Common Issues With Live Edge Slabs
Woodworking with large live edge slabs can result in beautiful furniture pieces, assuming nothing goes wrong. In this blog, we’re going to breakdown the most common issues we see with live edge slabs.
#1 – The Slab Warping
This is by far the most common issue we hear with live edge slabs. This can happen for a number of reasons. Those reasons include:
- The slab wasn’t dried right in the first place. Though not super common, it is worth mentioning. If a slab isn’t dried enough it will warp as it dries out more once it’s in a home.
- The slab wasn’t finished and it was stored laying flat or with uneven exposure to each side. If a slab, for example, is sitting flat on a floor, then moisture can absorb or escape from the top. This change in moisture unevenly on the slab would cause the wood to warp.
- Applying a finish on one side only or unevenly. If one side traps moisture and one side absorbs it, expect warping to occur. If you’re working in a garage or woodshop, and you only finish one side, slabs can warp as quickly as overnight. To avoid this, cover the one side you didn’t finish with blankets and finish the project as quickly as you can.
- The slab wasn’t stored in a good location. Locations such as bathrooms or basements that have high moisture levels in the air are not ideal. Garages or storage units are also not ideal unless they’re heated and have dehumidifiers.
- The slab was transported with stress on the wood. For example, if you transport a 12′ slab on a truck with a 6′ bed, good chance it can warp by the time you get it home.
- The slab was left outside and it rained or was exposed to high temperatures and sunlight. This can cause warping within hours.
How to avoid warping:
Warping is usually avoidable. The best things you can do to keep your slab from warping are:
- Store it upright after it’s flattened, not laying down.
- Store the slab wherever it’s going to be used as a table for 1-2 weeks before finishing it. The slab will adjust to the moisture content of the location it’s going. Changes in moisture content are what cause the slabs to warp the first place.
- Check the moisture content before buying. If you’re in PA or Maryland, we recommend slabs that are dried to 12% or less throughout. If they are not, store them in your house as recommended above before finishing.
- Cover them with moving blankets and support the entire slab evenly when transporting them.
- Keep your table away from areas of high heat such as floor vents and other heaters such as wood burners.
- Don’t use live edge in areas such as cabins unless they are temperature controlled year-round.
- Mount the slab to a base. Don’t just sit it on one – actually mount it.
What if the slab already warped?
If the slab already warped, there is a good chance it’s still a chance it’s not ruined. When this happens, you can flip the slab over and often it will take back it’s original shape within a few days. If it doesn’t, you may need to flatten it again.
#2 – The Slab Cracking
The second most common issue is a slab cracking. This can also usually be attributed to changes in humidity and temperature. This typically happens at the kiln or while the slab is air drying. However, it can happen once a table is mounted to a base.
A fact with all wood is that it moves. It expands and contracts in different environments. If your slab is mounted in a way that doesn’t allow for the wood to expand and contract like it wants to, there’s a high probability that it will crack.
A few tips to avoid cracking
There are a few things you can do to help keep your slab from cracking:
- If you’re using a metal base, be sure it has slotted mounting holes, not round ones. When the mounting holes are slotted with across the grain of the wood, it’ll allow the wood to naturally expand and contract. If the wood can’t move, it will crack.
- Use threaded inserts to mount your legs. Be sure these are perfectly centered on the leg slots.
- If mounting to a wood base, choose a mount that allows for wood movement across the grain.
- DO NOT mount using screws. Screws can typically be used for very small pieces, but you will likely run into issues if you use screws to mount larger tabletops.
Bonus tip for avoiding cracking and warping:
Cutting the slab down the middle and using domino joints and wood glue to put it back together can remove the stress on the pith of the wood. This can help to alleviate many of the common issues.
You can also use multiple slabs on your top, which is known as a bookmatch. Bookmatching is a great tactic for making a live edge table with any size and shape. This also makes the wood more structurally sound than buying a large slab for your top, which is why it’s often preferred. Rip cuts with the grain of the slab relieve tension and decrease the probability of your slab warping.
#3 – Soft Spots & Holes in the Wood
Soft spots can often appear in wood in areas of rot or where there are bug trails. If you’re wood has little powerdery holes, there’s a good chance it’s a powderpost beetle. Often these trails are right below a thin layer of wood, and can lead to a weak spot. They’re typically toward the edges of the slab.
