# Wood expansion--why I doubt.



## FreeRangeWoodworker (Feb 22, 2017)

One of my favorite YouTube woodworkers made a comment in one of his great build videos that expansion is something to worry about with wood flooring, but not really with furniture. This certainly runs contrary to conventional wisdom, so it got my attention. I Googled examples of damage from wood expansion and the only images that came up were of wooden floors. There are endless articles and videos about how we have to account for expansion in tables and other projects that are much smaller than a floor, but I haven't seen any photos of such damage.

I'm not looking for explanations of why we have to account for expansion and contraction-I get the concept. I'm interested if anyone has pictures of your own work (not from the Internet) or even stories of your own experiences (without pictures) where you know the piece failed because of expansion and contraction and not some other factor.

Thanks!


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## RubberDuc (Dec 16, 2016)

As someone who has never fully understood expansion issues, I'm very interested to follow this thread.


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## Unknowncraftsman (Jun 23, 2013)

The best way to discover the power of wood is to do some experiments.
Try this one make a frame and panel out of solid wood.Make the corners of the panel real strong.Mortice and tenon or bridle joints. Fit the panel real tight with no room to expand.And glue it real good on all sides.
Wait and see what happens.

Aj


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## firefighterontheside (Apr 26, 2013)

Early on in my woodworking, I built a table where I did so many things wrong. I didn't use breadboard ends, but instead I mitered the corners. This table is pin oak that I had milled, but didn't allow to dry long enough. I did not have a moisture meter at the time either. Well, one night there was a Big Bang in the dining room. Several things fell off and got knocked over on the table. In one big movement the interior glueup of my table broke at a glue joint.


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## Snipes (Apr 3, 2012)

I think u should find a new favorite on that there youtube..


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## sawdustdad (Dec 23, 2015)

Museums and antique shops are littered with examples of failed joints and cracked panels due to cross grain construction methods. In the 18th and 19th centuries, homes did not dry out in the winter like they do now. So not as much care was taken to prevent shrinkage from causing damage.

Bring those pieces into the modern home and the joints open up and panels start to crack. I have an 1850 walnut chest of drawers that has sides made from single 20 inch wide boards. Both sides have cracks about 1/4 to 3/8 wide down the middle of the panel due to shrinkage. The drawer runners are nailed and glued, but have come loose in many places. The chest has moldings around the top and bottom that have prevented the panel from moving as a whole. I recently restored this chest, but there is nothing that could be done about the cracks in the side panels without rebuilding the chest from scratch. That particular chest is shown here.










Here is a modern example. this shaker walnut chest has a top surrounded by a molding. It's glued across the front but is mounted via a sliding dovetail on both sides and is glued only at the front. That is to allow the panel to expand and contract. During the winter, the 22 inch wide panel shrinks about 3/16 and the side moldings stick out at the back edge. This is how cross grain construction should be done to allow for wood movement. In the second front view, you can just make out the small molding protrusion at the back corners.


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## TungOil (Jan 16, 2017)

https://www.extension.purdue.edu/extmedia/fnr/fnr-163.pdf

Everything you ever wanted to know about wood expansion and contraction


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## WhoMe (Jul 9, 2009)

I agree, you need to find new favorite. We made some laminate tops for some ship stands. These were 8/4 thick and about 1"+ wide. The tables are roughly 20" - 22" wide so there are about 20 strips glued up. This wood had been in the shop for a long time and was well seasoned. We did bread board style ends but just butted the pieces up to the end. We glued and screwed the center and screwed the ends of the bread board with elongated holes for movement. The tables have polyurethane on all surfaces and the they still shrunk almost 1/8" per side over time. Almost 3/16 - 1/4" total.
If these would have been a fully glued and screwed end caps, im sure we would have joint failures on all the tables. 
Wood movement needs to be taken into account when designing furniture.


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## wormil (Nov 19, 2011)

I've built a number of tables, the only one to ever have a problem was the first one which was finished on the top side only. Years later it was placed near a floor register, the bottom dried out, shrank, and cupped badly snapping the wood buttons. I was able to fix that table but other tables I've built that were finished top and bottom equally have been in that same spot and none cupped.

My FIL built a solid wood post and panel headboard but glued the panel, within months it tore itself apart. I tried not to tell him but he asked where it went. He gave up woodworking after that.

A lot of YouTube woodworkers are beginners and you shouldn't depend on them for advice. There are many known experienced woodworkers that have written books or articles from whom you can learn properly. The Tage Frid book trilogy is a college course in woodworking.


