Totally agree, If the c channel is not slotted though then it is not going to move, so if someone goes that rout, then no need for extra space on each side.
@@huds-onwoodworkinginc.2019 All due respect, but no that's not true. Always, ALWAYS, extend your routed C-channel mortise at least 1/4" beyond each end of C-channel length. Average range of wood movement across grain is 1/8" or more, depending on species. I guarantee you'd find pressure dents in the wood at the ends of the mortise where the metal ends of the C-channel were in contact. This turned the C-channel into a compression strut - like post & beam in a vertical structure or a doorway pull-up bar. Your friend 5-6 months ago most likely had the heat on throughout the Winter, (low humidity & warmth = wood kiln = shrinkage). Your wood span had nowhere to go but relieve itself at it's weakest point in the middle. Your screws - in slots or not = irrelevant. All they did was hold the channel in place while it did it's evil work at the ends. Good luck. I sincerely wish you well in your endeavor.
@@huds-onwoodworkinginc.2019 alspach is right. You must extend past. If there are no elongated slots, all the stress of movement is put on the screws to hold the wood movement which is why the screws were bent
@@jalspach9215 I agree . And the wood was no way dry enough to start with . There is also a glue issue , the wood should have split before the glue failed .
Yes, I concur, i.e. this is exactly what happened. Look at the end of his C Channels (no space for channel to grow in length). The metal lengthened in the warm room and popped the table apart at a laminated edge. I have never used C Channel and I have never had a top warp.
I'm subscribing today for one reason: you've replied to every comment except for those that are less than a week old. I appreciate the work you're putting into the videos. I'll be double checking my slots because of this
C channel is fine to use for this purpose if done properly. For a table top, I use one C channel about 3 inches in from the ends, and one in the middle of the table, for a maximum of 3 pieces. You used at least 6 C channels from what I could see, maybe even more than that. That could have easily been a contributing factor in this failure. The holes, actually slots, for your screws need to be about an inch and a half wide, and then set the insert and screw at the center of each slot. ALL of the screws/bolts (whichever you use) should be snug, not maxed out tight. As others have said here, make the grooves for your C channel a bit longer to allow for movement. This will prevent another failure in the future.
Great lesson. Thanks for being brave enough to share it. Whether it is C-channel, angle iron, breadboard ends, wood battens... They all need only be anchored securely in the center and the farther out from the center a fastener gets, the more movement it has to be able to have. This includes the very ends, the slot/recess has to allow room to not run into the end of the batten.
Just found your channel and I am impressed with your honesty and having the integrity to admit mistakes plus replying to all comments . I am now a subscriber
Thanks, John. I make lots of mistakes. The key is being good at fixing them. also, avoid making the same mistake twice. If I can help some of you make fewer mistakes or fix them easier, then I consider that a win.
Glad I found this video!! I'm going to be building a round table for my Mother using some Chestnut that her Father had milled 60 years ago and it's been sitting in her garage since he passed away. I'm planning to use C-Channel on the bottom to keep it all flat when it gets moved indoors (might actually move the wood indoors for a while before working with it).. Now I know to extend the slot for the C-Channel beyond the end of the metal and to use slots in the C-Channel itself where the bolts connect it to the table. Thank you for sharing your experience!
Sounds like a very special project. If you are able to bring the wood you are going to use indoors for 2 weeks or so before you use it, that will definitely help to stabilize the lumber. C channel will then just be extra protection. Good luck with the project! happy my experience could help you out. Cheers
Thanks for this real world example of wood movement. It's hard to conceptualize until you see it. A long time ago I learned the lesson on wood movement when I glued and screwed a table top down to the skirt and the expansion blew apart tenons on the frame.
Great tip!! First time using c channel on a table and glad i found your video. We are a small local woodworking and lumber supply shop in the Alliston area called Earthwood Elements. Great video!! Thank you!!!
I’m planning on making a table that’s 36x60 with live edge on the outside boards. The boards being 6 inches I wasn’t planning on using c channels do you think it’s really necessary to use them? The thickness of the table will be 1 1/2
I custom fabricate channel stabilizers as well as table legs for a living. Random, I know. The slotted method is definitely the way to go. For mitigating environments where you get extreme temperature shifts / and changes in humidity... the best way to go about stabilizing the slab is using a low viscosity resin like a casting resin as your initial seal coat. Poly's are good but a hand layup with a casting resin on all surfaces before final sand will essnetially lock the slabs MC in place. Obviously the MC will change but at a much slower rate. I like low viscosity resins because when you lay up with them, they abosrb into the wood like water which means they will get excellent penetration. You also get the added benefit of the slab having a little extra depth and pop when applying your clear if you use this method. Great work, looks like a beautiful slab.