If this is an issue, there is a few things we recommend. For large holes, you’ll want to fill them with epoxy resin. Once it cures, the epoxy will strengthen the wood. For smaller voids, we sometimes use starbond, which is an adhesive designed to fill voids and cracks on wood.
Whichever route is easiest is better than doing nothing. Tabletops are often areas of high wear and tear, which is why we recommend filling any voids in the top of the piece.
Soft spots may also appear from rot. If this is the case, oftentimes it’s best to remove the rot and fill the void with epoxy resin. These fills the rotted area and forms to the shape of the void, making it a great way to solidify a tabletop.
Questions About Common Slab Issues?
The issues mentioned in this post are extremely common for even experienced woodworkers. If you have any questions before purchasing a slab, please drop them in the comments below or ask before you pickup you wood slab!
I have question on properly mounting legs to a live edge table. I know you say to make sure they are slotted and to use thread inserts. Do you actually leave the screws slightly loose when you mount the legs to allow movement?
Also, I thought I read in the above comments something about not using screws to mount the legs?? Could you explain? Thanks
We typically use threaded inserts for mounting the legs. We tighten them snug, but no need to overtighten them!
My brother is wanting me to build a door with solid wood with an epoxy fill, like done in river tables. My question is, how do I keep solid wood from warping? I have channels that i could install, but would this be enough? Your input would be greatly appreciated.
It would all be in buying lumber that’s properly dried for the environment it’s going to be in. I’d recommend buying from a local lumber store that dries it’s lumber to the moisture levels needed for where you’re located.
Hello, I have a bench made from red oak, kiln dried live edge. I finished with teak oil and sparz urethane. My problem after one year is some discoloration in a few spots; grey/silver tone (almost metallic). Any idea what would cause this?
Sorry we don’t know what would cause this as we rarely use those finishes at Lancaster Live Edge.
hi there. We have built a Smoke, BBq shack and just recently bought a live Hickory slab to make a bar top. we have had it in our garage(not heated) and just noticed a huge warping, bowing or cupping not sure which it is. How do we get this flat again so we can start our process of finishing it to use for our outdoor bar top.
Hi Cindy,
It should adjust to your garage with time. I would recommmend planing it down and finishing it with a highly water resistant finish like polyurethane. This takes a good bit of work, but is the best long term solution.
Hi, I just ripped a few slabs of cedar and doug fir and was thinking of make some benches. I do not have access to a kiln and the wood is not dry. can I Poly the benches completely before they are dried? Will they hold their shape once the poly is dry, or will they warp over time. I made some sycamore trivets using 2″think rounds and applied poly to seal the wood while it was still wet and they have not cracked or warped at all, it has been about 6 months. I’m wondering if I can get away with that method for the benches?
Thanks
They will almost certainly warp if they’re freshly cut. I would definitely recommend air drying at a minimum. Wood, especially when cut in cut in widths over a few inches, is almost certain to move regardless of the finish, especially when it’s not dried. For live edge, where most is 12″+ kiln drying I would consider an absolute must.
Just want to say thank you for the excellent technical advice.
You’re welcome. Glad it was of value!
I have a black walnut slab 78” x 16” x 1-3/4”. Side to side it is very good but lengthwise it has a gentle belly of about 1/2” in the center. My thought was to make relief cuts in the center and install two c-channels lengthwise to try and slowly remove the belly by tightening the c-channels. Thoughts?
You can often get them flattened which is what we would do in this scenario! Then the c-channels are some extra support to prevent future movement as much as possible!
So I have 4 slabs of honey locust kiln dried 3 out of the 4 have a good amount of rot/bug holes which add a lot of chars to the pieces, just curious on how much or all of it do I need to take out to make the table not have weak points.
Hi Eli,
Have you considered soaking in epoxy to fill these holes? It’s a great way to sturdy up a slab with some weak points in it. The epoxy is honestly more solid than the wood in many cases and the bonds hold amazing for this type of application.
I’m making cutting boards and live Edge charcuterie board
I’m having a hard time with the live Edge charcuterie boards I get them flat but no matter how many times I put them through the planer there is I very small about of wobble when checking the corners.
Any advice?
Should the charcuterie board be 100% level?
