As a finish carpenter I go through a lot of sand paper, just ordered 2 bundles. I have never seen this before glad you are keeping it alive, good luck with the new endeavor I’ll support as I can
Funny but true C-channel story. We have a rustic outdoor patio trestle table I built out of recycled pallet wood. My cousin got drunk, jumped up on the table and snapped it in half. 🤪 I fixed it by reinforcing with two 3" C-Channels coated with bridge primer running lengthwise. It's now drunkard proof. 👍
Something that people don't think about when installing c-channel is that they may be helping the table resist cupping/crowning along the width, but they are increasing the amount of sag along the woods length by severing the wood fibres on the bottom of the board. Say you recess that channel 1/2" on something that's 1-1/2" thick and you toss c-channel on either end and in the middle. Well you've now got the weight of an 1-1/2" thick top with the sag resistance (along the length) of only a 1" thick table. In addition, to actually have enough bending resistance to keep a large top flat, you'd need such a tall channel that you'd need to just bolt it to the bottom upside down because it's too tall to recess. Massive waste of time.
Even slab furniture didn’t regularly feature c-channel until fairly recently. I always saw it as a fastening solution to attach metal bases, as opposed to a way to keep things flat. Having properly dried, milled, and finished slabs seems like a better insurance policy for flatness than c channel attached with screws, and with glued up panels, you can add various other methods to keep things flat.
Embedding C channel has always struck me as odd. Let's cut through around 50% of the fibers that make the tabletop strong in the off chance that the table curls.
I agree with your assessment 100%... in addition to what you said, the weak link is the screws used to hold the c channel in place. Meaning, if a top decides that it wants to cup, it will pull through a couple of screws without hesitation. This happened on my kitchen table (cherry top mounted to a decorative iron base). Wood movement is a powerful force... if it wants to move, it will move.
i've never had a good use fo c-channel. i've always used sliding dovetailed cross supports because that's what i was taught and it's held up in my applications so far. it is a heavier and more labor-intensive option though.
I used C-channel with my dining table which wasn't a slab. The legs I used are from a company called TipToe and they just grip the edge of the table table. I wouldn't have been happy not using the C-channel.
I have a new respect for Marc(real marks have K’s) Matt and Shannon after listening to every wood talk while I work 10 hours a day for the last month or two. I miss Vanderlist (I spell like new matt reads) as the changes have gone quickly for me. Thanks for not quitting, quilting, knitting and giving great solid advice. I will only use a c channel on customers tops that are single slab or 18” and wider slabs joined up. Use it as an insurance policy just for safety, but wood will Do what wood wants to do.
Marc you make me laugh and educate me at the same time, WOW! What is the deal with the C Channel topic on RUclips? Marc said I don't need it, good enough for me!
A 3" piece of wood as bracing like you had on that one table is going to be at least as stiff as the c-channel you showed at the beginning of the video, and quite possibly a lot stiffer. But the question is not how stiff is the wood table top but how strong are the moisture driven warping forces. If I were really worried about a warping top I'd conceal a wrapped steel I-beam under the table.
The 3" brace is going to do far more for resistance to cupping than a c-channel ever will. Resistance to bending is all about the height of the member.
I use them on some of my MCM inspired pieces that don't utilize an apron to keep it flat--as you mentioned, a lack of structural support. On my apron-and-leg frame tables, or breadboard ends tables, I don't use them.
Thanks. I made tables without C-channel from 1970 as a teenager at school - they still look good. But, with a second hand pub table top for my daughter, I was all set to order C-channel because... all the RUclips videos use it. Back to first principles
I've never come across C-channel that was useful in a new-build situation. The wood movement is generally much stronger than that thin, soft steel can prevent. Better bet is a piece of 8/4 hard maple with a sliding dovetail if you're really concerned about cupping.
Hi Marc great video as always! Ok, so if strictly speaking of solid slab tables, where would you draw the line and use a C-channel? I have a 52" wide 8ft long solid slab dining table. I opted for c-channels in that and feel that the little extra insurance was worth the time/extra cost. Although, on something that big, I also feel like if the wood moves enough it will just bend the C-channel anyway. But what about smaller slabs like 36 inches wide or an epoxy river table 30" wide using two ten inch wide slabs and a ten inch wide river? I know this is very subjective, but I am curious if you have any hard rules or just kind of feel things out on a per project basis.
