Furniture Building For Beginners - How to Deal with Wood Movement

[@tfields6364]

This is the best explanation of wood movement I''ve seen. I knew enough to be afraid of it - and avoided using solid wood in drawer bottoms because I wasn't clear on the mechanics. Seeing multiple pieces of furniture explained all at once helped bring it all together. Thank you!

[@lacarpenter31]

Rob Cosman's instruction: when perfection is the only acceptable standard. Thanks for sharing your knowledge.

[@Mom2MrBabyHaikin]

I just found this channel. He explains so reachable for beginners like me & I'm realizing how hard it would be to make my son his captains book head board storage bed. WoW! Still, so interesting!

[@matthewbrady5214]

There are so many videos about tools, but this is the best video I have seen on construction

[@AntonRiddell1810]

For someone of limited knowledge of the behaviour of wood, this is a superb video Rob. I’ve learnt so much in that 20+ mins. Thanks. Appreciate the great advice you give.

[@RobCosmanWoodworking]

Thanks for watching and commenting

[@shemoe99]

10 children!!! God has blessed you my friend. So happy to hear that pice of info during your educational video.

[@rsrrhino]

I've been watching your videos for a long while. I always enjoy them and get something from them. This might be the most informative video you've made. I don't think anyone has done a more comprehensive lessen, on KZbin, about wood movement. Thank you.

[@hunterp5495]

Thank you. This is extremely informative. You explained everything really well. What a great teacher.

[@tzavitz]

Terrific! That’s the best explanation I’ve heard about this! Easy to understand and the simple techniques are great for a beginner.

[@RobCosmanWoodworking]

Thats what we were shooting for

[@fredzaspel7350]

Very, very helpful video. Thank you much.

[@thewoodlesworkshop.157]

Dear Rob. Once again I want to thank you for sharing your invaluable experience in carpentry. I watch all your videos with pleasure and attention, and I constantly discover a lot of interesting and useful things ... Take care of yourself there. :)

[@RobCosmanWoodworking]

Wow, thanks

[@mikedecker2917]

I really enjoy and appreciate the teaching style and high quality content this team produces. I look forward to Robs teachings on a daily basis and have immersed myself into his KZbin classroom. I can’t wait to get my Cosman dovetail and fret saws. If his tools are as good as the educational content in these videos, my personal joy and skills will grow exponentially. Finally, anyone that supports our veterans the way he does earns my full support and respect. Thank you Rob and crew.

[@RobCosmanWoodworking]

It’s both our honor and privilege to help these folks, the least we can do!

[@Franco.Ar.]

Great video I have been looking at this issue a lot lately... I have worked a lot with engineered materials, and the design challenges for solid wood are just so fun to work with.

[@RobCosmanWoodworking]

Thanks for sharing!

[@christunks7512]

Brilliant video. Thank you!

[@vincentfaure4472]

Clear information and beautiful examples to illustrate the point. Thank you very much for sharing.

[@RobCosmanWoodworking]

Thank you for watching and commenting

[@MrKaremoller]

Great explanation and good solutions :)

[@redrockcrf4663]

Rob - at about 5:15 you're going over dimensions and explaing about the top's instability vs the length of the side supports not moving. Can you PLEASE explain why the width of the side supports being captive to the legs isn't also a problem, as they get wider and narrower. This pieces look wider than the box top shown at the beginning of the video, so we should expect expansion and contraction of them also - no??

[@davidkoba]

Everytime you walk past your work table I can't help but admire that bird's eye maple....

[@RobCosmanWoodworking]

Thank you, I love birdseye

[@passg1920]

Magnificent presentation Mr. Cosman. You are a true master and educator. Thanks for sharing so much knowledge.

[@RobCosmanWoodworking]

You are very welcome

[@SamuelCersosimo]

What a lesson! Thanks!!

[@frankcornfield5915]

Thanks for this great video with examples of the different situations and how to deal with them.

[@AdamKirbyMusic]

I was literally just looking up videos on this problem today. Thanks for this!

[@RobCosmanWoodworking]

I sensed that so we made this one for you

[@Jethrot1982]

Same! how weird!