I have seen a number of Japanese craftsmen make large tables and they always use a tapered dovetailed stringer below to keep the table top flat , no glue . Presume this allows the top to move freely without opening up at the joints. What is also critical is how much you tighten the fasteners, if they are too tight and the wood cannot move , you will have the same problem, slotted or not. One solution is to snug up the bolts and use a drop of thread lock to prevent them from coming loose or use spring washer that will maintain tension.
@@huds-onwoodworkinginc.2019 Yeah I didn't even think about that. They were fairly tight in the slots. Great info in your video documenting what happened.
Did you finish it on the other side? I can’t tell from the video, but if the bottom is unfinished and the top is, that will lead to chaos with the movement of the piece
Right off the bat without finishing the video the screw holes on the c channel need to be slotted to allow for movement, if it’s got no where to go the wood will either bend metal or crack itself
This is basically the same lesson that you'd learn making your first table with breadboard ends. You have to allow for the expansion of the wood side to side.
Interesting. Thanks for sharing. I have a redwood slab 4'x12' by 4 inches thick that was given to me. Been outside drying for 3 years. Unfortunately it has curvature in that the middle is maybe an an inch. No cupping really just bowed. The easy way out would be to cut it in half. But i would really like to straighten it. Ive had it in open air all winter will 300 pounds on center. Seems to be holding arc. Thinking of cutting grooves on short side to relieve tension or maybe groove long side then pour epoxy in with ahrinkage of epoxy maybe straighten out. Given size wetting and drying seem difficult. Any thoughts? I have a cabin that is not clumate controlled that it will be going in.
I have tried before and been successful before with the following method. You put the crown of the bow up in the air. Then set up a fan to blow air over the board. hopefully, the air movement will dry that side of the board faster than the other and counter act the initial bowing. Let me know how it goes. Good Luck!!
Could c channels cause the edges to cup ? I installed c channels on a conference table and they didn’t quite cover true edges and the edges started to cup….
hmm. I have never herd of that. was the lumber properly dried and acclimated before used for the project. I usually inset my channel 2-5 inches in from edge of table. depending on size of table and size of boards used.
Wood was kiln dried, around 8 percent. but I think you are mostly right. The house this table was in was overly dry. so dry the client has to put on moisturizer multiple times a day. So they probably need a humidifier in their house and yah the table probably shrunk because it was not acclimated for conditions that were so dry.
@@huds-onwoodworkinginc.2019 did you meter it yourself or is that what the supplier said? If you haven't invest in a good moisture meter and check your boards before using. I've found boards at my hard wood dealer that were in the mid to high 20s before, that just came from the Kiln.
Good lessons here. I'm building my first table and got the concept 13 channels, inserts/screws from KJP select hardwoods here in the states. They don't sell the nice bundle like C13 or a router jig but you save on shipping from canada.
This is a great video. I just installed some C Channel and made sure to get some with slotted holes. That will be my next build video on my channel. Couldn't find any legs that had slotted holes though.
Glad you liked it. I have had tough time finding slotted legs as well, just last week I spoke with the company who makes the legs for me. They have agreed to make all our table legs slotted from now on. Advantage of working with smaller local shops. Maybe you could ask wherever you get your legs from if the could slot them for you.
Nice! Finally an actual video on how things can go wrong. My first view from ya'll. Give me more of your mistakes. I am s subscriber! I am thinking Temperature and Altitude Changes. Canada is cold I am betting your shop is not. Now you have some beautiful wood for really nice benches.
Thanks for subscribing. I think there is often more to learn from our mistakes than our successes. So we will do our best to share both our successes and failures.
MAKE SURE C-CHANNEL BARS HAVE SLOTTED HOLES FOR SCREWS... THIS WILL ALLOW FOR EXPANSION.. PLUS, ROUTE OUT AN ADDITIONAL 1/2" OF SLOT FOR THE C-CHANNEL ON BOTH ENDS TO ALLOW FOR CONTRACTION/EXPANSION..
It looks like and sounds like the wood was not dry enough for this build. I’ve built projects with wood that was not dry enough and had similar problems.
The wood was dry, 8 percent, but the clients house was dryer. lol . So, yes you are right, for this house the lumber should have been dried to a lower moisture content.
Thank you for sharing your experience on this subject. Could you please let me know what size and thickness the C channels that you use are? Many thanks, Joe.
I now order mine from Rob at Concept Thirteen. His shop store is local to me but they also ship. there are dimensions for their channel here -> conceptthirteen.ca/collections/c-channel/products/c-channel
Having just watched your video, I hunted around and found end-mill or slot-mill bits - like a drill bit but they cut sideways. Just purchased on eBay a 6mm (1/4") bit, which seem to be standard hole size on the leg mounting plates, and will give it a try with my hand-held drill. Gotta be better than trying to mill it out with a standard drill bit! I got one for £10 Sterling, about $17 Canadian - worth a shot for that price! Thanks for the upload, have sub'ed.
