The problem with Air dried lumber... Don't let this happen to you.

In this video I go over a table i made where i used air dried barn wood and had issues because it was not properly dried for its purpose. This is why i will be using kiln dried lumber moving forward
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bradyhommel...
www.bradyhommel.com

[@andygorski6318]

Air Dried (AD) and Kiln Dried (KD) will move the same amount if both are starting at the same Moisture Content (MC). If the normal summer MC is 11%. Since your AD lumber was "50 years old" and was properly stored, it should have been at the normal summer MC for your area. And if you bought KD lumber that was dried to 8% and brought into the same environment as the AD the KD lumber would gain moisture until it reached 11%. Based on a chart that I have the Jan. MC of interior wood is ~6% and the July MC of interior wood is 11-10% in the Up State New York. If the table is Red Oak and is 36" wide, and pinned (glued) in the middle of the bread board. I would expect each edge to moved 18"[0.00338(6 - 11)] ~= .3042 or roughly 5/16" from Jan to July (expand) and then July to Jan (contract) (It could be more, this is a ball park). This movement would easily be seen because of the bread board ends. So what happened here? Normal seasonal wood movement was not taking into account. Since the table was constructed in July (peak expansion) the edge of the table should have been proud of the breadboard end by 1/2 of what the expected total wood movement will be from Jan-July. (Based on the table shown in the winter I'm assuming the edge and breadboard end were flush in July when constructed). So that top is now proud of the breadboard end in the summer, under in the winter, and flush twice a year (spring and fall). Also need to make sure the unglued tenons have the proper amount clearance to move freely.. The calculation is an estimate. It could have been unusually humid when the table was constructed so MC could have been 12 or 13%.. The top could be wider the 36" which would also increase the movement. The calculation is based of a formula (13-3) on page 13-16 of the Wood Handbook: Wood as an engineering material by the US Forest Service

[@kylecorry9537]

I came here to make sure someone pointed this out. Wood moves. You have to account for it. And kiln dried lumber will go up. Everything wants to reach ECM for its environment.

[@terrapinjonathan.]

Very well stated

[@levilam522]

The larger the individual pieces the more it moves...

[@integr8er66]

Fantastic write up. Thx

[@SKANK_HUNT49]

What he said

[@oldrudedog]

Lesson my wood shop teacher taught me 65 years ago, is that wood will take on what ever ambient moisture that's it's in. Doesn't t matter how long it's been air dried, it will still pick up what ever moisture it's in. Did you finish the underside of the table. That's where most wood workers fail. My teacher told me to finish all surface., because what is not finished will absorb moisture and the finish surface will not. That's why a lot of furniture warps and cracks over time.

[@dtg3784]

The table looks great, I think this is more about managing customers, expectations and conveying to them that this is a piece of furniture that will interact with this environment. It will react to the humidity of the seasons. It will contract, and then it will expand back to the original size. They have to realize this table top is not a piece of plastic. The beauty of natural wood comes with some caveats. Again, beautiful table.

[@ninjapancakes9435]

Been cutting down trees for people and decided to get a small mill. Now I got all this wood and don't know what I'm supposed to do with it to get it usable. This was helpful thanks for sharing!

[@LukeLong-oi4uc]

Just found your channel. Great content. I’m actually dealing with a similar problem. Bought a walnut coffee table and end tables. The guy I bought them from actually milled up the logs into slabs himself. The end tables are fine, but the 1 3/4” top on my coffee table cupped after the heater in my house pulled the moisture out of it. I’m going to have to take it off and rip it at the center seam, and then run it through my planer. I might actually have to make 3 cuts and plane down 4 pieces instead of 2 so I don’t lose very much thickness. The fella who built it apparently doesn’t know how to cure wood properly before building with it. I didn’t say a word about it to him, he did me really good on the original sell, he’s a great guy. I just chalked it up as a lesson learned on my part. lol I really appreciate you sharing your experience with us. Can’t wait to watch more of your videos! Blessings! P.s. that is a gorgeous table top in your video. You’re very talented! Nice work!!

[@jacobsimpson347]

Get a moisture meter and ask customers what their inside humidity is at during winter and summer months. That'll tell you what moisture content the wood should be at before building

[@hosoiarchives4858]

Would you mind explaining more?