[@roryconiglione9486]

The dowels to table top is brilliant

[@RobCosmanWoodworking]

Thank you, I liked the idea

[@mohameddocrat4393]

Very well presented and explained. Thanks

[@RobCosmanWoodworking]

Glad it was helpful!

[@milesjay2330]

Thank you so much for this insight. These are such creative solutions... much appreciated!

[@TeamProsperity]

Great way to secure drawer bottoms, i love that method. I’ll use that method from now on. Great video Rob

[@RobCosmanWoodworking]

Glad you found it useful

[@animalivaganti360]

Another exhaustive lesson. Thanks so much Rob.

[@RobCosmanWoodworking]

thanks for watching

[@J.A.Smith2397]

Very comprehensive,as the norm, which is tough for this subject

[@RobCosmanWoodworking]

Thanks for watching and commenting

[@howardyounger5456]

great video. I learned the hard way. I built a dinning table out of oak. it was beautiful. but i had the grain running two different directions. that was 35 years ago it is still being used but has cracks. thank you for the great videos.

[@RobCosmanWoodworking]

Its happend to all of us

[@ricardomagnificent]

Great video. A warehouse of information.

[@RandomDoive]

Thanks Rob,really appreciated.

[@glockgrouptherapy]

Here's another question for you Rob: Im looking at building a No. 962 Server by Gustav Stickley. The lower shelf is through mortise and tenon along the bottom rail. The plan shows the tenon 1in shorter than the shelf overall width. How is lower shelf's expansion controlled to avoid blowing up the rails?

[@mypony891]

Thank you!

[@chaddyaniwcellist]

Very helpful, thanks very much Rob.

[@RobCosmanWoodworking]

glad you thought so

[@tedandersson8473]

Really great with all these examples in the same video. 👍. I will keep it for reference when needed.

[@RobCosmanWoodworking]

Glad it was helpful!

[@b.eophanrobson2222]

Possiblity your best video so far

[@RobCosmanWoodworking]

Wow thanks. What should we do next?

[@DesignEcologies]

Thank you

[@larrybarnes1305]

Great video, very informative.

[@RobCosmanWoodworking]

Glad you enjoyed it!

[@thefalcon666]

I've been curious about this for awhile now - great video, thanks Rob!

[@RobCosmanWoodworking]

you bet

[@TheTranq]

Good discussion Rob. Can’t wait for it to warm back up so I can get back in the shop

[@RobCosmanWoodworking]

You need to buy a heater!!!!!!

[@TheTranq]

@@RobCosmanWoodworking I know! Right now our garage isn’t insulated, but hopefully by the next year or two I’ll have my own space. Keep up the great content, so much to learn in all your videos!

[@waionpaingsoe4231]

Thanks

[@mattg6262]

Rob could you do a video about end caps on a work bench that account for movement?

[@RobCosmanWoodworking]

Its just a big breadboard.

[@iskato914six]

thanks Rob! I learned a lot :)

[@RobCosmanWoodworking]

thanks for watching

[@jackhadfield3943]

Rob saves the day agin!

[@RobCosmanWoodworking]

I did?

[@toddtremeer7057]

I've learned so much about woodworking on your channel. Thanks for sharing your expertise. What are your thoughts on wood movement on mitre & splined corners on picture frames etc? I'm wondering if this diagonal cut across the wood grain poses a problem with wood movement.

[@matthewitt2276]

Thanks Rob! Great video!

[@RobCosmanWoodworking]

Thnaks for watching

[@tadbarber2735]

Thank you so much

[@RobCosmanWoodworking]

You're most welcome

[@jwd888]

another information burst from a master of wood....youtube has some benifits afterall....

[@RobCosmanWoodworking]

Thanks for watching and commenting

[@jwd888]

..for someoe like me just starting a new venture I couldn't find the knowledge you have to learn from without the internet... its me that should be thanking YOU so i'll take this chance to do just that . Cheers for sharing your passion with the world...