Spag’s are you procrastinating? I’m wondering who’s going to finish their big project first; you and the wife’s closet or Bourbon moth and the Airstream? I’ve followed both of you for a while, and love your work. Thanks man
I have a table in making that starts with 8/4 ash, but it’s a gaming table so I’m routing/removing large sections from the top so that I can then later fill them with removable boards so it can double as a dining table. 8 dice trays and one 30x30 square in the middle for board games. I’ll probably end up removing 1/2 to 3/4 thick of material. Thoughts on whether this varying thickness will necessitate something like C channel? Breadboards aren’t an option due to sliding cup holders (and the dice trays).
In that case I think you should opt for at least some kind of reinforcement. Once you excavate a lot of material you're really messing with the structural stability as well as promoting an uneven loss of moisture from the center of the board. So there's a high potential for movement. In your case, c-channel would probably be smart.
Thanks man, I was thinking that because of how much material I was removing, but I am only a year into the vocation so, this video came up perfect timing.
@@woodwhisperer one could argue that by evacuating said material, forces causing movement are reduced. I recall the trick to cut one or two grooves along the length of a plank’s backside. Common technique to reduce cupping. Having said all that I really have no clue. Just hearing bits and pieces and putting it together. I saw your explanation and respectfully it sounds backwards. Care to double down?
Thank you, I was wondering why my kitchen table came with metal bars on the under side. It seemed so unlikely to need it. Now I know it doesn't :) And if I was ever going to use a c-channel, I would at least make some sort of grove in the middle of the boards, to reduce the movement first. Otherwise I don't see how the c-channel would remotely have the stiffness to stop the bending.
I think it should be noted to use lumber that is near the EMC for the destination of the piece. I have a coffee table and dining table that do not have any cross grain support, no breadboard end nor no apron. They were made with lumber that was properly dried and near destination EMC. They aren't perfectly flat but the average person will never be able to tell.
I've only used c-channel once. For an outdoor patio, under cover, table top made from 2x8 SYP construction lumber from the green box store. I dont have a moisture meter, so no idea if they were properly dried. 3 years on and it hasn't moved in any noticable way. And no idea if the c-channel is even helping.
Great video. I've always been skeptical of c-channel. Unless you're going with extremely thick steel, it's going to deflect quite a lot over say, a 30" run. And wood that wants to move will exert and incredible amount of force. So c-channel really only makes sense in a case where you have a really thin top that isn't capable of much force, and no or very little in terms of support from the frame. Which is just a terrible idea all around. It seems to me that the less support you want to use, the thicker the top should be, and the thinner the top, the more it should be supported. If you get that right and can have reasonable control over your humidity, it should stay functionally flat(ish) - assuming it was milled well and dried to ~ moisture equilibrium for the intended space.
Woodworking techniques and methods have been developed and refined over thousands of years, some of the current trends (slabs/resin/etc) ignores that body of knowledge/skill and people are looking for ‘crutches’. Sometimes the crutches help sometimes they don’t . I’ll stick with the tried and true methods and avoid the fads.
Over 30 years and never used it, matter of fact never heard if it until recent years. Since most “regular woodworkers” are not making furniture that cost $THOUSANDS$ of dollars I don’t think it really matters. But that’s just an old man’s opinion!
I went to a metal shop once and ask them about purchasing C channels for an upcoming project, and after talking with the owner of the shop about what I would be using it, for he essentially said that it would go completely against what the form and function of a C channel is. He did not think it would keep anything flat when laid horizontally along the wood like woodworkers use them. They are stronger and meant to be used on their side to keep things flat and sturdy, as on trailers or other equipment where they are typically used. The strength is not along belly and your example of a failed C channel is exactly what this metal worker said would happen.
C-channels need to be sized and I have seen people add the smallest "bar size" channel and when I saw it in his shop I told him he needed to rethink bar size and number of them on the project. He had a slab for a dining room table made from, no one but two a large oak crotches and was about twelve feet long. It was a gorgeous table and he'd really done a good job, but he cut a corner and only put three to support all that. Ok, long story short, the table warped like an old vinyl record in the sunlight. The customer wasn't happy, he was doing the blame game about humidity and it was ugly to say the very least. They wound up going to court and the judge apparently had some knowledge of wood working and saw the issue and encouraged them to work it out because both parties had wood chips on their hands. I never did find out what they settled for but I can tell you he got out of the large slab table business.
