How to Build a Waterfall Table

It's a tale as old as time. You've just settled in for a nice lazy Sunday nap when you hear: "Hey Paw! I reckon that dang ol' tree done gone fell on the outhouse!" And now you have a mess on your hands. Well my friends, I'm here to tell you that you can turn that tree into something neato.

This Instructable will start from a tree and end with a finished table, just because that's how this particular project went for me. To spare you the boredom I won't be going into detail on a lot of steps, since some of them could be their own writeup.

If you're starting with an already dried and planed wood plank this table can actually be a fairly quick and easy project that can be handled by most people with a few common tools.

So what do you say we get started, Vern?

I'm going to fly through this section because it's certainly much easier and faster to purchase a wood slab. But since I'm a card carrying hillbilly I have to make my own.

The very first step is to find a tree. I was fortunate enough to know a guy who told me about a big walnut tree that was going to be removed and chipped up as part of a stream rehabilitation project. One person's trash, am I right? You can basically use any type of tree/wood for this table, I just happen to have gotten walnut. So after cutting the tree down and hauling it to my house it was time to get slabbin'.

I used a chainsaw mill to cut that giant mamajama into 2.5" slabs, knowing I wanted the finished table thickness to be roughly 2". After cutting the wood into slabs it needs to be dried. There are a few ways of doing this; you can drop it off at a local lumber dryer and they put it in their dryer for a fee, you can build a homemade drying shack or simple tarp operation, or you can just stack the lumber and let it air dry. I don't mill enough lumber to have the first two options make sense, so I went with the air drying method. The short story is you just stack the planks on top of each other with a spacer in between them, but if you're going to do this you need to research it more because there are a lot of details that go into this procedure. Now the general rule of thumb for air drying is you need to wait one year per inch of thickness in the slab. But aside from being fat, ugly, balding, and impatient I'm also very impatient. I had the log for a couple years but only had it cut into a slab for about a year. I know, I just said a year per inch thickness, thanks Mom. But being so impatient I decided to risk it and build the table right now anyway, if it has any severe warping or separating I can just fix it at that point. So try not to let this situation consume your every thought for the rest of your life, let's just move on to the next step.

Once you have your slab the next step is to flatten and smooth is out. I used a power hand planer to get rid of any saw marks and flatten out a tiny bit of cupping that occurred during the drying process. You can also use a hand plane or a router sled jig, if you're not familiar with a router sled just google it, it's your best option using a pretty common tool. You don't have to get everything perfectly flat or smooth at this point because you will probably plane or at least heavy sand again after the next step. Once you have everything planed sufficiently it's time to fill any knots, splits, and cracking with epoxy. Use some tape (foil tape is the cat's pajamas) to dam up anything you're filling on the edges, and use some putty to make a dam if you want to minimize the runout you will need to sand later. I'm also making two walnut end tables at the same time as the coffee table, and I experimented with adding black paint to the epoxy on one of the end tables and it turned out pretty neat, I might actually do this for splits and cracks from now on, but I will always use clear epoxy for knots since that's the best looking part. If you're not familiar with using epoxy you need to look into that a bit more before using it, I'm not going to go into detail here. Once the epoxy cures you need to remove the excess to get it back to flat. You can use a planer, a sander, or a card scraper, anything that will get you back to flat because you will need to eventually sand all of this smooth.

As you can see from the title picture this table has a "waterfall" edge, which is the grain of the wood continuing from the top down the leg. You don't have to do a waterfall edge, you can just make a different type of leg, but then why are you even reading all of this? If you don't want to go chasing waterfalls please stick to the rivers and the lakes that you're used to.

The first key point to making the waterfall edge look good is to pick a spot in your slab where the grain is relatively straight. Since you will be losing at least a sawblade width of wood when you cut it the straighter your grain is the better it will match when you join them back together. I'm not sure how to explain that any better, but the more curvy your grain is where you make your cut the further off the grain will be from matching the top and the side.