[@thebutton7932]

inside an acoustic guitar is a small network of a variety of cross grain bracing, that holds the guitar together. some are glued at 90 degrees to the grain orientation of the guitar. . . But they DO have to be very careful about the humidity, when making the instrument, and all cross grain bracing is done at a specific humidity setting (low 40's? - Aust) that is considered a mid point in the timber's 'movement'. Usually all this is done in a de humidified room, or environment. In theory, that should allow for the amount of movement, EITHER WAY, that the timber may want to travel, during each year.

[@ChristopherPhillipsDev]

Hi Rob, great instructional video! How does thickness expansion come into play when you're building a bench top like your workbench in the video? The top is comprised of many pieces where the total width is number pieces multiplied by number of boards. I guess the height won't increase by too much because the board isn't very wide, but how does the compounded thicknesses factor in?

[@samz8023]

Love the details. Can the panel be glued to the rail in the middle only ?

[@RobCosmanWoodworking]

Yes. That way it is allowed to expand to the sides

[@BrantAerials]

Great tips. Thanks!

[@RobCosmanWoodworking]

You bet!

[@J.A.Smith2397]

A moving topic!

[@RobCosmanWoodworking]

Absolutely

[@jamessssssssssssssssssssssssss]

Excellent description and examples for the most part just got a few questions. Why doesn't the veneer on the box lid get split apart under its own force? If the MDF gets pulled with the veneer I would of thought that the border pieces of hard wood would restrict the MDFs movement. All of these examples are with thin wood so they have minimal movement across there thickness but how much movement can a piece of wood take before the pressure on well fitted joints or seems starts to become an issue?

[@jamartin1]

Thank you!!💜

[@RobCosmanWoodworking]

You are so welcome

[@PRRGG1]

I really enjoyed this video. I built a hall table and did ok. I knew NOT to glue or screw the top, It floats on clips at the stable ends. This got me to thinking about glues and is their a glue that allows for some movement but keeps parts secure?

[@RobCosmanWoodworking]

No, There is no glue that allows for movement

[@robertbamford8266]

A lot to consider. A question: on a panel door, what keeps the cross grain joints on the frame from separating? Are the rails just partially glued so the movement is all directed to the inside?

[@RobCosmanWoodworking]

No. The rails expand but since they are m&T / glued to the stiles all movement pushes to the outside, away from the joint

[@adrianb71]

Hi Rob. Thanks for this video. I am learning a lot from the excellent content on your channel. A question: I recently saw a tabletop made out of multi-species laminated strips, with a breadboard style border on all FOUR sides. This border was like a mitred picture frame that was glued to the tabletop all around. It looked really nice. But now that i've seen your wood movement videos, it seems like a bad idea! Is there a way to make this construction work? Thanks.

[@tylersmith8045]

Hi Rob- im a newer woodworker and building a bunk bed out of African Mahogany. Great video but i have a situation i cant figure out with expansion and contraction. Posts on my bunk bed are 1.5 inches thick and 6 inches wide and i want to attach planks of similar dimensions perpendicular to the posts- face grain against face grain to serve as the ladder rungs/cross supports. So both pieces of wood (placed perpendicular to each other, face grain against face grain) will experience contraction and expansion. I can use the screw/groove method to account for movement and minimize stress on the weight bearing posts but that wont allow for expansions/contraction of the cross beams. Any ideas?

[@sueb4154]

Hi Rob, may I ask you a question? Do laminated tabletops experience as much wood movement as large single pieces do? Should a tabletop of many glued up boards be secured in the middle with elongated expansion holes toward the outside of the top? Is this making any sense to you? I guess that wasn't really A question ... it was many. Thank you for all the crossgrain construction explanation. This is really an important topic, especially in tropical climates, if you want to be able to open and close your drawers or doors!

[@RobCosmanWoodworking]

Yes a top made up of many laminated boards moves. The question is in what orientation did you lamininate all the wood? The wood will move in its width (another way of saying that is parallel to th egrowth rings) so you must pay attention to how you orient the wood when you glue it up. You want everything moving in the same direction or you have created a cross grain situation

[@chrisrandall3690]

I noticed that the white pine table top you worked with had 2” band around it with mitered joints. What keeps the joints from separating when the width of the top increases?