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## Tabletop (May 9, 2016)

One of my first builds, over 20 years ago, was a 6/4 red oak table top attached to a metal frame. Lumber came straight from local saw mill and he had told me to let air dry for at least 1 year, (what did he know lol.). I got anxious, in other words tired of my wife nagging me about it and built it after about 3 months drying. A beautiful top with 3 coats of poly, top and bottom. After a few months noticed a hazy finish, first sign wood was not dry, but still looked pretty good. Everything was fine for about a year and then we noticed one side was no longer attached to the frame. I had secured top to the metal frame with screws about every 16" in all directions. If I recall correctly almost 1/3 of them had snapped and top was now cupped. Just one af many examples of me learning the hard way. Lol!


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## Tony_S (Dec 16, 2009)

> https://www.extension.purdue.edu/extmedia/fnr/fnr-163.pdf
> 
> Everything you ever wanted to know about wood expansion and contraction
> 
> - TungOil


This is a very well written, easy to understand paper. Aspiring wood geeks, and veterans as well should have it bookmarked.
It starts with an emphasis on equilibrium moisture content and it's relation to region, and climate changes throughout the different regions(the most important factor).
It gives the reader a good understanding of the hows and why's of design failure, and how to avoid it. Read it, understand it, and accept it.
Too many people here, and in the rest of the nether's of the internet, make broad sweeping declarations, some veterans included, that are nothing more than complete horse ********************.
What works(or what you can get away with) in one climate/region, may suffer anything from partial, to absolute failure in another.
Wood breaths and moves…period. To what degree depends on a variety of factors, including climate, stability of relative/ambient humidity, kiln dried vs. air dried lumber, type of wood, cut of wood, finishing techniques, etc.
I live in a ********************ty climate for solid hardwood construction….I've seen it, and I live it everyday.


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## EricTwice (Dec 9, 2016)

Look up where he lives.

I grew up in the western deserts. The humidity is usually less than 5% and wood movement is no issue.

However, I have lived in Florida which has a very high humidity and wood movement is a very real problem. I now live in the mountains of Virginia which is somewhere in between the two.

Western Colorado expansion gap for 18 inch panel is 1/16. (You also find that hide glue is a bad choice here. It will dry out and crumble to powder from lack of humidity)
Florida the same panel would get 1/4 inch gap and that may not be enough if the wood is very dry when it is built. I have seen many explode from a panel that expanded too much.
Virginia 1/8 is generally enough, but I would allow 3/16 just because.

Woodworkers have traditions for a reason. If they say you have to allow for the wood to expand and contract and someone tells you otherwise, ignore it and keep with tradition just to be safe.


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## rwe2156 (May 7, 2014)

Sawdust is 100% correct. It is true lots of antique furniture was built with little to no regard to movement because the environment in the shop was the same as a house. We can't get away with that anymore.

I recently completed a double dresser. There was one particular drawer that drove me nuts trying to tune it. It was almost there but I decided to let it go.

Well, after only 3 weeks inside the house, guess what, that drawer is sliding like silk!

And, this, even tho I built the piece in a climate controlled shop - in winter - ah, but in FL .


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## shipwright (Sep 27, 2010)

> This is a very well written, easy to understand paper. Aspiring wood geeks, and veterans as well should have it bookmarked.
> It starts with an emphasis on equilibrium moisture content and it s relation to region, and climate changes throughout the different regions(the most important factor).
> It gives the reader a good understanding of the hows and why s of design failure, and how to avoid it. Read it, understand it, and accept it.
> Too many people here, and in the rest of the nether s of the internet, make broad sweeping declarations, some veterans included, that are nothing more than complete horse ********************.
> ...


Hey Tony, I just love the delicate, diplomatic way you write your posts!
.... and it helps that you are always right…


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## Manitario (Jul 4, 2010)

Wood expansion is real and a problem for woodworkers. I've had two panels on frame and panel doors for cabinets crack because I didn't leave enough room for expansion. Average humidity where I live ranges from 30% in the winter to 70-80% in the summer.


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## jimintx (Jan 23, 2014)

> I agree, you need to find new favorite. ...
> 
> - WhoMe


Who is the woodworker that is mentioned in the opening post here? 
Thanks


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## JayT (May 6, 2012)

Several years ago I ordered some really nice looking vanities for a couple of the hardware stores I buy for. Unfortunately, the vendor spec'd glued-in solid wood recessed panels on the sides-about 14in wide and 2ft tall. I didn't find that out until the first winter and every single vanity had splits and cracks up to 1/4in wide from the wood drying and shrinking. We requested, and got, a refund from the vendor and I got to spend quite a bit of time trying to explain to them why using plywood would have been a better choice.

