DIY Tree Slice Table

Tree slices and slabs have been used as crude tables for centuries. While there are examples of elegant wood tables, such as those used by the Egyptian Pharaohs, which go back to about 2500 BC, those are unlikely the earliest tables built. Simpler tables had to exist before those, if for no other reason than to inspire the finer ones. Those tables could have been made of logs, lashed together, but that would provide a very uneven surface. Making a tabletop out of slabs or slices would have made sense, even though they might have been hard to build with the primitive tools of the day. But then, the Olmec people, who lived in Mesoamerica from 1600 to 350 BCE carved giant heads out of rock, using nothing more than other rocks as their tools.

This style of table has come back into favor amongst some groups since as far back as the 1960s, with it slowly gaining more and more popularity as people have looked for alternatives to traditional furniture styles. Slabs and slices are seen as a look that connects people closer with nature, helping to make up for the time we don’t spend in the great outdoors.

The one drawback to making tables out of slabs and slices is that it can be rather expensive to buy the raw wood itself. However, for those who have trees that need to be cut down, converting at least some of the wood to slabs or slices and then from there to furniture is a great option, which will add casual charm to their home, making their friends jealous while saving money on furnishings.

Before going on, allow me a moment to clarify some terminology here. Both slabs and slices are considered to be “live edge” styles of furniture, although we usually think more of slabs, when we use that term. So what’s the difference between the two? A slab is cut like cutting a board, along the length of the tree trunk or branch, providing a surface with the long grain showing. A slice is cut across the trunk, perpendicular to the grain and allows us to see all the growth rings of the tree.

There’s also something that would fall more into a crossover realm, where the log is cut at an angle on the sawmill. This provides an oval shaped live edge slab, which shows a pattern that’s half long grain and half rings. But finding such slabs, if you don’t have the capability of cutting them yourself, is extremely difficult.

For the purpose of this article, we’re talking about slices, not slabs, even though working with the two is very similar. But the results can be drastically different, just as the difference between a normal butcher block cutting board and an end grain one provide extremely different results.

Getting a Slice

The first step in making a tee slice table is finding an appropriate slice. That may be harder than expected. I can find a lot of small tree slices available for sale online; but not many large slices. Searching for “large tree slice” results in finding a lot of tree slices that are 12” to 16” across, with only a few that are over 24.” Those smaller ones might work for an end table, but aren’t really big enough for a coffee table. Because of their rarity, one can expect to pay a steep price for one that is big enough to be used for a coffee table.

Another option available to any of us who owns a chain saw is to cut one from a dead tree or one that needs to be removed. Once again, rarity is an issue, as not many people have trees with trunks bigger than 24” in their yard and those that do, probably don’t want them cut down. Nevertheless, I have a dead mesquite with that big trunk in the backyard of the house I just bought and my mother-in-law has a trunk from some sort of tree that’s 30” in diameter (the branches were all cut off when it died) in her yard.

Keep in mind that just cutting down a tree that big is going to be a challenge. Most of us don’t have chainsaws with a long enough bar to cut down that big a tree and buying one would be expensive, as we’re talking about a commercial saw here. Nevertheless, the possibility is not something to be dismissed out of hand.

The other problem in cutting that big a log is weight. wood varies considerably in weight, due to the density of the wood itself. Pine, which is actually fairly light, weighs in at 45 pounds per cubic foot. Based on that, the stump in my mother-in-law’s front yard would weigh in at a minimum 1,764 pounds. Considering that it’s not pine, it would probably weigh a whole lot more. Once cut down, it would take a small crane to load it onto a trailer and bring it home to my workshop.

Nevertheless, it is possible. Just don’t expect to do it on the cheap. Perhaps that has something to do with why large slabs and slices cost so much.

The good part is that cutting a slice really isn’t all that hard, for someone who is even reasonably skilled with a chainsaw. The only difficult part is making two cuts that are exactly parallel to each other. That potential problem can be solved by investing about $200 in a sawmill attachment for a chainsaw. Used in conjunction with two straight edges for rails, this attachment makes it possible to use any chainsaw as a sawmill, turning logs into boards.

Drying the Slice

One thing to keep in mind when cutting the slice is thickness. While a really thick table top might look nice, it will be heavy, making it difficult when it comes time to move. But the more serious problem with that thick table top is that it will take a long time for the wood to dry to the point where it can be used.

By and large, green wood needs one year of drying time for every inch of thickness, assuming it is not kiln dried. That should be lessened somewhat on a wood slice, as there will be more exposed end grain, which will facilitate moisture wicking out of the wood. Check the moisture content with a wood moisture content meter and don’t make the table until the moisture level reaches 6% to 9%, with the higher moisture content reserved for areas with a high atmospheric humidity level.

Drying time can be reduced considerably by kiln drying the wood slice. A temperature of about 120°F is needed for kiln drying. In some parts of the country, this can be accomplished by nothing more than leaving the wood in the garage or garden shed. In others, adding a space heater to the area where the wood is stored is sufficient to kiln dry the wood.

