of the great things about wood working is the multitude of finishes that can be applied to enhance the natural beauty of the wood.
- Wood Biscuits $10 - These aren't necessary but if you have access to a biscuit joiner they are pretty useful as they add a lot of strength when gluing the different table parts together.
Note that many of these materials can be acquired for far less money then it would cost to buy them from the store. Hinges, Table Legs, Drawer Slides and Even Wooden Trim can all be salvaged from inexpensive flea market or thrift store furniture for a fraction of the in store cost and only a small investment of time. Most of the materials I had on hand were salvaged from furniture that students threw away last year when the local college let out for the summer break.
Note: You can complete this build without many of the tools listed below. Tools like the Scroll Saw and Router were used for decorative details and depending on how you wish to make your version of this table they may not be needed. Tools that are absolutely necessary for this build will be marked with a *.
- *Table Saw equipped with a standard 1/8" kerf blade
- Masking Tape
- *220 Grit Sand Paper
- 400 Grit Sand Paper
- Wood Chisels
- Utility Knife
- Scroll Saw
- Band Saw
- *Small and Large Wood Clamps
- Paint Brushes
- Carbon Paper
- Router or Router Table (Used to make custom trim; optional but useful)
- Biscuit Joiner (Optional but useful)
- *Hand Drill
- Countersinking Drill Bit
- *3/4" Forstner Drill Bit
- *1-3/8" Forstner Drill Bit
- *Phillips Driver Bit
- *Tape Measure
- *Compound Square AKA Tri-Square - (One of my favorite tools, I used this tool at least 100 times on this build doing everything from measuring parts to setting blade height and fence distance on my table saw. If you don't already own one of these I highly suggest picking one up asap.)
Step 2: Design
Modeling the table was extremely beneficial. The 3D models I created allowed me to experiment and make changes to my project so that I wouldn't have to waste time and materials testing things in real life. The models also gave me a good sense of what the finished project was going to look like and best of all I was able to build the table to scale in Sketch Up meaning that when the model was complete I was able to use measurements from it to cut the parts I needed to build the actual table.
Check out the pictures in this step for some insight into the design process and to get an idea of how the table functions.
Something else worth noting as it relates to design is the way in which the table was assembled. Basically I started ths project by making the sliding tiles and then built everything else based on their dimensions. As such, this instructable starts by showing you how to make the tiles. Once the tiles are constructed the way in which to approach the other steps can vary, for example you can build the bottom shelf and hidden drawer at any point during table construction. In some steps you may notice that parts of the table have been built that haven't yet been discussed, this is because I jumped forward in the build while waiting for things like parts to arrive or glue to dry. Don't worry if you see a step where something is done slightly out of order, that part of the build is most likely covered in a later step.
Step 3: A Word on Mag Locks
What makes Mag Locks so great for hidden compartments is that they are completely invisible when installed so anyone inspecting the table will have no idea what the mechanism is for opening the secret compartment or that there is even a secret compartment in the first place. Also they use magnets and I think we can all agree that anything actuated by magnets is pretty darn cool.
The Mag Locks will be used in two ways on the Sliding Tile Secret Compartment Table. The first way has to deal with the sliding tile mechanism; magnets will be installed in the underside of two of the tiles and Mag Locks will be installed on the underside of the floor the tiles slide on. When the tiles with magnets slide into position above the Mag Locks the Mag Locks will disengage allowing the secret compartment to open.
The Second way the Mag Locks will be use will be to lock the secret drawer hidden in the shelf apron. The installation for the drawer lock will be similar to how the Mag Locks are met to be used to lock cabinets, as such the drawer will need a special magnetic key in order to open.
Check out the include pictures to see the different parts of the Mag Locks and a few examples of them in action on the finished table.
Step 4: Cutting the Parts
These are the same cut schematics I used when building my table and I'm happy to report that everything went together with no trouble and I still had a sizable piece of the 3/4" plywood left over for future projects. With most wood working projects I'm a cut as you go kind of guy, but for larger projects like this I like to plan everything out so that I can make the most out of my time and materials.
Step 5: Making the Tiles Part 1
What is a Sliding Tile Puzzle?
For the Sliding Tile Secret Compartment Table you will need to create 15 sliding tiles from the 6" tile blanks that were cut from the sheet of 3/4" plywood in step 4. Continue on to steps 6 and 7 to learn how to cut the tongues and grooves using a table saw and a standard 1/8" kerf saw blade.
Step 6: Making the Tiles Part 2: Cutting the Tongues
This time set the saw so the blade height is 1/2" and so the distance from the inside edge of the blade to the fence is 5/8". With everything set correctly run your tiles through again, only this time stand them vertical against the tafence so that when the blade cuts into the wood it meets the cuts you made previously. As before you will need to make this cut 4 times to each tile, twice on the front and twice on the back, to establish the thickness of the tongues, which if you have set your saw correctly should be 1/4" thick.