As for that favorite YouTube woodworker, I agree with the others-find a new favorite. Admire their designs if you want, but if they are making a blanket statement about not needing to take wood movement into account for furniture, I wouldn't be taking any joinery or other construction technique advice from them.


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## fivecodys (Dec 2, 2013)

This is not really a furniture example, but I made a zero clearance insert for my table saw like I have seen so many folks do on YouTube. I was so proud of how tight it fit in its opening. My shop, like many of you, shares the garage with the wife's car. I went out to use the saw and the zero clearance plate had expanded and really wedged itself in the saw. I ruined it trying to get it out.

Yes wood expansion really happens.


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## 280305 (Sep 28, 2008)

Wood Expansion is a hoax perpetuated by the Chinese government so that they can undermine the US fine furniture business!

OK, maybe not.

Have a look at Steve Latta's article Learn from Antiques: Avoid construction mishaps by looking at mistakes from the past in FWW #255. I am pretty sure that Steve is not an operative of the Chinese government, although how can we really be sure? I am involved in our town's historical society. We have some antique furniture in the museum that shows exactly what Steve writes about.

I had an interesting experience that I posted here:
http://lumberjocks.com/topics/59086


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## Ted78 (Dec 3, 2012)

I agree the issue is overhyped. Not that wood doesn't expand and contract, but it is usually a visual problem rather than a structural one, ie gaps appear where you would rather have a nice smooth surface. Frame and panel doors that get painted so as to 'glue' the panel to the frame always crack. Look at the doors is just about ANY house built prior to 1920 or so. The panels really will buckle it you don't leave enough space for them to expand as well, a much bigger problem than just a crack. The thinner and wider and the more 'finished' a piece needs to look the bigger the issue. So floors, large table tops that need to look pretty, panels of frame and panel construction.

Barn doors, big pine tool or sea chests, are large and flat but crack or two or being a bit out of square is not big deal on these more utilitarian things.


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## jerryminer (Jun 15, 2014)

> .... I haven t seen any photos of such damage…..
> - FreeRangeWoodworker


This is not my project, but came from another Lumberjock. Ignore wood movement at your own risk.


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## pottz (Sep 15, 2015)

i made a end table out of solid ipe years back in the winter time,after being in the warm house a few months a 1/4 gap opened up,luckily i was able to hide it with inlay work.im curious as to what woodworker made that statement myself,if your willing to rat him out.


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## Tony_S (Dec 16, 2009)

> Hey Tony, I just love the delicate, diplomatic way you write your posts!
> .... and it helps that you are always right…
> - shipwright


Hmmmm….
Paul….I have 2 ex-wives, 3 kids, my Mom, and about a half dozen guys in the shop you need to speak to! lol!


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## FreeRangeWoodworker (Feb 22, 2017)

You guys totally rock. One reason I love woodworkers is that you are so willing to share your knowledge and experiences.

I re-watched the video of the YouTube woodworker, and I picked up on a couple of things. One-he said use dry wood (12% or less), and two-he said that he is only speaking for the geographic area in which he lives, where the humidity is fairly stable. And I noticed that everything he makes stays in his area, so it's not like he makes stuff in Nevada and ships it to Florida.


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## FreeRangeWoodworker (Feb 22, 2017)

Esp, thanks for all the photos.


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## FreeRangeWoodworker (Feb 22, 2017)

And, by the way, you guys rock.


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## AZWoody (Jan 18, 2015)

> You guys totally rock. One reason I love woodworkers is that you are so willing to share your knowledge and experiences.
> 
> I re-watched the video of the YouTube woodworker, and I picked up on a couple of things. One-he said use dry wood (12% or less), and two-he said that he is only speaking for the geographic area in which he lives, where the humidity is fairly stable. And I noticed that everything he makes stays in his area, so it s not like he makes stuff in Nevada and ships it to Florida.
> 
> - FreeRangeWoodworker


I live in the desert in Arizona and still I get movement. It can be a very dry average humidity but there are huge swings throughout the year. Monsoon season brings in high humidity along with high heat and that causes havoc in my shop. Usually up to 3-4 days after a rain I avoid doing any work in the shop because even my "stable" wood will have movement.