Wood being dried needs to be stacked with spacer strips between and under each layer of wood, spread every 16 inches. Spacers can be ripped from scrap wood and can be ½” to 1” thick. Furring strips can also be used. The top board should have spacers laid on it and be covered by a sheet of plywood. weight down the plywood with cinder blocks or something else heavy, so as to prevent the top layer of wood from warping. The lower levels will be kept from warping by the weight of the stack.

Turning the Slice into a Tabletop

Once the wood slice is properly dried, it is ready to be made into a table. It is highly likely that the wood will have split during drying, unless the heart of the log was rotted out. Cracking, or as it is known in the lumber industry, “checks” occur due to the wood drying unevenly. This can be reduced somewhat on boards by sealing the end grain, but this can’t be done on a slice. About the only thing that can be done is to cut out the pith in the center of the log. But that is only a possibility if it fits in with the table’s design.

It is necessary to decide whether the bark will be left on the slice or not. With many species, the bark separates from the sapwood/firewood/best-paint during drying. If this is the case, the ensuing space can be filled with tinted epoxy, if the woodworker’s desire is to preserve the bark. But in most cases, the bark is removed, allowing the sapwood’s surface to become the live edge for the table. If that is the intent from the beginning, it will facilitate drying to remove the bark beforehand; but the bark will probably be easier to remove after drying.

Cracks can be dealt with in one of two ways: either by installing a bow tie wood joint or by filling the crack with colored epoxy. Both are common in the style of furniture that is made from wood slabs and slices.

Before patching the crack, the wood slab needs to be machined to the finish thickness, unless the cracking is so bad that the wood won’t stay together to work it. In that case, the cracks should probably be filled with wood epoxy, as I will discuss below.

Few woodworkers have a plane or belt sander wide enough to fit a slice through. Even if we did, running a slice of wood or any end grain of wood through a planer is a guaranteed way to end up with some chipping on the downstream side of the feed. It is better to use a router to plane the wood surface, leveling it and roughly smoothing it.

To use a router for planing wood slices and slabs, a planing bit is chucked up in the router. These come in a variety of sizes, from roughly an inch in diameter to three inches. Keep in mind that this bit will have more contact with the wood than most shaping bits, so a high-horsepower router (3HP or more) is recommended, especially with the larger bits.

To allow the router to plane the wood evenly, some sort of guide is needed. This consists of a bridge for the router to ride on, which in turn rides on rails on either side of the slice being cut.

The diagram below shows the basic construction of such a guide, without the longitudinal rails. It consists of a custom router base plate, along with something to support the router a fixed distance above the bench top, while allowing the router to travel back and forth. If available, the router base-plate should be made of ½” thick polyethylene, as this particular plastic resists friction well. If polyethylene is not available, the router plate and rails should be waxed to reduce friction. In either case, the router base plate should be slightly (1/16” to 1/8”) narrower than the space between the rails.

The actual dimensions are not all that critical, although it is necessary that the overall length be longer than the diameter of the slice to be planed. The spacing of these transverse rails must be at least far enough apart to allow for the planer bit to fit between them, without it cutting the rails themselves. As for the vertical leg of the “L” making up the rails, it need only be high enough to guide the router base plate, although having it somewhat higher adds stiffness to the jig, helping ensure a perfectly flat surface after planning.

router-planer, router plate, router x rails, rail joiner
Router-planer guide

One thing that is not obvious from the diagram above is that the rail joiner/space has a dado cut perpendicular to the length of the jig. This is to allow the whole thing to ride on the longitudinal rails. Therefore, this dado must be cut to fit the thickness of the longitudinal rails.

The other part that is needed is the longitudinal rails themselves. These can be made of 1”x 4”s or steel angle. The only requirement is that they be straight and of the same size, without warp, curve or twist. Two spacer blocks, of equal length and a couple of long F-clamps are needed to hold the longitudinal rails in place.

longitudinal rails, spacer blocks
Longitudinal rails

Spacer blocks can be made of whatever scrap is available. I like to use pieces of 2”x 4”s and I typically use 1”x 4”s for the longitudinal rails. As with the router base plate and the transverse rails, these rails and the dado in the rail joiner/splice need to be waxed to cut down on friction and make the jig easier to work with.

It is possible that a lot of material will have to be removed in the process of leveling and flattening the slice. It all depends on how neatly the slice was cut. Regardless, never try to cut more than 1/8” of material thickness on a pass. Too much will bog down the router and increase the chances of causing the bit to cause some sort of divot in the surface of the material. Better to take whatever tie is necessary to guarantee a flat, smooth surface.

Don’t forget that it will be necessary to plane both sides of the slice. Start with whichever side is going to be the bottom side of the table and then flip the slice over, smoothing and leveling the top side.