I have a desk top that my dad made over 50 years ago that violated the rule on never cross glue support boards it’s still flat and I made solid wood doors with cross glue supports still flat. They are both cherry.
Im new to woodworking, and wonder when you should and should not use c channels? I bought a walnut 2inch board (1.8m x 0.5m) and I want to dip it all in epoxy, top and bottom with a river in the middle. If I should, then when? After pouring epoxy and letting cure, or before? OR when you encase the board, you wont nee it because the moisture content wil not change?
Agreed. My nearly 200 something board foot black walnut table is fine, most boards were 8 to 11" wide over 8' (or is it 9'? hmmm) long. Moisture content was at 8% at time of glue up, via pin holes and surface on multiple areas (pin holes on bottom, because I'm not a savage). The custom frame (also walnut) and skirt attached keeps it pretty straight. I think 1/8" deviation on one side, but that also could be from hand scraped wood floors, foundation settling, etc. Whatever!
I used four pieces of 3" wide "c" on a 24"x24" night stand made entirely from 1/2" Baltic Birch ply. OK, I didn't, really. I think that type of reinforcement has it's "place" in woodworking. But if you don't use it correctly and follow ALL the other requirements when woodworking, it won't matter one bit.
I’ve been woodworking for over 35 years and I’ve never used the stuff. I guess it’s just the good old fashion joinery & engineering that sits well with me. Most people don’t really study the art. So they don’t know any better. Have a good one.
how do you align the C channel if using it on a single piece of slab. Thinking of making a dining table from two pieces ( bookmatched) of black walnut or single slab. Even though it would at my home, still dont want to fix it every few years :)
If I was making a large piece for a customer, and they were already willing to pay a hefty price, and it wasn't some extra cost to me, I would put it in there as insurance, especially if they weren't local. I really do not think people care about a metal bar on the underside, and honestly non-woodworkers may even feel like it makes the table "sturdier". If it isn't an extra cost to you, and is covered by the client, why not use it? Its not a lot of extra work to put in. However, for my own tables, nah, hard pass, but I also am building panel glued tables for myself, because who the heck can pay for a large slab to have in their own home? Not me.
If the customer is paying a hefty price either way, the cost to you is the cost of materials and your additional time. You could potentially charge the exact same amount and simply make a couple hundred more on the job. Not saying you should or shouldn't....that's obviously your call, but there is absolutely a cost to you for including them.
Think of "C channel" as (for example) 2x8" lumber. For the same amount of force, pushing against the wider 8" wide edge will cause more flex than pushing against the 2" edge. Nothing magic about it.
Sorry, I meant "surface" not "edge" but you get the idea. As long as I'm here - the type of metal makes a big difference in rigidity -- I assume this "C Channel" is regular old mild steel.
I have a White Oak dining table 5' X 5, it was edge jointed using #20 buscuits 8 yrs ago with no noticable movement. I've seen a bunch of these tubers using C-channal with no need to. I think its a tuber fad are they'er not the wood worker they think they are.
I do add c-channel in large single slab pieces, or anything with epoxy. And that's because epoxy sucks. Yes I make them, but its a trashy product and i've been slowly getting away from it altogether. I do not trust any epoxy table, regardless of cure time, to hold its original shape. There is too much flex and uncertainity on how it will react with moisture, temperature and light/sunlight variations over the years. $50 insurance and an hour of my time, is most definitely worth it on commissioned pieces. Otherwise, I totally agree with everything you have touched on. One thing I would also like to add; is that not all c-channel/steel is made the same. The piece you have in your hands in the beginning is a very slight c channel. The example you showed from reddit was a slight stronger channel but again a relatively weak piece of steel (not saying it mattered in that particular case), I typically get my 2" c channel from a local steel shop and it is very heavy. I think wood forces, in the right condition, could bend it, but it is reduced even more. just my 2 cents. Cheers
I thought you were ABSOLUTELY going to say your backside was eatin' height I don't know if that means I have a dirty mind or you have a dirty mind that has infected my once-clean mind
1:51 Never wear gloves when you are working with table/miter saws, a drill press, or other fast, and strong, rotating machines!! If a glove gets caught, it will pull your hand in the blade/drill etc...