[@mustbsavdbyjesus]

Moisture content and relative humidity are not a linear match from what I understand. MC of between 6 & 8% correspond with about 35% relative humidity

[@andrewupson2987]

​@hosoiarchives4858 if you know the typical temperature and humidity of the space the furniture will be in from summer to winter you can determine the equilibrium moisture content for both extremes. Then you can build around the EMC at your shop (or the measured MC of the wood) vs their home. So, if the wood in the video was a moisture content of 12% you'd want your breadboard ends a little shorter than the field of the table is wide. That way as it dries out during the winter the top will shrink to a normal/acceptable amount vs the breadboard end. Then when the humidity of summer hits and it swells it will also remain within acceptable amounts.

[@williamlloyd854]

I with ya. I have had a 4inch sycamore slab. It had been stuck back in my shop for 8 years. With live edge, it was 12 ft long. 43 inches at the butt and 35 at the small end. I do lots of turquoise inlay. Had a customer want this as a conference room table. The slab had a check about 20 inches, from end of check to 2 inch opening. I butterflied with ash bows, top and bottom. Since the slab was 4 nch thick, i used expanded foam to fill the majority of the check, leaving about 3/8 of depth at the top of slab. Underneath, i glued 1/4 plywood on top of the bottom bow ties. On the top, I used 2 part clear epoxy Before pouring the epoxy, I ground and sifted Sleeping Beauty mine turquoise. True stones purchased out of Arizona, not some Chinese fake. Anyway. After the top was completed, sat at the office on a frame of 3 cypress flaired stumps. Customer, attending board members, clients of the firm, all fell in love with the boardroom table. 3 months later I get a call. The check had opend even more. Large fissures had opened around the turquoise. Needless to say, air dried wood, no matter how old, when introduced to low humidity of a room with HVAC control, nature will reach up and bite u in the butt. In this lesson I learned that the humidity in a controlled environment will have a moisture content of about 9. Build accordingly

[@frattman]

Thanks for the video. I stored 600 or so square feet of oak flooring I had milled in the unfinished second story of my cape. The powder post beetles (not exactly sure, could be another species of boring beetle) will live in the wood for many years after being milled. On a quiet night you could hear them munching on the wood if you were up there. I did freak out a bit thinking they'd eat my home but as far as I can tell they will only eat the sapwood and maybe just the sapwood of hardwoods in particular. I also shuffle 3-4 cords of firewood into my house every winter and see frass buildup on the rug underneath the fire hoop indicating live bugs in there. So far my hardwood floors haven't been eaten away. I'm not saying it can't happen, but It hasn't happened in my house over the span of 8 years (that I can tell).

[@WideCutSawmill]

Also would depend on where you are air drying it. I E: Air drying in New Mexico is probably as good as a kiln minus getting hot enough to kill bugs.

[@scottconley7698]

Oh I learned this hard way as well. First big project I did was bread board table top and end tables for patio (out of sun), but in Arizona. Used 100 year old wood with the bread board ends and 2 years later it looks almost the same as yours. Needs to flattened again and trimmed back. Ugh.

[@grantgood8456]

i think you did right by the customer, however if you built the second table with a lower moisture content, what is to say it wont expand to much in the humid months? you might be getting another call if the customer does not change the home climate and make it more stable for a sensitive table design. this sounds like a painful case of the customer is wrong or may need to change expectations or understand a table like this needs a stable environment, as others have stated so well wood never actually stops moving or adjusting to humidity.

[@frankshannon3235]

One conclusion that could be drawn from this experience is that a good process might be to air dry down to what you can get, 12 or so, and then move it into a space that's climate controlled close to what it will be like in it's future home.

[@erallen97]

Great video. That rough cut lumber is always so tempting because of the price.

[@BradyHommel]

Sure is!! Just need to make sure it's dry for the application your using it for!

[@integr8er66]

So the real problem wasn't that you used air dried lumber, but that you didn't let it acclimate to the environment it was going to live in.

[@toodjackson4438]

I know everyone said that but the humidity is going to change and if you move to a different place that's going to change too

[@benchase7537]

its just more click bait

[@fandyu69]

Thank you very much! Very handy to know

[@kylehuberofs8052]

It's all about where it's going. We have a humidifier on our furnace and keep the humidity around 30% inside. My shop is heated with a Woodburner and really dries the wood out. Just about everything I build swells when it's taken inside. Just have to build everything to allow it to expand and contract. I sold a piece that was 18 hours away and had to drive all the way there and fix it on spot because it swelled over 2 inches (with kiln dried lumber)

[@BradyHommel]

Damn 18 hours! that's a bummer!