If this explanation is a bit hard to follow consult the cut diagram included in this step for a visual of how the saw should be set up to make the tongue cuts.
Once you have all of the tile tongues cut continue on to the next step to learn about cutting grooves.
Step 7: Making the Tiles Part 3: Cutting the Grooves
Tip: The reason that you set the saw blade slightly above 1/2" is to give the tongues a bit of extra clearance as they slide through the grooves. You can see examples of this in the pictures on this step.
Tip: Test the fit of the tongues and grooves on the first tile you cut grooves into. If the tongue is tight within the groove it is much easier to fix the problem now as opposed to finding out the tongues and grooves are to tight after you have cut grooves into all fifteen tiles. If the fit is to tight simply move your fence slightly closer to the blade and make the cuts on both sides as before. Moving the table saw fence closer to the blade will lessen the amount of wood on either side of the grooves thereby making the grooves wider which will in turn give the tongues more clearance to slide through them.
Step 8: Decorating the Tiles
- Making the Numbers: To make the numbers I started by creating a word document with the numbers 0-9 typed in French Script MT font at a size that would properly fit onto the tiles. I then printed the document and used carbon paper to trace the numbers onto pieces of 1/4" thick plywood. Note that I had to trace several of the numbers more than one time, for example I needed eight number 1's to create the the numbers 1-15. Once I had all the numbers traced onto the 1/4" plywood I went to work cutting each number out with my scroll saw. When all the numbers were cut out I sanded them to remove any rough spots created during cutting.
- Attaching The Numbers to the Tiles: Once the numbers had been cut out and sanded I affixed them to the tiles using wood glue. Note, make sure that you glue the numbers to the tiles in the correct orientation, the tiles only fit into each other and into the frame one way so if you don't pay attention you might end up with a few tiles that look like they are upside down or turned 90 degrees because the numbers were glued on incorrectly.
- Applying Wood Filler and Sanding:After the glue has cured the next step is to use wood filler to create a bevel where the edges of the numbers meet the faces of the tiles. The wood filler bevels are purely aesthetic but they do make the tiles look nicer as the flowing transition of the wood filler bevel looks more intention than the stuck on look of simply gluing the numbers in place. Once you've coated all the number edges with wood filler use your finger and a bit of water to smooth the wood filler so the all the bevels look even, then remove excess wood filler and allow the filler to dry and set. When the wood filler has finished drying, give everything a good sanding to even out the surfaces in preparation for painting.
- Painting and Finishing. Painting was pretty straight forward, Using acrylic paint I painted the faces and edges of each tile one solid color. Half of the tiles were painted white and half green so that the colors alternated creating a checkerboard pattern. Once the first coat of paint was dry I highlighted the numbers on green tiles with white paint and the numbers on white tiles with green paint. Lastly I finished each tile with 3 coats of spray semi-gloss polyurethane.
Step 9: Making the Sliding Tile Frame Step 1 Assembling the Frame
Once you have the tongues and grooves cut on the frame pieces the next step is to measure the frame pieces so that they are the right size to hold the tiles, and then to miter the corners of the frame pieces at 45 degree angles in preparation for assembling the frame and gluing it together.
Because each tile has a 5.5" square face the inside edge of the mitered frame pieces needs to measure 22". (4 tiles across multiplied by 5.5" per tile = 22") Because the tiles will be moving within the frame it is advised that you add 1/16" to 1/8" to your measurements to give the tiles a little wiggle room, so instead of cutting your miters so the inside edge of frame pieces equals exactly 22", you may want to cut them so the inside edges measure something like 22 and 1/8". Miter all four frame pieces exactly the same length so when they are put together to form the frame you'll end up with a perfect square.
With the frame parts cut the next step is to start putting everything together. Start by gluing together 3 of your frame pieces leaving one frame piece unglued so that you can install the sliding tiles. (Installing the tiles and attaching the last frame piece will actually be one of the last steps of this build so it is very important that you do not glue the last frame piece in place right now, instead use tape to hold it in place to make sure the other three frame piece dry at the correct angles.)
Step 10: Making the Sliding Tile Frame Step 2 Attaching the Frame Bottom
With 3 of the frame pieces glued together and the forth piece taped in place the next step is to install the floor that the sliding tiles will slide across. This floor is made from one of the 2'X 2' squares of 1/2" plywood that was cut during step 4. Because the inside area of the frame measures 22"X 22" and the 1/2" plywood square measures 24"X 24" you will be able to overlap the plywood square over the frame 1" on all sides for attachment purposes. Line up the 1/2" plywood square so that it overlaps the four frame pieces equally and then use wood screws to affix the 1/2" plywood square to the three glued frame pieces remembering not to screw the unglued frame piece into place.