C channel¿???!!?? What the??? I have numerous tables I have made in my house and no one has ever sat down with a straight edge and assessed the top before sitting down for a meal. I don't even have to search my guests for laser levels or steel rules before entry. Never has any body complained. Remember there are only two perfect things in nature
I think you said it yourself it’s insurance. It may not be needed in a lot of cases but we also don’t need health insurance the majority of days of our life. Insurance is there for the rare times you do. The cost of using c channel is small compared to the cost of fixing a table that warps or cups. If you are making a slab table or a hardwood table the wood alone costs hundreds or thousands of dollars. The c channel and fasteners is nothing cost or time wise.
I think the better analogy here is more like an extended warranty. Will you need it? Only if the manufacturer messed something up or you have horrible luck. Which is why I usually pass on extended warranties. :)
I can see what you are saying Marc but I also think saying it’s a waste of time is also incorrect. I’ve built two tables and a desk and haven’t used c channel and I’m fine with that risk but I only build stuff for myself it my desk or kitchen tables cups 1/8 or even 1/4 of an inch it’s fine it’s still functional. For someone who makes a living making expensive custom furniture an unhappy customer with a non flat table is a much bigger issue. If I was getting paid based on my quality I would use c channel as an insurance policy every time.
Please don't use the animated head in the corner in future videos, its REALLY annoying and trying to avoid looking at it while seeing the real content gives me a headache. Like having someone keep flashing a really bright light in your eyes while trying to watch a movie at the theatre.
The problem isn't solved; the variability of the size of the banana makes your otherwise astute observation moot, and still unfactored in a factual way. Damn it, Marc @woodwhisperer. You've confused the entire universe with your shifty banana.
Thanks for this. C-channel makes sense if you're doing a slab table & just attaching hairpin metal legs to it. With more traditional wood bases, I always saw the base as part of that stabilizing structure keeping things flat.
My c channel story: Im working on a 12 ft white oak conference table (its a monster) It was flat after the glue up for a day or two but developed a 1/4+" cup in the center. I installed 4 sticks of c channel underneath and was able to get the cup down to around 1/8" (with hopes that the base adds even more stability. I could be doing something wrong but i see cupping happening often in my larger dining table builds
“Leave comments for the algorithm that I’d love to not read”. In present to you the most honest woodworking content creator in your YT. 😂 Did you leave slots in the wooden batons if your tables without c Chanel, or did those just behave well enough without that?
C channel and its use in wood has always amazed or should I say amused me! The first amazing or wait amusing thing is folks have flat stock formed into what they are calling "C Channel" which as a structural member goes it's a major NO NO! and even when your using actual C channel it is engineered to be used on edge and not flat like folks use it. the last amazing or amusing part is that the channel is attached to the slab in multiple locations with threaded inserts! Oh wait isn't the threaded inserts the weakest point? and then assuming the channel is providing support when the only strength are the short vertical portions of the channel. Ok enough! I will leave you with this thought! I believe it's been said that the interweb is a huge echo chamber! Good day
Thanks a bunch for all the tips, Marc! 😊 Yeah, I'm planning on an outdoor table and I'm considering C channels... Anyway, stay safe there with your family! 🖖😊
I've never understood those things. I mean, it you are going to all that trouble, why not go all-in on the outdated kitsch and embed a few compact discs or flip-phones?
I 100% agree. About 1 yr ago I built a farm house style table from kilm dried ash. 13.5 ft x 6 ft x 1.75 inch thick. I almost added channels iron, but Marc said in one of his earlier videos that channels are not needed to glue together, kilm dried lumber. He was right. Table is very flat. Thanks for the great advice Marc!!!!
This video was really helpful bc I was just pondering about whether C channels are helpful for large table tops made with dimensional lumber. Thanks for sharing your opinion!!
Slabs move more than boards, but it's still not even necessary. This is what happens when "woodworkers" who pour plastic on slabs start handing out free advice.
Does this C-channel idea actually work? Doesn't seem to me like it should - I mean if you took that C-channel and spanned a 3' gap, I bet it'd take less than 50# of force in the middle to deflect it 1/8". Not much more to get 1/4". If you have a 3x3 piece of wood that's 1 1/4" thick, you'll need a lot more force than that to get it to deflect 1/8". Maybe enough to break it since you're going across the grain.