[@RobCosmanWoodworking]

Thats not a band! Its a 1” solid piece of wood that I planned a big bevel edge on the bottom

[@aleksiharju1407]

What about if the drawer sides are made from quartersawn lumber and growth rings would be parallel to the carcass sides, that way you could make the drawer a little tigher top to bottom and take into account movement only in width, which would be miniscule?

[@RobCosmanWoodworking]

Then the fit side toside would change and the drawer would stillget stuck. Quaretr sawn doesnt mean it wont move, it just moves uniformly

[@kerrystimpson5111]

Thank you for such a great explanation and guide, working with solid wood. You always give me great information. I assume you are a BYU Grad. Go Cougars (i graduated "many" years ago). Thank you for sharing your expertise.

[@RobCosmanWoodworking]

Me too....whos the oldest?

[@kerrystimpson5111]

I am the oldest. I graduated in 1974. Just turned 70 this week

[@MohammedNatheer]

Tha was just on time for me thanks alot, I am confused a bit about the first example (the table) what about the frame of it, I noticed it is quite wide doesn't need a space for movement?

[@Jethrot1982]

The frame only uses wood with the grain running lengthways so the only movement will be that the frame becomes thicker and deeper. It's length should remain unchanged. Hope that helps

[@MohammedNatheer]

@@Jethrot1982 thanks alot, since it gets deeper and thicker the joint between the frame and the legs has to have some space for movement?

[@Jethrot1982]

@@MohammedNatheer I'm really not a knowledgeable woodworker so hopefully somebody else may answer. I think that given the narrow nature of the frame it would have little impact and as the majority of the material from the frame will be mortice and tennoned into the joint preventing it from spreading too much. As I say though, I really don't know much myself!

[@MohammedNatheer]

@@Jethrot1982 I thought the same, thanks again for your help 😊

[@RobCosmanWoodworking]

The answer is.....The grain in the aprons is oriented parallel to the floor, therefore all movement if up and down (in the woods width) and a little in thickness. The tenons have the same effect as afixing the board in the middle so all movement goes out the top and bottom the middle is fixed.

[@Jethrot1982]

Well this is weird. I'm looking to make a chess board and all the videos I watch show trim being glued around all four sides which I thought would be problematic for the all reasons you mention. I look for a video on tips to solve this problem, and low and behold you have released the perfect video today! Thanks Rob.

[@RobCosmanWoodworking]

Well the question is do you have any cross grain construction. Typically chess boards have pieces oriented with the face grai showing and the endgrain on the sides. SO when you attached a boarder to it there is no issue since it doesnt move along the endgran. If you built the other way it wouldnt be a problem as everything would move in unison

[@Jethrot1982]

@@RobCosmanWoodworking Thanks very much for the reply Rob. I'm still a bit confused though. Sticking with a facegrain construction (not endgrain up), if all square are orientated with grain the same way then I can glue two mitred pieces of trim onto two edgegrain sides but the other two sides will be endgrain, no? So I would have to put a breadboard joint for the end-grain ends or make thin squares attached to a plywood base. I hope that makes sense!

[@clifforddavis722]

Appreciate the content. Haven't seen any explanation of wood movement as good as this one. I always hear reference to it but it's usually not clarified. Thanks.

[@RobCosmanWoodworking]

Thats what we try to do so you can take your woodworking to the next level

[@mayobushcraft]

Many years ago I started building a 6 foot round oak table the client called to ask if they could postpone the build for a few months as they were moving. We set the table aside when they called back we retrieved the table from the back to finish the build and you could see how the top went from round to an eclipse. It was about 6 foot in length and about 6 feet 2 inches in width. This was in Florida.

[@RobCosmanWoodworking]

Yup.....Wood moves......What did you do?

[@mayobushcraft]

@@RobCosmanWoodworking Called the customer explained what happened. Told them we would reduce the ellipse some to make it less noticeable and added longer brackets to allow the top to shrink when they had it in there home. Fortunately they were understanding.

[@wonderwilds]

so, is a tenon to small to have to worry about, like on the tables legs?