[@renderuthis]

none of the videos about drying talk about where they live and what time of the year they stack it. here it will dry, 100 outside with almost zero humidity. I think at one point over that amount of time it was dry.

[@hughdillon6166]

This is great to learn from.

[@andrewsblendorio]

Thanks for sharing man!

[@chrissartain4430]

Thanks for the Information.

[@danielscheive7619]

I just don't see any flaws not sure what their expectations were maybe try aluminum or pvc

[@johnmoyer5515]

After it comes out Of the kiln unless your storing it in a controlled environment it will rise up a few points in moisture relative humidity in your location. I worked for a small cabinet shop 50 yrs ago made lots of custom kitchens kd lumber purchased from commercial supplier lumber would be stored up in old hayloft we would bring material into shop a few days before milling it rough cut our stock& let it rest for a day or two.. I have a HM 130 also & I do want a kiln. I do historical restoration & use reclaimed lumber recently I had to replace about 20 door jambs long leaf yellow pine 130 yrs old not all but a few have to remade, Let's saw up some trees now get max together,

[@chrisristau8803]

I glued up a top for a coffee table a few years back and once i had it in the clamps i carried it out to my porch so it was out of my way... Well it was starting to get cold outside at the time and it was warm inside.... I didin't even think about it shrinking but when i went out to check how dry the glue was it had shrank so much the clamps were so lose they were falling off and all the glue joints were open.... I was so mad lol

[@johndeaux9987]

How do you like that moisture meter? How deep will it read?

[@austin2842]

I just picked up some fresh milled tamarack (larch). It's in 2x10 boards. I'm using these outdoors in a landscaping application. The guy suggested air dying 1 to 2 weeks before use.

[@arthurjackson]

That’s exactly how breadboard ends are supposed to work. I think your mistake was to make the ends too long during the wet summer. Cut them back by 1/2 the distance and it should be fine. Table tops can be difficult. I garbage picked some beautiful oak tabletops in Breckinridge CO (a hotel was just throwing them in the trash!) and then I moved to a low altitude wet area and they cupped and warped like crazy. Now I have to cut them up and plane them down. It’s still good wood though.

[@vharboe]

That top would be easily fixed. Slice off the proud ends, shape, sand and varnish. Done. Never ever use wood that is not «furniture dry», which is 6-12% moisture content. Goldilox zone around 7-9% depending on where you live in the world. Wodd that has been drying since Noah built the ark won’t be dry enough, but it would be very well seasoned. You need to dry the wood down inside a climate controlled room until the wood is around 8% or so. Then you won’t have any issues. Also, make sure you allow for movement in your design - something you did very well here with floating tenons. Which is proved by the fact that the table top did not rip itself to pieces! Slice the breadboard ends flush with the sides, and it will be a solid table top that won’t do anything crazy.

[@MADGUNSMONSTER]

Amateur woodworker here, and i suppose my plan to dry my fresh Lowe's lumber in the NY sun for 3 days is not happening.

[@joeminocchi2947]

""Be careful storing that lumber in your basement. If it hasn't been kiln dried, the bugs and whatever fungus it may contain will love your home. I dried some 2 1/2" slabs in my basement with a dehumidifier not knowing this information. Later had to debug the house. I realize you stated you're going to build a kiln in your basement but your video showed an arrangement or wood in your basement already.

[@MrMonero]

Why did you have to debug? What bugs did you get? Could understand fungus or mould maybe spreading around if you have a dehumidifier running and pumping spores and dust all around in your air. Have never heard of bugs becoming an issue though.

[@joebourgoin6554]

What kind of bugs did you get?

[@joeminocchi2947]

@@joebourgoin6554 Ants were one species and then I don’t know what the other was. It was small gnat like insect. Never had a problem with them before until after I had the wood in the basement.