Looking for my Backside....Sandpaper? Go here: backsidesandpaper.com/
International Shipping yet?
Yup.
Awwww... $56 to ship to Australia :(@@woodwhisperer
Yikes!
As a finish carpenter I go through a lot of sand paper, just ordered 2 bundles. I have never seen this before glad you are keeping it alive, good luck with the new endeavor I’ll support as I can
I love that you showed some of the older projects that aren't dead flat, makes me feel better about my dining table that is off by just a little
Funny but true C-channel story. We have a rustic outdoor patio trestle table I built out of recycled pallet wood. My cousin got drunk, jumped up on the table and snapped it in half. 🤪 I fixed it by reinforcing with two 3" C-Channels coated with bridge primer running lengthwise. It's now drunkard proof. 👍
A worthy application. :)
they will make a better drunkard
Never underestimate the power of drunkenness.
@@TaylerMade Ha! You are probably right. This takes using C-channels to prevent wood "movement" to another level.
@@kenparnell4297 That's why my two outside tables are concrete pours that I stained. There's been a drunk girl or two dancing on them. ;-)
It’s good to finally see some personality from Shannon.
Something that people don't think about when installing c-channel is that they may be helping the table resist cupping/crowning along the width, but they are increasing the amount of sag along the woods length by severing the wood fibres on the bottom of the board. Say you recess that channel 1/2" on something that's 1-1/2" thick and you toss c-channel on either end and in the middle. Well you've now got the weight of an 1-1/2" thick top with the sag resistance (along the length) of only a 1" thick table. In addition, to actually have enough bending resistance to keep a large top flat, you'd need such a tall channel that you'd need to just bolt it to the bottom upside down because it's too tall to recess. Massive waste of time.
Even slab furniture didn’t regularly feature c-channel until fairly recently. I always saw it as a fastening solution to attach metal bases, as opposed to a way to keep things flat. Having properly dried, milled, and finished slabs seems like a better insurance policy for flatness than c channel attached with screws, and with glued up panels, you can add various other methods to keep things flat.
the entertainment/education balance is on point in this one
Embedding C channel has always struck me as odd. Let's cut through around 50% of the fibers that make the tabletop strong in the off chance that the table curls.
I agree with your assessment 100%... in addition to what you said, the weak link is the screws used to hold the c channel in place. Meaning, if a top decides that it wants to cup, it will pull through a couple of screws without hesitation. This happened on my kitchen table (cherry top mounted to a decorative iron base). Wood movement is a powerful force... if it wants to move, it will move.
Thank you. I was searching through the comments to see if anyone had mentioned how it all comes down to that handful of screws and inserts.
i've never had a good use fo c-channel. i've always used sliding dovetailed cross supports because that's what i was taught and it's held up in my applications so far. it is a heavier and more labor-intensive option though.
Bingo
If Shannon’s segment was a voicemail, this video would have been 20 minutes long
I used C-channel with my dining table which wasn't a slab. The legs I used are from a company called TipToe and they just grip the edge of the table table. I wouldn't have been happy not using the C-channel.
Good information. And... LOL... "tell us all your stories in the comments... I'd love to not read them".
I have a new respect for Marc(real marks have K’s) Matt and Shannon after listening to every wood talk while I work 10 hours a day for the last month or two. I miss Vanderlist (I spell like new matt reads) as the changes have gone quickly for me. Thanks for not quitting, quilting, knitting and giving great solid advice. I will only use a c channel on customers tops that are single slab or 18” and wider slabs joined up. Use it as an insurance policy just for safety, but wood will
Do what wood wants to do.
Marc you make me laugh and educate me at the same time, WOW! What is the deal with the C Channel topic on RUclips? Marc said I don't need it, good enough for me!
A 3" piece of wood as bracing like you had on that one table is going to be at least as stiff as the c-channel you showed at the beginning of the video, and quite possibly a lot stiffer. But the question is not how stiff is the wood table top but how strong are the moisture driven warping forces. If I were really worried about a warping top I'd conceal a wrapped steel I-beam under the table.
The 3" brace is going to do far more for resistance to cupping than a c-channel ever will. Resistance to bending is all about the height of the member.