[@derekrobertson1548]

As always thank you for the information and the video, these are always very helpful, well presented and informative. I do have a question, I am thinking of updating my kitchen, new cabinets, drawers, door fronts and counter top. When it comes to the worktop I was thinking of making this from solid hardwood, lots of thin strips glued together. Where the 2 worktops meat to change direction (90 degree (L shape)) how would i account for seasonal movement in the wood to stop a gap appearing where they join. I know you can get metal strips to fill this space but personally I think they look cheap and nasty.

[@RobCosmanWoodworking]

Well what I would do is laminate so all the movement goes upand down. When you join the corner do a big miter ($5 degree joint) and it will be endgran to endgrain, which does not expamd

[@harrysuber753]

Building a table. The top is flatsawn ash 48" wide (1.25" thick). How much expansion do I need to allow for? The location is the eastern shore of Maryland where it can be quite humid in summer.

[@RobCosmanWoodworking]

Hi Harry, check out Bruce Hoadley's book, "Understanding Wood". He has charts for different species of wood and how much they will move in a typical home from summer to winter.

[@jon0807]

For the door frame, wouldn't the rails expand? How do you deal with that movement when attached to the stiles?

[@RobCosmanWoodworking]

Yes the rails expand. One side of therail is glued to the stile but the oppisit side of the rail is in the opwn, so all movement of the rail will go away from the glue joint. The rail is alos samll so while it does have movement, its not much

[@jon0807]

@@RobCosmanWoodworking OK got it! Thank you so much for all your videos, I really appreciate the indepth information you provide!

[@glockgrouptherapy]

How thick of a veneer could you go before expansion is a problem when laminating to the mdf?

[@RobCosmanWoodworking]

Wow, I have gone up to 3/16's and never had an issue. So I dont know at what point it starts becoming an issue. Good question

[@glockgrouptherapy]

@@RobCosmanWoodworkinghmm.. Sounds like theory to test hahha! Thanks for the reply!

[@DennisHaney]

MDF moves about 0.3% vs solid woods 1-3%. So if you want to keep your expansion to 1mm on a 250mm lid you would need to keep the veneer below 7.5mm (9/32") in each end. With 2mm allowed expansion you can use up to 35mm in the same lid. If you use extra moisture resistant MDF with 0.2% expansion you could use a bit more.

[@glockgrouptherapy]

@@DennisHaney great info thanks!

[@CafeenMan]

I've played with wood my entire life and it still amazes me how much it can move. I've got to tell you, Rob, that even though I've understood this concept for a long time and know it to be a real thing I still always have a defect thought in my brain that won't go away. And that thought is, "Well, it will expand and contact but it won't be a problem if I glue all this stuff together." And because I have that genius thought none of my stuff could possibly be affected by actual physics, right? OK, so even though I have that stupid thought I still never go through with it because I know if I do whatever it is I'm building will explode - probably sooner than later. That said, I'm a model-builder mostly so in that realm the effect is so small that it can be effectively ignored without issue.

[@RobCosmanWoodworking]

yes size does matter. when its tiny there is tiny (neglagable) movement

[@josiahutah3712]

Greetings from Sandy Utah! I didn’t know you lived here.

[@RobCosmanWoodworking]

1983-84 then back from 85-89. Provo, BYU 89 Go Cougars!

[@garyrobinson6175]

In the edits vid you said you were reading from notes. Where did these notes come from and can I get a copy?

[@RobCosmanWoodworking]

They were notes that we use in our classes that we put together.

[@IvanWizard-Karl]

why is there always 1 or 2 clowns who dislike a fantastic informative video like this. It boggles the mind. Thanks Rob, Great resource is this video!

[@RobCosmanWoodworking]

They are called “no lifers”, only attention they can muster is to do the logical opposite of everyone else in hopes someone will notice them. I throw them a bone every now and again.

[@IvanWizard-Karl]

@@RobCosmanWoodworking i'd be more likely to throw a bone AT them, Cheers from Ireland, love your content.

[@boatrat]

Not just a climate difference from the Utah Desert to the "Coast": Also don't move from the East Coast, to the West Coast, and expect things to be the same. Continuous reference here to "Dry Winters" and "Humid Summers". Coastal Washington State, is exactly the opposite! The only normally "dry" period we have here, is called "August" LOL.