A better option would be a die grinder. You can get a dirt cheap pneumatic one from harbor freight and cheap carbide bits on Amazon. Another alternative would be a dremel with a drum sanding/ cut off wheel attachment. Both do the job extremely well and fast, definitely more efficient than trying to use an end mill in a hand drill, good luck
I purchased this C Channel from Bidwell. The Channel flexes very easily thus not providing any stability to my wood project. I would purchase a sturdier channel elsewhere if you need stability.
the guys at concept thirteen have a good product. very stiff and they ship if you need. --> conceptthirteen.ca/collections/c-channel/products/c-channel
C channel is ment to be secured to the table with a slot in the c channel wide enough for the bolts to move and when secured to table enough room at end of c channel ends to allow channel to move freely also bolts shouldn't be tight. Just tight enough to hold channel to table to allow it to move in the c channel.
Exactly! Enlarged wholes with undersize bolts/ screws might not provide enough of the required space for movement and you could end up with table like mine(2 half tables... lol).
I have used non-Box store wood for years. Here's my take on your problem. I noticed a big difference in the wood grain in the bottom of the table. I think there are too many poor quality boards with way too much pith in them. Stay away from boards that were milled too close to the center of the tree.
My guess is that the humidity difference between your shop and your buddy's house was too much for the table. Winter months can get super dry especially if you are running a heater, so your stock most definitely shrunk and a lot. Movement is also affected by the type of finish and how you apply (top and underside). I found polyurethane to be very good as it seals the wood as it were inside a plastic bag, helping to keep the moisture level in the wood very stable.
I don’t understand how the c channel allows for the wood to expand and contract. I could understand if you routed out t slots in the wood and slid the bolts in then connect them to the channel. Then they would be able to move but to have the bolts going directly in with a rigid channel seems to negate the desired movement. New to woodworking but do engineering so leant make sense.
The idea is to prevent cupping, which is common issue with live edge or large board table tops, to by stiffing the underside of table with channel we can resist movement in that direction. lesson learned in this video, is that we want to make sure we still allow the wood to expand in contract along its width.
when attaching a rigid piece across the grain - be it a breadboard end, table base, or c-channel, you must allow for grain movement. In the case of c-channel, the solution is slotted holes in the c-channel.
Wood moves, metal doesn't. Extend groves in wood & oblong all holes other than center in bracket. Also a plastic washer helps under screws that will move in oblong holes. Tighten screws with plastic washers & then back them off enough to eliminate resistance for movement..
Actually metal moves too, with temperature. So if your house is very dry and you need the heat on; the wood will shrink towards the center and the metal will expand in the opposite direction, doubling the problem and possibly pulling the wood apart. Having the table near a heat source (EG an open fireplace or radiator) would not help either....
The unfortunate outcome was predictable. How much movement you get is partly determined by your finish. I see some are completely imbedding square steel tubing within epoxy in tables totally finish coated with epoxy. They use no screws, just epoxy. I think that is risky but would like to hear from others on experience with this.
So, this whole long video can be summed up in a very short explanation.. First, wood moves. Second, you need to allow for that movement Third, elongate the holes in the channel Fourth, make sure the pocket for the channel extends past each end of the channel, to allow for that movement. Way too long of a video for a VERY simple explanation and correction.
Also, note: I heard NOTHING about the moisture content of the wood in the duration of this video. Moisture content is KEY! Dry your wood properly, or you WILL have problems!
@@charlieodom9107 Excellent observation. Amazing how many do "the ostrich" on moisture content. One commenter suggested the extended "pocket" imperative months ago & he responded, politely rejecting it. Instead, remained obsessed on screws, slots & threaded inserts. But the irony of another lucid comment put out a deck-sweeping perspective that even I overlooked. Such a butcher-block style build would be warp/cup stable enough not to need C-channel at all. Simple & brilliant! KISS principle again! Also: Here on Hawaii's Big Island (for 30 years = access to incredible tropical hardwood slabs), my shop is @ 1200' elev. & wet. Here one can drive through 7+ different climate zones in 20 minutes - add to that the high-end homes/estates these works end up in. Environmental extremes - from months of A/C climate control to extended periods of open-air (Indo-Pacific architecture) = high humidity & air borne ocean salt brine. I'm constantly called in to fix such preventable disasters. If I had a dime every time I muttered to myself, "WTF?!!" Much of it really basic like sealing/finish coating EVERYTHING to encourage uniform movement. Especially undersides & relief routing where nobody sees. Too many obsess on the esthetics of presentation/visual impact. YES, by all means we want the wood to speak for itself. Too many shallow & exploitative hackers here relying on this alone. Some have become big names here. Get the Koa out the door! Perhaps I shouldn't complain. For decades I've made my shop nut ($$) on their irresponsible (or willfully ignorant/arrogant) greedy legacy. But I've never been comfortable with such repairs. Makes my stomach churn. I'm still asked at gatherings (20 years later!) how I managed to sell an award winning inlaid mini highboy the size of a night stand for $10K?? Too many stare at their shoes when I mention I never start my projects with a $$ goal. I'm obsessed with the form & function of a work of art through & through. The difference? To me the material begs/demands so much more, "Don't trash my unique beauty...please help me get there with the respect & heirloom quality I, and my admirers deserve." I'm an artist 1st & business man 2nd. Lifetime ADDHD/Dyslexia = feast & famine for me @ 62. Why I can/will never retire. I you strive for perfect, second best is still excellent. I understand the anomaly/dichotomy of extremes here. I respect those who get it & agree to meet me in the middle somewhere. Cheers & Aloha, Charlie.