To make the cut I used a circular saw and a sharp fine blade. You will want to use a straightedge of some sort, don't dare freehand this because any slight wiggle will be noticeable when you join the two pieces together, this should hopefully be your finished joint cut. Set your saw to 45 degrees and cut slow, don't force it, but don't burn it. You may want to put a piece of masking tape or something along the cut to help prevent the top side from chipping out. One you have your first cut made you will take the other piece that is now at a 45 degree angle in the wrong direction and cut a wedge out of it to make it 45 degrees in the correct direction so that the two pieces join together to make a clean 90 degree corner with the grain continuing from one piece to the other. I really wish I would have take some better pictures to help explain that word salad I just threw out there, but let's be honest, no one is even reading this garbage anymore.

Once you have both of your cuts made you can dry fit the pieces together to see how clean and straight your cuts were. If you have any issues with your cut now would be the time to try to correct it. If you need to cut it again obviously take just as little off as possible because the more you remove the more it will screw up the grain matching up between the two pieces.

Once your two matching 45 degree cuts are made it's time to assemble the waterfall joint. I used a few biscuits in my joint to help align it in clamping and maybe add a little bit of strength to the joint, but you don't really have to do this if you don't have a biscuit cutter. You could also use dowels or other wood splining methods, but again, you probably don't really need to, especially if you are adding the angle support that I will get to in a little bit.

So get yourself a good wood glue or epoxy, spread that stuff on both edges of your miter, and clamp that baby up. Take a look at the clamping configuration in the pictures, I won't bother to try to explain this. This clamping setup allows you to get a good tight fit at your miter by applying correct pressure from each clamp. Use scrap wood between your table and the clamps so that you don't leave indents in your table. The goal is to get the two edges of your mitered pieces to meet at a point and have that point be very tight with very minimal gap.

Confession time: I screwed up my joint the first time I assembled this. When I first made my cuts they were very slightly off from exactly 45 degrees, and when I glued them up for some reason I was so concerned that this leg needed to be at exactly 90 degrees so clamped it at exactly 90 with a few square braces and I ended up with a terrible joint that had a huge gap along the whole thing. I know it was stupid, I'm not proud of it, but it happened. So I had to cut it apart and redo it. The whole reason for me telling you of my stupidity is to point out that it doesn't really matter if your leg doesn't form an EXACT 90 degree angle, the much more important aspect for this table is to get a good tight joint at that corner. Or the better advice would be to cut a couple 45s on some scrap lumber first to see if they match up to make exactly 90. So after adjusting my saw to exactly 45 degrees I cut it apart and re-glued the joint.

After everything was dried it just took a little more sanding to clean up the joint and finish the surface. I went up to 220 grit using an orbital. Don't forget to also sand your live edges, and don't even think about leaving any bark on there, it'll just fall off eventually.

I'm no expert on finishing, so I would suggest doing some research and using your own experience to really hone in on how you want to finish your table. I personally think the only wood that should be shiny is flooring, and if you disagree I will challenge you to fisticuffs. So I knew I wanted a matte finish and through my research of walnut finishing I did a test piece using oil based poly, water based poly, and tung oil. I think the tung oil came out the clear winner for the look I was going for, but since tung oil isn't a very durable finish I applied a few coats of the oil based satin poly over three coats of the tung oil. The polyurethane is a much more durable finish, and since I have a crazy toddler, a messy baby, and a jerk dog I need a really durable finish. So do a little research into what type of finish you want for your type of wood and whatever look you're going for. You'll undoubtedly get 12 different suggestions from 10 different sources, so do some tests on some scraps or on the underside.

Once the wood is finished the last step is add the hardware then take a picture to share on The 'Gram you dirty hipster. You can do anything you want for the leg on the non-waterfall side, I decided to weld up a simple leg using some tube steel then spray painted that a flat black, nothing too flashy. You could even do a waterfall edge for both legs if that suits your style, I personally am a fan of asymmetry so I like the look of different legs.

The only other hardware I added was a heavy piece of angle steel to reinforce the waterfall joint. If you're the type of person that takes good care of your furniture and you don't have any kids running around you can probably get by without this. But I just know my son would try to impress me with his best Matt Foley impression and snap this thing in twain, so I need this to be extra sturdy. I drilled holes in the angle steel and used a bunch of lag screws to attach it to the table.