At this point you can put your tiles into the frame to test how they slide past one another. Simply un-tape the loose frame piece, install the tiles into the frame and tape the loose piece back in place. If everything works well then you are ready to move on to the next step.
Step 11: Making the Table Body and Legs
4 Table Legs
3 Shelf Aprons
Once you've created two of the sub-assemblies, the next step is to connect the two sub-assemblies using the 2 remaining aprons and the one remaining shelf apron (we're only using one shelf apron here because the other shelf apron will become the front of the hidden drawer in a later step.) Once everything is biscuit jointed and glued together use bar clamps to hold everything in place until the wood glue has dried.
Step 12: Attaching the Table Top to the Table Body
Note: In later steps you will notice that the tops of the table legs have been chamfered (angled) so that they are thinner near the top. This was because the table top was jamming against the table legs which was preventing the table top secret compartment from opening. Although this wasn't planned it was necessary and reminded me of something one of my favorite teachers use to say, "The mark of a good craftsman is not in how many mistakes they make, for even the best craftsman makes mistakes, instead, it is in how they recover once a mistake has been made."
Step 13: Making the Secret Compartment True Bottom and False Bottom
When the spacers have been attached you are basically ready to install the true and false bottoms, however, I advise waiting until later to install the two bottoms as they are easier to stain and finish before they are installed into the table. When it is time to install the bottoms, the true bottom will be installed by screwing it to the underside of the spacers, and the false bottom will simply set on top of the spacers where it can be easily dislodged to gain access to the compartment hidden below.
Step 14: Building the Hidden Drawer
Building the Drawer
Also note that the drawer bottom is one of the 2' X 2' pieces of 1/2" plywood that was cut back in step 4. You will need to alter the dimensions of this piece of plywood so that it fits within the confines of your drawer. For my drawer I used a technique for installing the drawer bottom known as the captive bottom method, for this method I cut 1/4" deep dados that were 1/2" wide in the front, back, and sides of the drawer and then installed the drawer bottom within the dados. For this method of installation I had to cut the drawer bottom to a side of 23.5" X 23.5".
Step 15: Cutting the Shelf Top
Once you have the wood removed from the corners so that the shelf fits in place, the next step is to install the Mag Lock mechanism before gluing the shelf top into place. (The reason you install the mag lock before gluing the shelf top down is that the mag lock catch needs to be installed onto the underside of the shelf which would be very hard to do with the shelf was glued in place.) Continue on to the next step to learn about installing the hidden drawer Mag Lock.
Step 16: Installing the Hidden Drawer Mag Lock
Step 17: Optional: Making the Mag Lock Key
- Select your block of wood. The wood I used to make the key came from an off cut of one of my table legs. The only things you need to consider when picking your block of wood is that it is large enough to conceal the magnet you are installing, and that it is long enough to safely cut on your table saw.
- Using the table saw, cut a section from the end of the block of wood that is no more than 1/16" thick.
- Next use the table saw again to cut away any unnecessary length from your wooden block so that you end up with a block of wood that is roughly a cube.
- Then mark the center of the wooden block and use a drill bit that is the same size as your magnet to drill a hole that is just deep enough for the magnet to set in it without sticking above the surface of the wooden block.
- Install the magnet into the hole and apply wood glue on the wooden surface all around the magnet
- Position the 1/16" section you cut from the block of wood earlier over the side of the block the magnet is installed into and clamp it in place until the glue dries, (Note, do your best to line up grain patterns as this keep the wooden block from looking like it has been altered.
- Lastly, once the glue has dried, sand the block until there is no evidence that the magnet has been installed.
There are several reasons why I chose to build the magnetic key in this way. First is that it is very inconspicuous, the key looks like a simple block of wood and would be quickly overlooked by someone trying to figure out the secrets of the table. Second, even if someone was to figure out that the wooden block was the key, they would still have the challenge of trying to figuring out which of the blocks 6 sides would work to deactivate the secret drawer Mack Lock, never minding the fact that they would have to find the location of the drawer front and the Mag Lock in the first place. All of this adds up to create a secret compartment that is amazingly hard to figure out and gain access too.
Step 18: Making and Installing Trim
How and where you apply trim is an aesthetic choice but I chose to install my trim in these locations:
- On the edges of the table top to cover the exposed plywood edges.
- On the bottoms of the aprons to change the straight edge of the apron into a gentle curving edge similar to the look of mission style furniture.
- On the edges of the shelf to cover the exposed plywood edges.