@@jalspach9215 I live in Florida, and the humidity is horrible for wood. Most of the tables I build I acclimate inside my house at 50% or so humidity before selling to see if they are going to move. Construction grade lumber is pretty much useless, so unless you are building a rocking chair or abstract art, you can guarantee it will look like hammered out dog shit in short time!
@@charlieodom9107 Ah you made me laugh my friend! "hammered dog shit" term has been a go-to for years! I morphed it a bit over 20 years ago when I started seeing so much blasted apart outdoor teak furniture & self destructing "day-old-antiques" from Bali & China. "Indonesian Dog Shit" I call it. Most of the material green from the forest or plantation - goes straight into production due to demand. Proper joinery techniques left when the Dutch were run off. Willy-nilly slop joints look like the were done by Stevie Wonder with a one tooth Skilsaw -filled with color matched pulp which holds up just long enough to sell.... Many folks shocked to learn much of it's not worth fixing. Sure you've seen the same. I know Florida well. 1st live-aboard Dive Master job at 19 was out of Nassau, Bahamas, home base was back @ Ft. Lauderdale every 3-4months. That was 1980 - 83. Cheers
@Charlie Odom I may of not explained in this video, but the client had told me there house was extremely dry, he and his family have to put moisturizer on multiple times a day, The wood was dry to 9% which is usually adequate for the region in which we are located. Not dry enough for an environment as dry as this clients house though clearly. Either way, if the c channel would have be installed properly the table should be able to adjust to new environment wether it is humid or dry. The idea is that you need to account for that moment no matter what
I gave up less than halfway through waiting to hear why the c channel snapped the table in half. Way too much unnecessary detail, e.g. your client was a good buddy who you got concussion with playing football etc etc. I'll move on and take a guess it was because the wood movement was inhibited.
I would recommend extending the grove past the end of the c channel half an inch. Slots can’t move if the end of the channel can’t move in the wood.
Totally agree, If the c channel is not slotted though then it is not going to move, so if someone goes that rout, then no need for extra space on each side.
@@huds-onwoodworkinginc.2019 All due respect, but no that's not true. Always, ALWAYS, extend your routed C-channel mortise at least 1/4" beyond each end of C-channel length. Average range of wood movement across grain is 1/8" or more, depending on species. I guarantee you'd find pressure dents in the wood at the ends of the mortise where the metal ends of the C-channel were in contact. This turned the C-channel into a compression strut - like post & beam in a vertical structure or a doorway pull-up bar. Your friend 5-6 months ago most likely had the heat on throughout the Winter, (low humidity & warmth = wood kiln = shrinkage). Your wood span had nowhere to go but relieve itself at it's weakest point in the middle. Your screws - in slots or not = irrelevant. All they did was hold the channel in place while it did it's evil work at the ends. Good luck. I sincerely wish you well in your endeavor.
@@huds-onwoodworkinginc.2019 alspach is right. You must extend past. If there are no elongated slots, all the stress of movement is put on the screws to hold the wood movement which is why the screws were bent
@@jalspach9215 I agree . And the wood was no way dry enough to start with . There is also a glue issue , the wood should have split before the glue failed .
Yes, I concur, i.e. this is exactly what happened. Look at the end of his C Channels (no space for channel to grow in length). The metal lengthened in the warm room and popped the table apart at a laminated edge. I have never used C Channel and I have never had a top warp.
I'm subscribing today for one reason: you've replied to every comment except for those that are less than a week old. I appreciate the work you're putting into the videos. I'll be double checking my slots because of this
Thank you Peyton!