Even then, it does not take a large change in humidity to make wood open a joint enough to make it unsightly. 
Also, I would not consider wood that is 12% moisture, dry. especially in the desert. In the average dry season, that wood will drop easily 4% to 8% and it can be pretty quick.

Now, I'm not an expert and I don't weigh the wood or do anything scientific. I have watched it happen in the shop and I have weather stations around my farm and I check the weather daily because I have to schedule based on weather so I keep track of that constantly. Then I compare it periodically with what's going on with the wood in my storage shed and what I have drying from the sawmill.


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## 000 (Dec 9, 2015)

If I were to move out east, I would completely have to be retrained.. 
Feel kind of spoiled here out west, you can get away with quit a bit.


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## TheFridge (May 1, 2014)

I watch my 20" benchtop expand to about 1/4"-3/8" more than my vise chop during the year. Then notice the width is same as the length later on.

Back in the day they would drill holes in rock. Hammer wood in there and pour water in it to break the rock. Or something very similar to.


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## lumbering_on (Jan 21, 2017)

> You guys totally rock. One reason I love woodworkers is that you are so willing to share your knowledge and experiences.
> 
> I re-watched the video of the YouTube woodworker, and I picked up on a couple of things. One-he said use dry wood (12% or less), and two-he said that he is only speaking for the geographic area in which he lives, where the humidity is fairly stable. And I noticed that everything he makes stays in his area, so it s not like he makes stuff in Nevada and ships it to Florida.
> 
> - FreeRangeWoodworker


I know the video you are talking about and he lives in Victoria, BC. I used to live in the same region, and the temperature rarely goes below 0C/32F and doesn't climb much above 28C/82F. It's also right on the Pacific ocean so the humidity doesn't change much. I now live in Ottawa, ON, and the humidity here ranges from bone dry in the winter (RH < 20) to 100% in the summer. He'd have a lot of unhappy customers if he did the same thing here.

Although I generally like his videos, in this one he generalizes too much, and is passing on flawed information.


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## ArtMann (Mar 1, 2016)

The reason you don't see too many examples of failed projects due to wood expansion/contraction is that pros and experienced amateurs already know how to deal with the problem and people who make such mistakes are not all that excited about publishing them for all the world to see.


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## SignWave (Feb 2, 2010)

I made a box out of some old and very dry cedar. I thought it was small enough (about 12" x 12" x 4")that I could just glue the top/bottom/sides and that movement would be minimal. The bottom piece ended up splitting due to shrinkage.

Some people like to buck tradition, particularly widely repeated "common knowledge". I have no problem with that, but reality is what it is. If you're curious, do your own experiment. You'll learn something from it, almost certainly more than watching any video.


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## bondogaposis (Dec 18, 2011)

I have seen several dining room tables that split due to lack of allowance for wood movement. Unfortunately I don't have any pictures. You can see it in junk and antique stores where dresser tops split or tables, etc. You can't count on furniture not getting moved around the country, nobody can predict the future and know with certainty where we might be living in the future. After you pass on all bets are off on where your stuff might end up. I like to think that the furniture I build will out last me by a long ways, no matter where it is.


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## Gilley23 (May 9, 2017)

Ok so someone please post a link to the video in discussion so that we can all learn a little more about the topic.


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## AlaskaGuy (Jan 29, 2012)

Wood is hygroscopic just like a sponge. Put in the water and it will swell up. Put it in the oven and watch it shrinks. If a piece of wood has reached its' EMC and the relative humidity goes up wood will suck up moisture out of the air and expand. If the relative humidity drops below the woods EMC it will give off moisture and shrink.

You can find chart that will tell you what the EMC of you wood should be at a given temperature and relative humility level.

Like this,
https://www.finewoodworking.com/FWNPDFfree/equilibrium-moisture-content-chart.pdf

***Equilibrium Moisture Content (EMC)


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## lumbering_on (Jan 21, 2017)

> Ok so someone please post a link to the video in discussion so that we can all learn a little more about the topic.
> 
> - Gilley23


Unless I'm way off base, this would be the video.


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## wormil (Nov 19, 2011)

The comments are hilarious.


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## JAAune (Jan 22, 2012)

I've seen damage caused by expansion/contraction when doing furniture restorations. Inevitably, some well-meaning person tries to repair failed joinery by screwing a solid wood desk top into the apron around the perimeter. The result was a top that had multiple splits running down the grain.