[@faithzoellner]

I'm just starting out trying to do any sort of woodworking..I have some logs that have been left out all winter My question is,could I potentially torch a log with a propane tank torch to dry it out? Or would that be almost impossible It's a personal project so it doesn't have to be perfect but I would still like something that doesn't look like a mess

[@anthonybeers]

Few strokes with a jack plane and some linseed oil later I would be done fixing that table top. It already shrunk probably about as much as it is going to and it looks like your bread board ends did their job.

[@BradyHommel]

I did fix it and put it on a different base. I used for a year for our family and it was all good! I sold it not to long ago.

[@ryandavis3336]

Any update on the kiln? How was the build? How's it working now?

[@fngrusty42]

Unless they live I s. Fl. The humidity is bad here will move wood dry or not. Learned to not build bread board tables if they keep there windows open. Lol fun place

[@johnnycorn7225]

I'm after the lightest strongest option I can use for speaker boxes any suggestion/ material that doesn't distort after being sealed in and out!? Been plywood forever, but wanna do something different

[@Vandilbg]

Like others said. Would have likely been just fine if you hadn't assembled it in 100% humidity work area. Even kiln dried wood will swell if left in that sort of environment and then shrink when taken inside.

[@Bakanelli]

How was that table finished? Maybe if it were completely encapsulated with good quality polyurethane varnish I would have prevented any wood movement

[@mikecameron5322]

So is the problem building it outside during Hi humidity or is it air drying.

[@travisedwards9983]

Just using wood stored outside and then bringing it in with AC will do this. Even seen antique tables that had been stored in garages.. put inside and humidity sucked out by AC.. and they rip apart.

[@BradyHommel]

Wood has a mind of its own. Lol

[@pambelgum5790]

Can you dry black walnut slabs in the backyard with a tarp over it during rainy season? What about mold or fungus growing?

[@bhough410]

You could dry it that way, but I definitely wouldn't. Walnut is prone to bug attack if left outside.

[@shaneallison3370]

Now all you gotta do is capture some fees for the education your mistake just gave everyone 😆. I don’t know why but your presentation on that mistake had me laughing. It sucks making mistakes but hell I always say it’s way better than book learning. 🤙🏻

[@BradyHommel]

I've always been a learn by doing guy. Books were never NEVER my thing haha

[@greg2337]

The wood should be acclimated to where it's going to live its life. Air dried wood has better working properties and color. Instrument wood is often air dried and they dont have movement issues if the wood was acclimated properly. Just an improper assessment of the issue. I understand how you concluded it though.

[@trimbaker1893]

a book worth reading is "the nature of wood"

[@BigSkySeabee]

god this makes me nervous.....i have a tree that came down during a hurricane that im turning into a table ( Haringbone Pattern Table....god help me) and i already agreed to the customer that we would air dry the wood for a yr, then build......its Oak....this is gonna be interesting now that i heard what happened to you.

[@soltesznagytamas]

❤

[@zachgoestoeuro]

I’m trying to justify the price of buying allegedly air dried lumber locally, then taking it to a kiln, compared to picking it up at Home Depot. Currently hobbyist building furniture and cabinets for my home.

[@frankshannon3235]

You don't have to go to Home Depot. I'll bet there's a hardwood lumberyard nearby that stocks lots of species that are properly dried and ready for furniture. They'll surface it for you to whatever you want. Usually I just get mine straight lined.

[@walther9161]

But is a typical issue with a bread board ends like that..? Two different expansion directions.

[@tristinaugs]

What about using air dried lumber for building a shed?

[@BradyHommel]

Oh air dried is completely fine for a shed. You can use freshly cut green wood to build a shed if done correctly

[@react1200]

Are some woods more susceptible such as white oak?

[@BradyHommel]

I do believe it varies per species. I know that quarter sawn white oak in one of the most stable

[@andrewupson2987]

Quarter sawn anything is going to be fairly stable. But no matter the wood species or how it was sawn, it will move with seasonal changes. If you can't tolerate that movement, build it out of something other than wood.

[@MrThenry1988]

Ive been there.

[@BradyHommel]

I don't even do breadboard ends anymore because of this.

[@yusefmessallam]

be careful about moving non heat treated lumber in your basement, you could risk infesting your house with bugs if you get an infested tree in there.