Once the slice is fully planed, it will still need to be sanded to remove the tooling marks from planning. Start with a coarse sandpaper and a random orbital sander, and work through the grits, until a very fine, smooth finish is reached. It isn’t necessary to get such a smooth finish on the bottom side, but it should at least be sanded with coarse sandpaper. Please note that if the cracks are to be filled with epoxy, that should be done after planning, but before sanding.

Dealing with Splits

I mentioned earlier that there are two ways of dealing with the cracks that form during drying. One is to fill the cracks with epoxy and the other is to use a bow tie joint. For the inexperienced woodworker, it is easier to use epoxy.

Filling Cracks with Tinted Epoxy

To fill cracks with epoxy, it is necessary to turn the wood slice into a mold for the colored epoxy. This is most easily done by using a sheet of polyethylene, set on the workbench top and gluing the machined slice to it, by gluing all around the edge with a glue gun. Be sure not to leave any gaps, as those will allow the epoxy to seep out.

The exterior ends of the cracks need to be sealed with a glue gun in the same way, providing a dam to hold the epoxy in. For larger cracks, a strip of polyethylene can be used to bridge over the crack, holding it in place and sealing around the edge with hot melt glue. If there are only one or two cracks, it can be useful to make a dam out of hot melt glue around the cracks, so that epoxy isn’t wasted across the surface of the wood slice.

Once the mold is complete, “calculate” the amount of epoxy needed by filling the gaps with uncooked rice. Pour the rice back out (this may require an assistant) and measure it in a large measuring cup. Take care to ensure that no stray grains of rice stay behind. This will tell you how much epoxy to mix up. Mix slightly more, just in case.

Tinting epoxy is done with tinted mica. Vibrant colors are available. It really doesn’t take much of the mica to give a beautiful tint to the epoxy. Mix it thoroughly to ensure that it is throughout the epoxy before pouring. Please note that very thorough mixing is required. Then pour it into the cracks and allow sufficient time to cure.

Once the epoxy is cured, it is fairly easy to peel off the polyethylene and hot melt glue used as a mold. Then plane both sides of the tabletop again, to get through the unevenness and staining caused by the epoxy. Sand and finish.

Bow Tie Splice

Making a bow tie splice is a bit more complicated, but looks very attractive. For larger splits, several bow ties of various sizes can be used, with the larger bow tie on the wider part of the crack.

Start by cutting a block of contrasting wood to the bow tie profile on either a table saw or band saw. Most woodworkers make these as thick as they can, then resaw them on the band saw to turn the block into several bow ties. Roughly sand the cut surfaces.

Using the bow tie as a template, mark the area that it will occupy on the tabletop. Then use a mallet and chisel to cut out the material, making a mortise for the bow tie to set into. Take care not to make it overly deep. With the mortise cut, the bow tie can be glued in place. Trim off any material that stands proud from the tabletop surface; then finish sanding the entire surface.

When the Tree is Hollow

A hollow tree offers an excellent opportunity to create a “lake” table. This is made much like any other tree slice table, except that the hollow part inside the slice is filled with epoxy, forming a lake, much like “river” tabletops are made.

When cutting a slab for a lake tabletop, it is a good idea to cut it a bit thicker than otherwise. This allows the opportunity to amplify the lake effect by using translucent blue tinted epoxy to fill the opening. Small pebbles and even shells can be placed in the bottom of the mold, augmenting the effect.

Finishing the Tabletop

A wood slice table top can be finished with any of the conventional finishes used in woodworking. But the best finish is usually a poured over epoxy finish, as that provides a deep finish that will bring out the rings in the wood. Since the tabletop is end grain, expect it to soak up a lot more finish than normal. Even with a pour over, it may take more than one coat to arrive at the desired results.

If more than one coat of finish is used, be sure to sand lightly with medium grip sandpaper between coats. This will eliminate any bumps made by sawdust getting into the finish, as well as providing a surface that allows the second coat of finish to get a good “bite” onto the surface of the first, helping it to adhere well.

What about Legs?

For some reason, most people use metal legs on a tree slice or tree slab table. These are readily available from a number of retailers, both online and in the big box stores. It is also possible to use commercially manufactured wood legs in the table. Some styles of these can be found at the local home improvement center, but a much wider selection is available online.

Depending on the style desired pieces of driftwood, attached together in what appears to be a random way can make for a very attractive table base. The only tricky thing is attaching them together in such a way that they will have the necessary strength, without making the attachment or hardware visible. One of the easiest ways to do this is to drill through the pieces of driftwood and stack them on pieces of threaded rod that goes all the way though. The rod won’t be visible, as the attachment points are at the bottom, where it is hidden by the floor and the top, where it is hidden by the table top.

One key in doing this is to use at least three pieces of threaded rod, making a rough triangle out of them. As long as the triangle isn’t exactly even and the pieces aren’t only laid from one rod to another, it will not be obvious that the rods form a triangle.

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