We don’t do a ton of smaller pieces anymore, but when we did, we would flatten the entire slab vs little pieces. It’s hard to tell what the issue may be as we have commercial equipment for this, which is a bit easier than a bench planer or small jointer.
Hi there gurus of wood. I have put together a cypress pine live edge table (approx 4 X 3 ft mounted on steel frame) for my son. It is made up of 2 slabs from same piece. Gap in middle is approx 1/2 inch. I filled with carbon body filler. It is outdoors under cover (Melbourne, Australia). Of course it opened up on one side of filled edge. Now I am wondering if I drill some small holes underneath would this take up moisture build up. Weather is ever changing here and I am going to refill opened crack while it has dried out but no sure what will happen with moisture build up. Any advice grately appreciated.
Hi Philippa, Unfortunately I don’t know how much we can help here given we rarely work with softwoods. What I can input is that we never recommend larege slabs like this for outdoor applications as they typically will always warp or crack due to changes in the humidity, temperature, etc.
Hello there, I recently stripped the bark off, nylon wheeled and sanded the edges of several live edge red cedar slabs but noticed that some pieces have a vivid yellowing on the edge that won’t go away with sanding. Is the yellowing from resin? And how can I get the yellow out?
Thanks
Hi Raianne,
Unfortunately we don’t work with cedar much so I can’t speak much to this. I’ll leave the comments open here in case any other readers have ideas. My gut says you may be right on the cause for this.
We have a large coffee table with a slab of some kind of South American wood, 21/2′ x 5′ x 8″. How do we fill a large crack, 1″ wide at the edge, reducing to the end of the 3′ crack, and 4″ deep at the table’s edge? We would like to put turquoise pieces along the top of the crack. Thank you, Jane Wulsin
Some deep pour epoxy should do the trick for this! And you can buy different coloring as well to stir into the epoxy. Everything you’d need should be available on amazon!
Hey there!
I am a woodblock print maker and am working on an old slab of bishop pine. It was heavily oxidized an lying around in a friends shop for I don’t know how long. After a pass through a planer the slab cleaned up and has been perfectly flat. I have been carving it for the last couple weeks and made the mindless mistake of leaving it leaned up over a heater at a friends (didn’t realize the vent was there). The slab bowed and I immediately applied damp rags to the side exposed to the heat. It began to flatten and then started to bow completely in the other direction. It hasn’t seemed to stabilize at all since (about 12 hrs). I know have it lying flat with moist side exposed hoping it will dry out. My intuition is to leave it alone and stop intervening…but curious what you would recommend. I am desperate as the piece is for a show in a couple weeks and I still have some work to do on it. Thank you!
If it’s moving this much I’d definitely leave as is for a bit. It seems like it may be green lumber you’re working with if it is moving this much.
made some live edge serving trays out of 1in thick walnut. roughly 8x25in. moisture content was 9%. put odies oil on it as a finish, but faces, edges and ends. now the next day it’s starting to cup. what do you think the issue is? thank you
Most likely the slab has a higher moisture content by a good bit than the room/home it’s in. In this case, you’d be best to flatten down again and refinish it if it’s very bad.
hi there, i bought some fresh iron bark slabs for a table top that were not fully dry and laterly i have been working with them and we are having trouble with them starting to walp every since we have been working with these cutting them down to size so they are able to join, was just wondering what the best oppurtunty would be to stop these from walping.
Hi Tom,
I would recommend letting them dry fully prior to doing any work on them. We do not work with anything unless it’s kiln dried under any scenario – otherwise, the piece will likely warp or crack (or both) within days of being in a home.
I am getting a live edge table made of malabar chestnut (80″ X 36″), and am in the process of choosing the slab. The slab that I liked has a crack right across the middle of the edge that is the width of the table. I cannot quite tell how deep is the crack (perhaps a couple of millimeters). Is this a non-issue or should I look for another slab. Thank you, Abha
Slabs do often crack when drying. It’s not too big of an issue and can be fixed with epoxy!
We just moved to VA with a 9’x5’ rain tree live edge stunning table. Two months in a new home and a seasonal change has caused cracks for the first time. We’ve only had the table for about 4 months. Humidity in that room is around 30%. Would putting a humidifier in there help? The cracks are mostly on the underneath and a few small ones on the side. I will do anything to try and save this expensive, beautiful table!
One thing you could always try is just leaving it as is until it reaches the moisture level of the home, which could be in a few months to be safe.