C channel is fine to use for this purpose if done properly. For a table top, I use one C channel about 3 inches in from the ends, and one in the middle of the table, for a maximum of 3 pieces. You used at least 6 C channels from what I could see, maybe even more than that. That could have easily been a contributing factor in this failure. The holes, actually slots, for your screws need to be about an inch and a half wide, and then set the insert and screw at the center of each slot. ALL of the screws/bolts (whichever you use) should be snug, not maxed out tight. As others have said here, make the grooves for your C channel a bit longer to allow for movement. This will prevent another failure in the future.
Glad you found a method that works for you.
I wish more youtube woodworkers would show us their mistakes. They should be embraced because we get to know the whys behind things a little better.
Great lesson. Thanks for being brave enough to share it. Whether it is C-channel, angle iron, breadboard ends, wood battens... They all need only be anchored securely in the center and the farther out from the center a fastener gets, the more movement it has to be able to have. This includes the very ends, the slot/recess has to allow room to not run into the end of the batten.
Exactly. lesson learned. Respect the movement. lol
Just found your channel and I am impressed with your honesty and having the integrity to admit mistakes plus replying to all comments . I am now a subscriber
Thanks, John. I make lots of mistakes. The key is being good at fixing them. also, avoid making the same mistake twice. If I can help some of you make fewer mistakes or fix them easier, then I consider that a win.
Glad I found this video!! I'm going to be building a round table for my Mother using some Chestnut that her Father had milled 60 years ago and it's been sitting in her garage since he passed away. I'm planning to use C-Channel on the bottom to keep it all flat when it gets moved indoors (might actually move the wood indoors for a while before working with it).. Now I know to extend the slot for the C-Channel beyond the end of the metal and to use slots in the C-Channel itself where the bolts connect it to the table.
Thank you for sharing your experience!
Sounds like a very special project. If you are able to bring the wood you are going to use indoors for 2 weeks or so before you use it, that will definitely help to stabilize the lumber. C channel will then just be extra protection. Good luck with the project! happy my experience could help you out.
Cheers
Thanks for this real world example of wood movement. It's hard to conceptualize until you see it. A long time ago I learned the lesson on wood movement when I glued and screwed a table top down to the skirt and the expansion blew apart tenons on the frame.
I have a table i made in high school that did the same thing. You live and you learn. Glad you enjoyed the video
Great tip!! First time using c channel on a table and glad i found your video. We are a small local woodworking and lumber supply shop in the Alliston area called Earthwood Elements. Great video!! Thank you!!!
I’m planning on making a table that’s 36x60 with live edge on the outside boards. The boards being 6 inches I wasn’t planning on using c channels do you think it’s really necessary to use them? The thickness of the table will be 1 1/2
Can you put C channels the long way on the table? How come only putting them to prevent cupping? How do you prevent warp the long way?
I custom fabricate channel stabilizers as well as table legs for a living. Random, I know. The slotted method is definitely the way to go. For mitigating environments where you get extreme temperature shifts / and changes in humidity... the best way to go about stabilizing the slab is using a low viscosity resin like a casting resin as your initial seal coat. Poly's are good but a hand layup with a casting resin on all surfaces before final sand will essnetially lock the slabs MC in place. Obviously the MC will change but at a much slower rate. I like low viscosity resins because when you lay up with them, they abosrb into the wood like water which means they will get excellent penetration. You also get the added benefit of the slab having a little extra depth and pop when applying your clear if you use this method.
Great work, looks like a beautiful slab.
Thanks for the tip!
I have seen a number of Japanese craftsmen make large tables and they always use a tapered dovetailed stringer below to keep the table top flat , no glue . Presume this allows the top to move freely without opening up at the joints. What is also critical is how much you tighten the fasteners, if they are too tight and the wood cannot move , you will have the same problem, slotted or not. One solution is to snug up the bolts and use a drop of thread lock to prevent them from coming loose or use spring washer that will maintain tension.
Dovetail sliders is another good option. only means you have to fill a dovetail groove in the side of the table. All good points though.
Needed to cut slots in the C-channel. It allows for a little more expansion. Seems we are constantly learning when dealing with wood.
Yes Exactly! slotted holes would have made a big difference on this one. Also longer cutout for the c channel. more space for everything... lol
@@huds-onwoodworkinginc.2019 Yeah I didn't even think about that. They were fairly tight in the slots. Great info in your video documenting what happened.
How did you bond the pieces together, glue joint seemed to fail?
So what joint is better to get the boards together
I just made a new table top for the client. ill find another use for the old table someday. or burn it... lol
Did you finish it on the other side? I can’t tell from the video, but if the bottom is unfinished and the top is, that will lead to chaos with the movement of the piece
We always Finish both sides of the table. It is probably just the poor shop lighting that makes it look like that.
If you don’t already maybe put a little blue loctite on the screws that you back out so they don’t have to be that tight but won’t come loose.
Good idea.