[@RobCosmanWoodworking]

So right you are....

[@Dravde]

I need help! How would you allow for wood movement in a square (90x90 cm; American White Oak) tabletop thats made out of 4 trapezoids? That's a lot of wood with a lot of movement.

[@RobCosmanWoodworking]

I dont understand “ made out of 4 Trapizodes? Write me with pictures at the contact us link at Robcosman.com

[@Dravde]

@@RobCosmanWoodworking, will do. Thank You!

[@Dravde]

@@RobCosmanWoodworking I sent a mail to the [e-mail], since "Contact us" link doesn´t allow the transfer of pictures. Waiting for a reply via mail.

[@laurencegoedar462]

Expand, contract, expand, contract...Focus!...expand, contract, expand, contract...Always look wood.

[@RobCosmanWoodworking]

dont foregt about the expansion and contarction!!!!!

[@Brough_builds]

I've recently glued up an oak desk top and stupidly left it flat on my bench for a few days due to an injury couldn't get back in the shop and now the desk top has cupped. Can it be pulled back flat or is it a now no good?

[@RobCosmanWoodworking]

Depends on how you’re holding it to the base. You can’t just reverse the cupping, but you can use the base to hold it flat.

[@Brough_builds]

@@RobCosmanWoodworking I'm fitting it to box section steel frame

[@1deerndingo]

You have and continue to provide such excellent, broad and in-depth instruction. It would be good if all this great instruction could lead to a tangible recognition of how well a student can perform. I just wonder if there is a way that a grading system could be available for the viewers. IE. A simple dovetale pencil box , hand tool done, might be level one. The student would pay for the service of assessment towards the Purple Heart Foundation. Could assessment be done by chosen volunteers via emailed photos. Volunteers may even do the admin for the whole thing. The student gets sent an emailed A4 certificate that clearly states that it was an assessment of the information emailed by the student.

[@RobCosmanWoodworking]

Interesting idea. Let me think on it

[@JonFordWoodworks]

Thanks for sharing! I always thought it was the LSD making the wood move, not the wood itself - I joke of course!

[@RobCosmanWoodworking]

Well I guess that could make wood move too!!!!!

[@yoelai]

Is it still a problem if every piece of wood is finished with something like polyurethane? If so, how can moisture escape the poly?

[@rjamsbury1]

Yes, it's always still a problem. The finish only slows down the change in moisture content.

[@RobCosmanWoodworking]

Robert is correct. No standrad finish stops moisture from entering or leaving the wood, it just slows down the absorbtion rate

[@imwithstupid086]

Never would've guessed that you like MDF. I personally don't. We agree with our dislike of particle board, though.

[@RobCosmanWoodworking]

Check out the new-to- me water resistant MDF, game changer.

[@Kennebec_Craft]

I watch every video, Rob, and buy tools as able. But my three year old said to my wife today, “I don’t like Rob Cosman Welcome to my Shop. Do you like Rob Cosman Welcome to my Shop?” Haha!

[@RobCosmanWoodworking]

Obviously, she is a budding critic !!!!!!!

[@bruinflight]

"...and... good luck!" ^_^

[@thefleetfarmer1815]

The ancient Egyptians use to drive (dry) wood wedges under giant slabs of stone, then flooded the area so the wedges would absorb water and they would expand and break loose the slab...🤯...look it up

[@RobCosmanWoodworking]

Thats because they couldn't freeze the water to crak the stone. That how it was done in the colder climates. Good trivia. Keep them coming.

[@sameulallard9289]

10 children holy cow.

[@clementjong9109]

ww teacher made me watch

[@TeamProsperity]

count 14.41 10 children? OMG 😱😱 you do know what causes that right? 🤣🤣🤣🤣🤣 Just kidding 👍

[@RobCosmanWoodworking]

The cold Canadian winters !

[@Christopher-pf8qt]

Did you say TEN children????!!

[@RobCosmanWoodworking]

six girls, four boys, same wife.

[@jeffreycunningtown5730]

I started with woodglut plans.

[@fawcusfitness]

Great video! Thanks!