Then, you could always pour epoxy in the crack, sand it down, and refinish it. It sounds like the damage is already done so this is likely the only option I can think of!
I’m making a river table out of yellow birch but want darker finish, what type of finish should I use on the top? also what type of wood do you use for frame before epoxy to prevent it from sticking?
I guess it depends on personal preference. I don’t have a recommendation on stain as we rarely do anything other than natural finishes on our tables. However, for the epoxy frame, we just use tyvek tape over 1x4s to keep them from sticking to the epoxy!
I just took delivery of a walnut live-edge table from you guys which is beautiful—and I want to make sure it stays that way! I live now in the high-altitude Nevada desert (which is very dry year-round), so as I am a transplant from the (humid) east coast learning to care for wood here has been a bit of challenge. Could you recommend a regimen for oiling/waxing the table to prevent warping and cracking, especially as it gets adjusted to the new climate?
Hi Sarah! Sorry for the delayed response on this. If it hasn’t warped in the first few months, you’ll likely be fine on this. If it has, you are likely best to flatten it, sand, and refinish it once it’s fully acclimated to the environment it’s in.
Hi there I just picked up my newly finished epoxy/walnut table after 4 months so it’s had plenty of time to dry in his shop. The man who created it for me knows I was going to store it flat on a carpeted floor. Since I was just reading your article I noticed you recommend to store it upright . I myself have worked with wood and know all about warping and how to fix it but I want to be extra careful with this table because I’ve never used walnut. He’s done an amazing job so I don’t see any signs of it ever cracking for any reason. I would never store it in a garage but do you think that leaving it standing straight against a wall and just left in wrap would be ok? I don’t have the leg base for it yet because I don’t have the room for it at the moment which is why I’m storing it. Appreciate your feedback…thanks
Hi Caroline!
If the wood is dried to the appropriate moisture content of the room it’s stored in, you should be fine here!
I have a piece of live edge maple without the bark- it has a white dried 8 inch section along the live edge -maybe coming from a knot in the wood but not sure-would this be sap and if so what should I do about it when I go to finish it. It’s not sticky .
I am not sure what this would be. Hardwoods like maple wouldn’t have sap so it wouldn’t be that.
Hi, I have a live edge honey locust slab that was cut from a tree that had been dead for 12 years. I’m making a desk from it, and we’ve been filling the cracks with black stained Bondo because the live edge has cracks that I didn’t want to fill and I figured epoxy applied on the faces would leak out the sides. After filling about half of the cracks with black Bondo and wood filler, and leaving it for a week, we went in to fill the rest today and the cracks have grown considerably. Should I just fill the whole thing with epoxy, or should I laquer the whole thing prematurely to lock in the moisture, or should I use some bowties then continue using bondo? What can be done to save this slab?
If the wood split that much more in a week, its not dry enough to be working with yet. It’s going to continue to split until it reaches a sustainable moisture level for the room it’s in. I recommend kiln drying it to the moisture level of the room it’s going to be put in before doing anything else.
I have a black walnut live edge walnut table, has two seams. After having in my house for 3 months I am having some movement at the seams which has cracked the oil based polyurethane. Is there anything I can do to fix it or will it keep happening?
Hi Darrin, it could keep happening, though the cracks likely removed the stress on the wood already. They really can only grow at that point.
If it gets too bad, the only real option is to flatten the slab and refinish it entirely. If the wood isn’t dry enough when something is built, it’s basically the equivalent of a nice house on a bad foundation.
Is there a recommended matte finish for a live edge dining room table with resin fill?
We use LED hardwax oil since it cures quickly, but the light to cure the finish is very expensive. Odie’s Oil is a great finish for a slab as well. It has a very similar look, it’s easy to apply and affordable. You can pick it up on Amazon. For extra durability with Odie’s Oil, you can apply the oil followed by the wax.
Is ash a good wood to use as a live edge table top?
Absolutely! If it’s not rotted in the center (which a lot of the times it is) Ash is a beautiful wood. We do several pieces out of it. Even if it is rotted, you can always fill those voids with epoxy resin!