Right off the bat without finishing the video the screw holes on the c channel need to be slotted to allow for movement, if it’s got no where to go the wood will either bend metal or crack itself
Yup. No expansion give for the bolts.
Thank you so much for a really helpful video!
You are the real deal my friend!! Praying blessings for all of your endeavors
Glad it was helpful! Thanks for the kind words!
This is basically the same lesson that you'd learn making your first table with breadboard ends. You have to allow for the expansion of the wood side to side.
Interesting. Thanks for sharing.
I have a redwood slab 4'x12' by 4 inches thick that was given to me. Been outside drying for 3 years. Unfortunately it has curvature in that the middle is maybe an an inch. No cupping really just bowed. The easy way out would be to cut it in half. But i would really like to straighten it. Ive had it in open air all winter will 300 pounds on center. Seems to be holding arc.
Thinking of cutting grooves on short side to relieve tension or maybe groove long side then pour epoxy in with ahrinkage of epoxy maybe straighten out.
Given size wetting and drying seem difficult.
Any thoughts? I have a cabin that is not clumate controlled that it will be going in.
I have tried before and been successful before with the following method. You put the crown of the bow up in the air. Then set up a fan to blow air over the board. hopefully, the air movement will dry that side of the board faster than the other and counter act the initial bowing. Let me know how it goes. Good Luck!!
Do you have a drill press and a file? Why not make your own?
that is a good solution for come people as well.
Could c channels cause the edges to cup ? I installed c channels on a conference table and they didn’t quite cover true edges and the edges started to cup….
Dont they recommend staying 3” from the edges ?
hmm. I have never herd of that. was the lumber properly dried and acclimated before used for the project. I usually inset my channel 2-5 inches in from edge of table. depending on size of table and size of boards used.
I think that is probably a good rule of thumb!
Gonna be honest here, what was the moisture content of the wood before assembly. Once it goes into a house with low humidity, it will shrink.
Wood was kiln dried, around 8 percent. but I think you are mostly right. The house this table was in was overly dry. so dry the client has to put on moisturizer multiple times a day. So they probably need a humidifier in their house and yah the table probably shrunk because it was not acclimated for conditions that were so dry.
@@huds-onwoodworkinginc.2019 did you meter it yourself or is that what the supplier said? If you haven't invest in a good moisture meter and check your boards before using. I've found boards at my hard wood dealer that were in the mid to high 20s before, that just came from the Kiln.
Good lessons here. I'm building my first table and got the concept 13 channels, inserts/screws from KJP select hardwoods here in the states. They don't sell the nice bundle like C13 or a router jig but you save on shipping from canada.
Wishing you all the best for your up coming project!
This is a great video. I just installed some C Channel and made sure to get some with slotted holes. That will be my next build video on my channel. Couldn't find any legs that had slotted holes though.
Glad you liked it. I have had tough time finding slotted legs as well, just last week I spoke with the company who makes the legs for me. They have agreed to make all our table legs slotted from now on. Advantage of working with smaller local shops. Maybe you could ask wherever you get your legs from if the could slot them for you.
@@huds-onwoodworkinginc.2019 11:18
loved you in Pursuit of Happyness!
Thank you.
@@huds-onwoodworkinginc.2019 lol. Good video man. Keep it up!
Nice! Finally an actual video on how things can go wrong. My first view from ya'll. Give me more of your mistakes. I am s subscriber!
I am thinking Temperature and Altitude Changes. Canada is cold I am betting your shop is not. Now you have some beautiful wood for really nice benches.
Thanks for subscribing. I think there is often more to learn from our mistakes than our successes. So we will do our best to share both our successes and failures.
MAKE SURE C-CHANNEL BARS HAVE SLOTTED HOLES FOR SCREWS... THIS WILL ALLOW FOR EXPANSION.. PLUS, ROUTE OUT AN ADDITIONAL 1/2" OF SLOT FOR THE C-CHANNEL ON BOTH ENDS TO ALLOW FOR CONTRACTION/EXPANSION..
It looks like and sounds like the wood was not dry enough for this build. I’ve built projects with wood that was not dry enough and had similar problems.
The wood was dry, 8 percent, but the clients house was dryer. lol . So, yes you are right, for this house the lumber should have been dried to a lower moisture content.
Thank you for sharing your experience on this subject.
Could you please let me know what size and thickness the C channels that you use are?
Many thanks, Joe.
I now order mine from Rob at Concept Thirteen. His shop store is local to me but they also ship. there are dimensions for their channel here ->
conceptthirteen.ca/collections/c-channel/products/c-channel
I just ordered c-channels and hardware from Bidwell Wood and Iron. They are online.
thanks for sharing this lesson learned
Glad I could help!
Thanks for the tips. Great video.
Thank you. Glad you found it informative.
