Workshop Wednesday: Make your own coffee table
1. First, gather your supplies.
We used douglas fir which while not a typical furniture building wood works just fine and is pretty cheap. The wood for this project cost us about $60. Oak, cedar, or ash would be great choices as well. If using a fir or pine or any softwood, it’s best to let it sit and dry and acclimate in your shop area before using it to minimize the chance of the wood warping. Hardwoods are typically sold well-dried, but check with your lumber yard to see what you are working with.
We used 1x6 boards and got (5) boards that were each 8 feet long. You will eventually be cutting these down so that you have (8) 36-inch long boards for your table top and table bottom and then (3) boards that are 20 inches for your table sides and center support beam.
You'll also want some legs of your choice.
We got these cool steel legs from hairpinlegs.com but soon you'll be able to make legs like these at Houston Makerspace (stay tuned for more metals classes on our calendar!)
2. Rough-cut your boards down to size using the miter saw, leaving 4-6 inches of extra length on each one to leave wiggle room.
Since we want (8) boards to be 36 inches finally and (3) to be 20 inches, we cut (8) boards to 42 inches and (3) 26 inch boards.
You will cut your boards down to final size later.
3. Make sure the edges of your boards are complete flat using a joiner, planer, and table saw.
Use the joiner to flatten 2 sides of each board (1 long, thin side and 1 long, broad side), guiding the board through carefully with a push board. Mark each board as you go with pencil, noting which sides have been flattened.
Next, use an electric planer to flatten each board's other broad side.
Finally, use the table saw to straighten out the last remaining narrow side. (See our last Workshop Wednesday post on how to cut with the table saw for pointers here).
Note: You may be tempted to use the joiner to flatten all the sides, but don't! Doing that will give you 4 smooth surfaces, but they won't necessarily be squared and parallel.
4. Lay your long boards out and decide which will be on the top and bottom.
Make sure your boards fit neatly together - play with the arrangement to get the best fit and have the nicest boards on top. Once you have an arrangement you like, mark your top boards in pencil, numbering them so you remember what order they belong in.
5. Now you will cut your boards down to size with the miter saw.
We made our (8) tabletop and table bottom boards 36 inches and our (3) crossbeams 20 inches long.
6. Next, you will use the table saw or a router to cut grooves into your long tabletop and table bottom boards, one on both sides and one in the center.
Your (3) support boards will fit into these grooves, creating dado joints that look like this:
The grooves will be the depth or smallest measurement of your boards (in our case, after joining and planing, our boards were 3/4 inch deep).
To do this, set your table saw fence to the width of your beams (we used 1x6 boards, so our boards were 6 inches wide) and set the saw height to half of that smallest measurement of the boards (so we set our saw height to half of 3/4 inch).
You’ll be making several passes to eventually get the slot down to your final width. A table saw sled will ensure that all of your cuts are parallel.
For your side grooves, start at the inside and work your way towards the outside of the board.
For your center grooves, cut the 2 sides of the groove first, then make several passes to hollow out the center of the groove
There are special saw blades that will do this in one pass, but you don’t need to get that fancy for this project.
Make these 3 grooves on each of your (8) tabletop and table bottom boards.
7. If your grooves need to be cleaned up, use a hand file, a piece of sandpaper wrapped around a stick, or a Dremel tool to knock out any left over wood bits.
8. Dry fit your table to make sure all the support boards fit into their grooves - if not, file them/ clean the grooves up a bit more.
9. Get your four bottom boards into place and use big clamps to hold them tightly together in place.
10. Wood glue your center support board into place.
Squeeze a little glue into the center grooves of your bottom boards + along the long, thin sides of your support board. Press the support board in with your hands. You can also tap it into place with a mallet. Make sure to clean up any wood glue that oozes out!
11. With your support board in place, glue your top boards into place.
12. Next, glue your your side support panels into place.
13. Use more large clamps to clamp both of your side supports into place.
Use some thin scrap pieces of wood to buffer your boards from the clamps and to evenly distribute the clamp's pressure. Allow to dry at least overnight.
14. Sand all of your flat surfaces with a sander. Start with 100 grit paper and work up to 220, or however fine you'd like.
15. Now, apply your stain of choice. Foam brushes are the best for this.
16. To seal the stain, we used Minwax Wipe On Polyurethane.
Use at least two coats. The first one will largely soak into the wood. Let the first coat dry at least 12 hours or so, sand with 220 grit or finer sandpaper, then apply the second coat. Repeat until it’s as shiny as you’d like.
17. Add your legs.
First drill some small pilot holes and then drill the legs into place with screws. On most wood furniture projects you probably wouldn't want to use a power drill (you might mess up your wood) but these legs have a metal plate that will keep the drill from busting through.
Make sure that you use correctly-sized screws so that they don't bust through your boards.
Now invite your friends over for come coffee and brag about your new DIY table.
In addition to being the Houston Makerspace Metal Shop manager, Mike Dadeks is an electrical engineering student at UH. He loves using projects like this to teach himself how to woodwork. Stay tuned for classes in basic furniture building with Mike on the Houston Makerspace calendar.