[@waynekeeler1442]

Thanks for showing your mistake

[@codykastler4709]

The real lesson here: don't build breadboard end table tops. 👍

[@BradyHommel]

Basically. Yes! Lol. I haven't since this table and probably won't again

[@macp721]

I don't agree with this this is subjective because I have I have bought kill them dry wood all my life from the hardware store and they would shrink a wap exactly the same. I own my sawmill and I have able to gotten better lumber air dry from what I actually got from the lumber yard. I think it depends on where you get your wood what you going to use it for on the species of what somewhat dry different than others depends on the thickness like you just said in your video. Just say you get 100-year-old barn wood which is in a barn drying slow in the cold you know. Then you take that lumber and immediately cut it get it to your whatever you need for your project and then sell it The most likely going to have a defect The thing you should do you get the lumber you figure out what temperature was going to be used for you let it sit in your shop somewhere around the same temperature before you actually use it then when the lumber start to wiper do it saying now you could correct it and take all those things out because that most likely won't happen to the lumber after you get it done. And it's stuff like tables anytime you start seeing movement and the product before you do it like I said you know you could add metal to the bottom of your table you know create some grooves and then add your metal. Because your video gives sawmills a bad name and people who air dry lumber a bad name and people don't know what they're talking about customers oh I want kiln them dry kiln them dryer is not always that great

[@JayCWhiteCloud]

Hello Brady, This being an old video, I'm not sure you will see this comment, but please do respond if you (or a reader?) has questions. Just about everything you post in this video is either incomplete or massively inaccurate in many ways. I've been a traditional woodworker and Timberwright for over 40 years now and over 90% of the wood I use to build with (architecture, flooring, furniture, etc) by modern standards is all GREEN and I simply do no use "cooked wood" (aka kiln dried) in any of my work. I will hit the highlights below: 0:04 100 years is more than enough time to dry wood, and this is about knowledge and skill sets...NOT...whether the wood was dry enough as it most certainly was... 0:20 The table top was "properly dried" but in some ways was not built or finished correctly, and (most certainly) the client was not properly educated in what to expect from a traditionally built table top with breadboard ends... 0:50 There is zero "problem" with air dried or even green lumber. This is, again, about skill sets and knowledge base in the craft of traditional working and joinery systems to use...and where. I mean that statement as a pure observation of fact and not a critical statement (in general) of the work presented in this video, which is good and well within the parameters of "modern wood machinists" that know little to nothing of actual traditional woodworking or the modalties in means application to be successful with it. Most DIYers and those that only learned woodworking by reading and following others that learned the same way simple do not know how to "read wood" or the many different traditional ways it can be successfully used dry or green...even for furniture... 2:50 You most certainly will have the same issues, often worse, with kiln dried wood. Wood is either going to contract (green wood) or massively expand (cooked wood) when it is used in application that employ traditional joinery. Too many today treat wood like plastics and or plastizied wood products like plywood or partial board...The later are industrial products and not natural ones... If you, or any reader of this, ever has questions (???) please feel free to reach out. The craft of "woodworking" in the historical sense has built most of what we have in wood architecture and artifact even to this day and most of that was built with "green wood" by the modern standard and understanding which is completely opposite of what you are stating in this video. There are even some wonderful books on the subject to get yourself going and more knowledgeable on the subject if a traditional apprenticeship or mentorship is not possible...

[@svonnestickley6311]

Do you heat up your wood to get the internal temperature hot enough to kill bugs? I am wanting to get into making end tables, night stands. And other furniture... and I'm terrified that I'm going to buy lumber that had bugs in it. Also, I'm really worried about the wood expanding and contracting that it will warp or do something to the piece I make.

[@JayCWhiteCloud]

@@svonnestickley6311 The simple fact is, historically, most things made of wood in "day-to-day" use by the average person from most cultures were made from "green wood" by today's industrial standards (and knowledge) of woodworking. What is actually the issue is skill and knowledge within woodworking...not any silliness that the wood has to be "kiln dried" to kill bugs or other nonsense... Are there items that need "dryer wood" than others? Yes, items like fine furniture in some styles or window frames, for example, need dryer wood and very selective species and grain patterns. I am currently finishing up windows for a restaurant pub project. The wood in these windows...WERE NOT... kiln-dried and are of a rather low-grade Yellow Pine, but because the project is supposed to simulate an 1840 Carriage Barn the client selected knotty yellow pine salvaged from a 150-year-old warehouse. This wood, when new, was used in the building while it was still green and thus dried in place, so it is air-dried and has worked just fine for building these window frames... Warping can be an issue with anything made from wood...DRY OR GREEN...!!!...such as end tables, nightstands, and related items. This is all about learning to work wood properly be it green or otherwise...not whether it can be done or not...I recommend finding someone who can mentor you in the process and/or reading good books on the subject like: "Make a Chair from a Tree An Introduction to Working Green Wood" by J. Alexander or "Joiner's Work" by Peter Follansbee... Feel free to ask more question if you have them...