Having just watched your video, I hunted around and found end-mill or slot-mill bits - like a drill bit but they cut sideways. Just purchased on eBay a 6mm (1/4") bit, which seem to be standard hole size on the leg mounting plates, and will give it a try with my hand-held drill. Gotta be better than trying to mill it out with a standard drill bit! I got one for £10 Sterling, about $17 Canadian - worth a shot for that price! Thanks for the upload, have sub'ed.
Let me know how it goes!
A better option would be a die grinder. You can get a dirt cheap pneumatic one from harbor freight and cheap carbide bits on Amazon. Another alternative would be a dremel with a drum sanding/ cut off wheel attachment. Both do the job extremely well and fast, definitely more efficient than trying to use an end mill in a hand drill, good luck
I purchased this C Channel from Bidwell. The Channel flexes very easily thus not providing any stability to my wood project. I would purchase a sturdier channel elsewhere if you need stability.
the guys at concept thirteen have a good product. very stiff and they ship if you need. --> conceptthirteen.ca/collections/c-channel/products/c-channel
thank you . wow
You're most welcome
Thanks! Good luck ::) nice work, learning aside.
Thank you!
That’s unfathomable movement! Are you sure the lumber was dry?
It was definitely dry. Not dry enough for an overly dry house most likely.
C channel is ment to be secured to the table with a slot in the c channel wide enough for the bolts to move and when secured to table enough room at end of c channel ends to allow channel to move freely also bolts shouldn't be tight. Just tight enough to hold channel to table to allow it to move in the c channel.
Exactly! Enlarged wholes with undersize bolts/ screws might not provide enough of the required space for movement and you could end up with table like mine(2 half tables... lol).
Great video!
Glad you enjoyed it Matt! Hope I did the story justice.
It’s because you had no allowance for movement in the C-channel. Holes should have been elongated.
Agreed. I come to the same conclusion. more space could have also been left on each end of the channel.
I have used non-Box store wood for years. Here's my take on your problem. I noticed a big difference in the wood grain in the bottom of the table. I think there are too many poor quality boards with way too much pith in them. Stay away from boards that were milled too close to the center of the tree.
These are good theories, could be right.
My guess is that the humidity difference between your shop and your buddy's house was too much for the table. Winter months can get super dry especially if you are running a heater, so your stock most definitely shrunk and a lot. Movement is also affected by the type of finish and how you apply (top and underside). I found polyurethane to be very good as it seals the wood as it were inside a plastic bag, helping to keep the moisture level in the wood very stable.
Agreed. Thanks for the tip and input!
I don’t understand how the c channel allows for the wood to expand and contract. I could understand if you routed out t slots in the wood and slid the bolts in then connect them to the channel. Then they would be able to move but to have the bolts going directly in with a rigid channel seems to negate the desired movement. New to woodworking but do engineering so leant make sense.
The idea is to prevent cupping, which is common issue with live edge or large board table tops, to by stiffing the underside of table with channel we can resist movement in that direction. lesson learned in this video, is that we want to make sure we still allow the wood to expand in contract along its width.
when attaching a rigid piece across the grain - be it a breadboard end, table base, or c-channel, you must allow for grain movement. In the case of c-channel, the solution is slotted holes in the c-channel.
Thanks for sharing for experience with your tabletop build. Blacktail Studios is a master with large slabs and using slotted C-channel.
First thing to see in couple first second, no elongated holes :(
Wood moves, metal doesn't. Extend groves in wood & oblong all holes other than center in bracket. Also a plastic washer helps under screws that will move in oblong holes.
Tighten screws with plastic washers & then back them off enough to eliminate resistance for movement..
All Great points! Thanks for contributing these ideas.
Actually metal moves too, with temperature. So if your house is very dry and you need the heat on; the wood will shrink towards the center and the metal will expand in the opposite direction, doubling the problem and possibly pulling the wood apart. Having the table near a heat source (EG an open fireplace or radiator) would not help either....
@@PeterHoltYes, technically metal moves, but with this situation, for all practical purposes, it doesn't..
The unfortunate outcome was predictable. How much movement you get is partly determined by your finish. I see some are completely imbedding square steel tubing within epoxy in tables totally finish coated with epoxy. They use no screws, just epoxy. I think that is risky but would like to hear from others on experience with this.
Easier and prettier to use a sliding dovetail
That is also a great option. Just means the slot will be visible from the side of table or have to be patched.
That’s a crap ton of shrinkage…
Must have been in the pool.
Something like that. lol
Good video, thanks for sharing. Maybe less scratching your head in future videos ;)
lol. I will make note to de lice before filming the next video.
@@huds-onwoodworkinginc.2019 7:51 is my fav scratch!
I appreciate the example of it cracking but dude there’s way too many details in here that don’t matter.