Hey guys! So I have an issue with eight oak slabs I milled from a customers beloved downed tree. They want live edge tables with epoxy rivers + benches, and two sliding barn doors. From whgat I understood, the tree was lying on the ground for almost a year (CA). I milled them into 2 1/4″ slabs and a bunch of 1×6 and put them in my 8’x16’x8′ home made drying kiln that’s attached to my shop. I ran fans and a really small dehumidifier for 6 months. I flipped everything a few times and always stickered etc.. I tested them and got measurements ranging from 50% to 10% and jumped up and down the scale depending where you placed the meter. A week later we were evacuated from our property for two months (Caldore Fire) where they were left in the kiln with both front and rear doors wide open where they received a constant flow of air. When i returned to the beautiful site of my shop and home still standing (It is a miracle the firefighters were able to stop it feet from the house. We learned two companies had a tremendous 14hr firefight overnight into the next day fighting to save ours and our other 5 neighbors homes! Incredible!) So when I returned they had lost a lot more moisture but I still have these readings that vary anywhere from 6% to 20% to 35%, some tiny areas read 53% . The majority of the slabs are about 10%-12%. Why are they areas with totally different levels and can I build with them like this?
This is pretty common. Sometimes you can get pockets of moisture. Moisture also leaves some areas easier than others. Straight grain vs figured dries very differently. Drying wood is certainly an art, it may be worth checking with a local lumber store that has a professional kiln to see if they can dry these the rest of the way for you.
Have a large redwood slab 4×12′ and 4 inch thick.
Its raised in the middle about an inch. Cupping and twist not really issue.
Its probably had 3 years of drying. Last winter it was out on a covered deck with about 300 pounds on middle. Didnt seem to straighten.
Thinking my next step is to kerf concave side half way down perpendicular to length. I thin i just put a wedge in kerf. Calculated i need to expand on 0.007 inches on each side. Eight kerfs would be enough i would think. Or kerf convex side and use epoxy with high shrinkage to pull it flat.
What would be your strategy? Really cut in half would be the thing but i rather not.
This slab will be in a cabin without climate control so looking for solution but not expection perfection.
Hi there,
I would track down someone in your area with a slab flattener. You’ll lose thickness, but it’ll be the best bet. You could also build one out of a router and homemade sled, though it may take a while to use on a slab this large!
I second what Lancaster Live Edge said about building a router sled and flattening it like that. You will lose some thickness but you can make it straight as an arrow. All you need is a metal bed frame made with Angle Iron and measure the with of your Router’s base plate. Then cut 2 scrap pieces of 3/4″ plywood to the same width as your base plate + 1/8″ so the router can move freely between the rails. Secure the plywood pieces at the ends of your sled with metal screws or drill holes and use bolts and washers. Then just get yourself like a 2″ planer bit for your router and go to town on it until you get it to the point where you are happy with it.
Have a redwood slab , making into table. Waiting 3 more weeks for legs. It is outside on sawhorses.
It is sunny during day so I leave it open, what should I cover it at night with so condensation doesn’t drip on it. Plastic?? Your answer would be much appreciated.
Jeff
Hi Jeff,
We normally wrap ours in moving blankets, but definitely recommend keeping indoors overnight since the moisture levels can change so much!
I’ve noticed wood dust under my live edge living room coffee table. Can something be living in it
If it wasn’t dried, that could happen. Kiln drying kills all of the bugs in the wood, so if it wasn’t then that is a possibility.
Just purchased a very expensive live edge walnut dining table. Picture sent to me did not reveal
the crack in the table. The selller told me as the artist he liked it and it was common to have cracks.. jThis one is the width of a pencil and 17 inches long. I was told it could be filled with epoxy. He showed us a picture of one with a “river” through it that he made for his mother. Since I started my research – apparently too late, there is a picture on line that looks very similar for 1/4 the price.
Please advise
Not sure we can speak for someone else’s build – but it isn’t uncommon for large slabs to split or warp even if they’re dried. It’s happened to us in the past.
Natural wood, especially wider slabs, need to move a lot more with changes in humidity levels in the air. The issue could be that the slab was dried for one environment, then stored in another. It could also be how the legs were mounted or that it wasn’t completely dried.
The best method to avoid this is cutting the slabs into smaller pieces, flipping the grain on every other piece, then gluing the slabs back together. Otherwise – any table can warp or crack, even if all else is done right.
Sorry to hear about your table. Our recommendations would be the same – fill the crack with epoxy, refinish the piece, and it should be good to go.