[@wandameadows5736]

If you not making mistakes you're not learning.

[@BradyHommel]

Ain't that the truth!

[@jacobsimpson347]

Happened because you didn't let the wood dry to indoor humidity levels. Kiln dried will warp if you use it outside like wet wood inside.

[@squaaam2263]

does this mean for outdoor applications, air dried is the superior option? and the inverse? (kiln dried for inside is best option)

[@jacobsimpson347]

@@squaaam2263 not superior. But moisture level will be where it needs to be to avoid warping and cracking. Nothing wrong with kiln dried set outdoors to acclimate. Check out thermally modified wood

[@vharboe]

@@squaaam2263keyword here is acclimatizing. The wood needs to be at or near the moisture content it will have in the target environment, regardless of the starting point. Outside it will generally be between 12 and 19% moisture content, inside 7-9%. In very dry or wet climate areas, the numbers will be different of course.

[@squaaam2263]

@@vharboe Yeah, i know this a year later & feel dumb for even asking cause i wrote a paper on hydroscopic regain since then… but thank you so much for being polite with your answer! lot of people don’t know the difference between a question & a insult these days

[@vharboe]

@@squaaam2263 No stupid questions, only stupid answers. :) At some point, the wheel had to be invented. No point in blaming the guy for not having thought about it sooner! :) The same thing goes for knowledge. Even though the question was answered for the most part, I thought it would be a good idea to leave a bit more information on the subject. Because geeking out over it is fun! :) And someone might just need that info at some point.

[@David-fv7zg]

5:00 I have to disagree. Air dried lumber in not appropriate for any climate controlled room in a house, no matter what room it is in.

[@gwstubbs7046]

Too bad this happened.

[@BradyHommel]

You live and you learn.

[@pamtnman1515]

No. You misunderstand the nature of barn wood, which is subjected to wild extremes. All air dried lumber that has set long enough is stable. Kiln dried wood will eventually re-absorb ambient water. Barn wood needs to be left in the room in which it will be used for several months, and then it will be acclimated. To THAT room. Any room near a fire source is going to be drier than more distant rooms, and subject any wood to forces not found elsewhere. Don't make this issue worse than it is.

[@jacobsimpson347]

And throw that moisture meter out. Get one that has probes. No reason to know the moisture level of the outside of the lumber

[@Swarm509]

Look up how the probe-less meters work, it penetrants roughly 3/4" into the wood with the detection field it uses and doesn't just detect the surface moisture.

[@victormcox]

Better be careful brother, you said your customer was basically a kiln dry for the first table! They'll send you a bill for that!!😂

[@BradyHommel]

😂 haha you're so right.

[@ianmoone2359]