Well thanks for the feedback. feel free to cut out all those details and send the video back to me. Ill post your video instead,
Troll
So, this whole long video can be summed up in a very short explanation..
First, wood moves.
Second, you need to allow for that movement
Third, elongate the holes in the channel
Fourth, make sure the pocket for the channel extends past each end of the channel, to allow for that movement.
Way too long of a video for a VERY simple explanation and correction.
Also, note: I heard NOTHING about the moisture content of the wood in the duration of this video. Moisture content is KEY! Dry your wood properly, or you WILL have problems!
@@charlieodom9107 Excellent observation. Amazing how many do "the ostrich" on moisture content. One commenter suggested the extended "pocket" imperative months ago & he responded, politely rejecting it. Instead, remained obsessed on screws, slots & threaded inserts. But the irony of another lucid comment put out a deck-sweeping perspective that even I overlooked. Such a butcher-block style build would be warp/cup stable enough not to need C-channel at all. Simple & brilliant! KISS principle again!
Also: Here on Hawaii's Big Island (for 30 years = access to incredible tropical hardwood slabs), my shop is @ 1200' elev. & wet. Here one can drive through 7+ different climate zones in 20 minutes - add to that the high-end homes/estates these works end up in. Environmental extremes - from months of A/C climate control to extended periods of open-air (Indo-Pacific architecture) = high humidity & air borne ocean salt brine. I'm constantly called in to fix such preventable disasters. If I had a dime every time I muttered to myself, "WTF?!!" Much of it really basic like sealing/finish coating EVERYTHING to encourage uniform movement. Especially undersides & relief routing where nobody sees. Too many obsess on the esthetics of presentation/visual impact.
YES, by all means we want the wood to speak for itself. Too many shallow & exploitative hackers here relying on this alone. Some have become big names here. Get the Koa out the door! Perhaps I shouldn't complain. For decades I've made my shop nut ($$) on their irresponsible (or willfully ignorant/arrogant) greedy legacy. But I've never been comfortable with such repairs. Makes my stomach churn. I'm still asked at gatherings (20 years later!) how I managed to sell an award winning inlaid mini highboy the size of a night stand for $10K?? Too many stare at their shoes when I mention I never start my projects with a $$ goal. I'm obsessed with the form & function of a work of art through & through. The difference? To me the material begs/demands so much more, "Don't trash my unique beauty...please help me get there with the respect & heirloom quality I, and my admirers deserve." I'm an artist 1st & business man 2nd. Lifetime ADDHD/Dyslexia = feast & famine for me @ 62. Why I can/will never retire. I you strive for perfect, second best is still excellent. I understand the anomaly/dichotomy of extremes here. I respect those who get it & agree to meet me in the middle somewhere. Cheers & Aloha, Charlie.
@@jalspach9215 I live in Florida, and the humidity is horrible for wood. Most of the tables I build I acclimate inside my house at 50% or so humidity before selling to see if they are going to move. Construction grade lumber is pretty much useless, so unless you are building a rocking chair or abstract art, you can guarantee it will look like hammered out dog shit in short time!
@@charlieodom9107 Ah you made me laugh my friend! "hammered dog shit" term has been a go-to for years! I morphed it a bit over 20 years ago when I started seeing so much blasted apart outdoor teak furniture & self destructing "day-old-antiques" from Bali & China. "Indonesian Dog Shit" I call it. Most of the material green from the forest or plantation - goes straight into production due to demand. Proper joinery techniques left when the Dutch were run off. Willy-nilly slop joints look like the were done by Stevie Wonder with a one tooth Skilsaw -filled with color matched pulp which holds up just long enough to sell.... Many folks shocked to learn much of it's not worth fixing. Sure you've seen the same. I know Florida well. 1st live-aboard Dive Master job at 19 was out of Nassau, Bahamas, home base was back @ Ft. Lauderdale every 3-4months. That was 1980 - 83. Cheers
@Charlie Odom I may of not explained in this video, but the client had told me there house was extremely dry, he and his family have to put moisturizer on multiple times a day, The wood was dry to 9% which is usually adequate for the region in which we are located. Not dry enough for an environment as dry as this clients house though clearly. Either way, if the c channel would have be installed properly the table should be able to adjust to new environment wether it is humid or dry. The idea is that you need to account for that moment no matter what
fill the gap with some new epoxy and call it good.
I gave up less than halfway through waiting to hear why the c channel snapped the table in half. Way too much unnecessary detail, e.g. your client was a good buddy who you got concussion with playing football etc etc. I'll move on and take a guess it was because the wood movement was inhibited.
I guess you will never know...
You did it wrong
Yes, This is the point of the video. To point out what I did wrong on this one. Thanks for your constructive feedback!