The trim I used to cover the exposed plywood edges of the table top and shelf is pretty standard and is something that you can pick up an any home improvement store, it's known as 3/4" cove trim or 3/4" cove molding. On the other hand the arched pieces I made to trim the bottoms of the aprons had to be custom made and the process for making these pieces was pretty interesting. Check out the pictures to see how that part of the trim was created.
Step 19: Installing Sliding Tile Mag Locks Part 1
To lock the table top shut we will be using Mag Locks just like the ones used for the hidden drawer. What makes the table top locks different from the drawer lock is that instead of using a special key to unlock the compartment, the locks on the table top will be deactivated when tiles with magnets installed in their bottoms are slid into place over top the mag locks.
Installing the locking mechanism is a pretty complicated process that involves transferring measurements between the table top, table body, and tiles to ensure that the Mag Locks and Mag Lock Catches line up correctly when the table top is closed. Follow the pictures, diagrams and instructions found on this page to start the table top Mag Lock Installation. Note that installing the Mag Locks that hold the table top closed is a two part process. the first part of installation will be covered in this step and the second part will be covered after stain and finish have been applied to the table.
Step 20: Finishing (Sanding, Staining, and Applying Polyurethane
Once you've finished sanding give the table a good wipe down with tack cloth to remove all of the dust from sanding in preparation for applying finish. As for how you apply your finish that depends on what finish you choose to use. for best results adhere to the instructions found on the particular finish you choose.
Step 21: Installing Sliding Tile Mag Locks Part 2
- Start by installing all the tiles into the table top.
- Next tape the loose frame piece tightly in place.
- With the first two steps complete use a piece of scrap wood to prop the table top open so that you can work on the inside of the secret compartment.
- Use the Mag Lock templates to mark the locations where the catch screws will go on the catch spacers.
- Once the catch screw locations have been marked, peel the adhesive backing from the template and close the table top. The adhesive will cause the template to transfer to the underside of the table top providing perfect alignment as to where the Mag Lock mechanism should be installed.
- When the template was transfer to the table top it was also flipped over meaning that you should now see the diagram of the holes for installing the Mag Lock, mark the locations of those holes but don't install the Mag Lock just yet. Note you can also install the Mag Lock Catches onto the catch spacers at this point.
- Position tiles above the locations where the Mag Locks will be installed; I chose tiles 13 and 15 so that my table would open when the numbers were put in ascending order but you could choose other numbers if you'd like to make opening the compartment a bit trickier. The tiles you position over the Mag Locks will be the key tiles that will deactivate the Mag Locks allowing access to the secret compartment.
- With the key tiles in position over the Mag Locks use a very small drill bit to drill through the center hole of the Mag Lock mechanism templates, through the sliding tile floor, and into the bottoms of the tiles. These holes will be used for aligning magnets that will be installed in the bottoms of the key tiles to the position of the Mag Locks.
- Now un-tape the loose frame piece and remove the two key tiles. You can also install the Mag Lock mechanisms on the underside of the table top at this point.
- Flip the key tiles over so that you can see the small holes that were drilled in their bottoms. Using these holes as guides, use a 3/4" Forstner drill bit to drill a hole just deep enough to hold a 3/4" neodymium magnet flush with the bottom of the tile.
- Scratch up the sides and face of two neodymium magnets with sand paper.
- Squirt some epoxy in the 3/4" holes and install the scratched magnets. The scratches made in the previous step will help the epoxy adhere to the magnets making for a stronger bond.
- Use clamps to hold the magnets in place while the epoxy cures.
- After the epoxy has cured, remove the clamps and re-install the tiles into the frame. With the mag locks installed on the underside of the table, slide the key tiles over top of them to deactivate the locks granting access to the secret compartment.
- If everything works, the sliding tile locking mechanism is complete!
Step 22: Putting It All Together
- Install the Sliding Tiles
- Glue and screw the last piece of the tile frame in place
- Screw the true bottom of the main secret compartment in place
- Drop the false bottom of the main secret compartment in place
- Optional: Make and install a table top prop out of a piece of dowel to hold the table top open, giving you easier access to contents hidden under the false bottom.
- Optional: Buy or make a custom glass table top to protect the sliding tile puzzle from dust and damage. Having a glass table top adds a lot of utility to the table as it makes the surface of the table flat so that it can function just as a normal table would, and when you want to use the puzzle or access the secret compartments all you have to do is lift off the glass table top and you're good to go.
A note on moving your table: Although you have probably already flipped and moved your table several times during the building process, it is still worth the time to discuss how to properly move it. The first rule of moving tables is to never lift from the table top and that rule applies ten fold to the Sliding Tile Secret Compartment Table. Instead, employ the help of a friend and together lift the table by holding onto the legs in order to move it to it's new home.
Step 23: Finished Project