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## oldnovice (Mar 7, 2009)

When I was in junior high drafting class, a few years ago, we all had to buy our own portable drafting boards per the requirements set by the instructor.

Each drafting board had vertical wooden edge's (for the T square) on either side of a field of several horizontal joined boards (I would post a picture but I went to Jr high so long ago that the only pictures were carved on cave walls).

These T square edges normally went completely from the top of the drafting board to the bottom which was the way they looked when it was purchased.

Coming back to shool after a weekend many of the students were surprised that these vertical edges did not reach the entire height of the board as the school was not temperature/humidity regulated over the weekend. During the week the T square edges "grew" back to normal size.

That was my first exposure to wood shrinkage and I have not forgotten!


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## Harryn (Apr 25, 2011)

I have just finished rebuilding and restoring a 100 year old blacksmithing bellows. It was made with 9" wide pine boards edge glued. Over the years these joints opened up as much as 3/16"due to expansion and contraction. 
Obviously It would not pump air with these leaks. All the glue had turned to powder. It probably was hide glue.


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## edapp (Jun 27, 2014)

I thought that was just a natural progression into woodworking as a hobby. As someone who started with a simple Anna White plan and pocket hole jig, several of my first projects suffered damage from wood expansion/contraction. Without proper instruction/formal learning, I learned as I went which means many of my first tables do not look or function in a way that they were originally intended. Anyone who says wood doesn't expand/contract hasn't done much fine work with wood.


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## TheFridge (May 1, 2014)

That's the problem with the Ana White stuff. Apparently not enough pics of failure have been sent to her to convince her that it's a problem.


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## AlaskaGuy (Jan 29, 2012)

> That s the problem with the Ana White stuff. Apparently not enough pics of failure have been sent to her to convince her that it s a problem.
> 
> - TheFridge


I have often wondered how her farm table hold up over time. I'm sure they don't in many many cases if not all over time.

This video should be titled " how not to do it". She says she builds her table base stronger the the table top and that take care of warping (no comment about wood movement). Bread board ends are glued and screwed. How this woman says in business I don't know. She must be laughing all the way to the bank.


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## lumbering_on (Jan 21, 2017)

> That s the problem with the Ana White stuff. Apparently not enough pics of failure have been sent to her to convince her that it s a problem.
> 
> - TheFridge
> 
> ...


I'm not an expert by any standard, but I've built a few table tops, and that is the first time I've ever seen someone use pocket screws. It's also the first time I've seen it done without laminating the boards. Seems like a rather slapdash way to do it.


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## oldnovice (Mar 7, 2009)

The first comment on this video should be *HOW NOT TO BUILD* a table.
Perhps she only expects them to last a few weeks!


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## EricTwice (Dec 9, 2016)

I live in Virginia, but I have worked in both Florida and western Colorado

I have seen some pretty crazy stuff when it comes to wood movement. 
If you are building a raised panel door; Florida 3/16 each side (3/8 total maybe more), Western Colo. 1/16 total, Virginia 3/16 is generally enough. (depending on wood species)
I have seen doors explode and tabletops split in half, and a lot of other things that I don't have time to write about.

Anyone who says wood movement is not an issue should be politely ignored.


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## ArtMann (Mar 1, 2016)

My opinion is that anyone who says wood movement is not an issue on these forums should be loudly contradicted. There are too many beginners who could make some very bad design decisions based on such a falsehood. I think accuracy trumps politeness in this particular case.

One example I will offer was made by a very skilled guy I know who built a beautiful chess board out of solid walnut and maple blocks. He built an elaborate surface and frame around the board and it finished up nicely. Over a few months, the blocks expanded and forced open the joints at the corners of the frame. He is no longer proud of his accomplishment. This outcome was entirely predictable and could easily have been prevented.

On the other hand, I have seen comments that I would only describe as hysterical having to do with how much wood will expand and contract due to humidity changes. Unlike what the the dummy in the video link above said, this wood property is highly predictable. Expansion and contraction of various wood species over humidity changes have been measured and documented and are there for anyone to use. There are even web pages that will calculate the changes based on species, grain orientation and humidity changes. All you have to do is ask yourself what will happen to your project if that kind of change happened. In lots of cases, the answer is absolutely nothing. In several other applications, expansion and contraction can be compensated for by the use of fasteners rather than glue. Without even slotting, screws will have some ability to move with dimensional changes and compensate for expansion and contraction. In other cases, you have to take extreme measures to avoid self destruction.


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