The problem with your table top is with you lack of understanding basically. Rule of thumb for air drying is “one inch of timber per year PLUS A YEAR. So 2 inch thick timber will require 3 years not two. Then there’s your lack of a moisture meter. Fair enough, like most other idiots I see on KZbin showing moisture meters and how to use them, you didn’t get a correct reading because you didn’t apply any of the species correction factors nor temperature correction factors. 🙄 The meters when they come out of the factory are graduated to read Douglas Fir. So for any other species you have to apply a “species correction factor” then a temperature correction factor to the obtained meter reading, to get an accurate moisture content reading. If you ran a timber seasoning kiln as I did for decades, your test piece towards the end of the 3 months drying cycle comes out hot (up to 50 degrees C (122f) so that’s why the temp correction factor needs to be applied. I did create a KZbin video on species correction factor. kzbin.info/www/bejne/eJykhpaJq7ehppYsi=rAfr6JQqxdi5-W9p Next theres the 3 different types of moisture contained within wood that needs to be removed. You have “free moisture” ( Sap) that runs up the tree from roots to crown for photosynthesis to occur. It runs freely between the cellulose wood cells. Then you have moisture trapped within the cellulose fibre cells, that’s called “intercellular moisture. Lastly you have “Intra-cellular moisture” & that’s trapped within the cellulose fibre cell walls itself. So the cellulose fibre cells are double walled - imagine two rubber balloons - one inflated within the other to leave a gap between the two balloons. That’s where the intracellular moisture resides. That double walled cellulose fibre cell has “pores” within it (called “lumens”, through which the intercellular moisture - the moisture inside the inner balloon has to diffuse out as a gas. If you draw the free moisture (sap) out too fast, you create a pressure differential between the inside of the cell and the gaps between the cell where the free moisture (sap) travels up the tree from roots to crown & that pressure differential has to try and draw the intercellular moisture within the cell - out through the lumens (pores) faster than it can diffuse as a gas and the cell walls collapse ( a condition called structural collapse in kiln dried timber) where the timber collapses well below its dawn dimension and goes all powdery and can’t be machined, sanded or polished - ie useless. This is why timber seasoning kilns are run on a drying schedule that takes time - for hardwoods up to 3 months. A lot quicker for softwoods because they have 2 grain directions , tangential & medullary rays, so are less susceptible to structural collapse from being seasoned too fast. The difference between hardwoods and softwoods isn’t the density of the timber. It’s actually how the tree reproduces. Hardwoods by flowers, nuts and seeds, softwoods by cones and spores. Balsa wood for eg is one of the least dense Timbers on the planet, it’s very soft, but because the tree reproduces by flowers nuts & seeds Balsa is a very soft hardwood. Then there’s the equilibrium moisture content, the moisture content at which the annual difference between summer and winter shrinkage and expansion is the lowest. Radial & tangential grain sawn lumber even once dried to its EMC (Equilibrium Moisture Content) shrinks almost nothing longitudinally usually less than 1% But radial & tangentially that same lumber can and will shrink up to as much as 6% on each board. This is x why breadboard end tables are just a dumb idea - design wise they will always do what yours has done. That’s not your fault if the customer asked for a breadboard end table design. Different if you decided to do that & they didn’t ask for it, then your liable to repair / replace it. It seems like maybe I need to create another video about timber technology to go with the correct use of moisture meters one I already created. The number of wood workers on KZbin who know nothing of timber technology astounds me. It’s become basically the blind leading the blind. For all the good that KZbin can do in teaching people things they never learned in school it can be just as bad at promulgating falsehoods as if they are facts. 🙄👎

[@andrewupson2987]

That "rule of thumb" is also pretty meaningless unless you're dealing with a dense hardwood like oak and you live wherever the "rule" originated, probably New England. And even then it's probably wrong. Douglas Fir where live, even if cut 4" thick, will air dry to 12% in about 3-4 months if milled at the start of summer. A common hardwood here, the red alder might only need a couple more months at that 4" thickness. Even our maples will be as dry as they'll ever get in 1-2 years depending on how well it's stacked, even at 4" thick. And if transported to someplace that gets legitimately hot, and is arid, those same woods will air dry much faster still. Would still be good to kiln it just to sterilize the wood though.

[@awoodmann1746]

Plywood is better!

[@J.Eddie.T]

You're blaming the wrong issue. You started with dry wood and built it after it rehydrated. Stop blaming the wood. Air dried lumber is just fine. Wood moves the same no matter how it's dried when compared at the same moisture content. And a kiln in your basement is not a great idea. Do it in a garage or sealed outside.

[@tomrodriguez9052]

If you are going to be serious about woodworking you need a climate controlled shop and store your wood in it, at least what you are using for your next few projects. I use almost exclusively air dried lumber, stored in my climate controlled shop, and never have issues with it. It's a myth that air dried wood is less stable and will never be as dry.

[@BradyHommel]

Good to know! Climate controlled shop is a must at my next place! Thanks

[@michaelgavin7621]

100 years of lessons lost.

[@thehoarsewhisperer1929]

I got to be honest 5% is low, even for kiln dried… they must have heated their house like the Sahara desert 😳

[@smellygoatacres]

Wow. Ever hear of EMC? Kiln dried is fast dried. Kiln dried will reabsorb moisture relative to it's surrounding humidity levels. Don't make excuses for poor craftsmanship.