I use them on some of my MCM inspired pieces that don't utilize an apron to keep it flat--as you mentioned, a lack of structural support. On my apron-and-leg frame tables, or breadboard ends tables, I don't use them.
Thanks. I made tables without C-channel from 1970 as a teenager at school - they still look good. But, with a second hand pub table top for my daughter, I was all set to order C-channel because... all the RUclips videos use it. Back to first principles
I am pouring a river table of 6 2inch cookie slabs to make a table that is 4ft wide and 6ft long. Cross grain. Do you think I need a C channel?
I've never come across C-channel that was useful in a new-build situation. The wood movement is generally much stronger than that thin, soft steel can prevent. Better bet is a piece of 8/4 hard maple with a sliding dovetail if you're really concerned about cupping.
Perfect rendition of Shannon
Hi Marc great video as always! Ok, so if strictly speaking of solid slab tables, where would you draw the line and use a C-channel? I have a 52" wide 8ft long solid slab dining table. I opted for c-channels in that and feel that the little extra insurance was worth the time/extra cost. Although, on something that big, I also feel like if the wood moves enough it will just bend the C-channel anyway. But what about smaller slabs like 36 inches wide or an epoxy river table 30" wide using two ten inch wide slabs and a ten inch wide river? I know this is very subjective, but I am curious if you have any hard rules or just kind of feel things out on a per project basis.
Spag’s are you procrastinating? I’m wondering who’s going to finish their big project first; you and the wife’s closet or Bourbon moth and the Airstream? I’ve followed both of you for a while, and love your work. Thanks man
I have a table in making that starts with 8/4 ash, but it’s a gaming table so I’m routing/removing large sections from the top so that I can then later fill them with removable boards so it can double as a dining table. 8 dice trays and one 30x30 square in the middle for board games. I’ll probably end up removing 1/2 to 3/4 thick of material.
Thoughts on whether this varying thickness will necessitate something like C channel? Breadboards aren’t an option due to sliding cup holders (and the dice trays).
In that case I think you should opt for at least some kind of reinforcement. Once you excavate a lot of material you're really messing with the structural stability as well as promoting an uneven loss of moisture from the center of the board. So there's a high potential for movement. In your case, c-channel would probably be smart.
Thanks man, I was thinking that because of how much material I was removing, but I am only a year into the vocation so, this video came up perfect timing.
@@woodwhisperer one could argue that by evacuating said material, forces causing movement are reduced. I recall the trick to cut one or two grooves along the length of a plank’s backside. Common technique to reduce cupping. Having said all that I really have no clue. Just hearing bits and pieces and putting it together. I saw your explanation and respectfully it sounds backwards. Care to double down?
Thank you, I was wondering why my kitchen table came with metal bars on the under side. It seemed so unlikely to need it. Now I know it doesn't :) And if I was ever going to use a c-channel, I would at least make some sort of grove in the middle of the boards, to reduce the movement first. Otherwise I don't see how the c-channel would remotely have the stiffness to stop the bending.
Deliciously salty. Thanks for elucidating that, amigo!
I think it should be noted to use lumber that is near the EMC for the destination of the piece. I have a coffee table and dining table that do not have any cross grain support, no breadboard end nor no apron. They were made with lumber that was properly dried and near destination EMC. They aren't perfectly flat but the average person will never be able to tell.
I've only used c-channel once. For an outdoor patio, under cover, table top made from 2x8 SYP construction lumber from the green box store. I dont have a moisture meter, so no idea if they were properly dried. 3 years on and it hasn't moved in any noticable way. And no idea if the c-channel is even helping.
Great video. I've always been skeptical of c-channel. Unless you're going with extremely thick steel, it's going to deflect quite a lot over say, a 30" run. And wood that wants to move will exert and incredible amount of force. So c-channel really only makes sense in a case where you have a really thin top that isn't capable of much force, and no or very little in terms of support from the frame. Which is just a terrible idea all around. It seems to me that the less support you want to use, the thicker the top should be, and the thinner the top, the more it should be supported. If you get that right and can have reasonable control over your humidity, it should stay functionally flat(ish) - assuming it was milled well and dried to ~ moisture equilibrium for the intended space.
Some of Shannon's best work I must say...
He's an American treasure!
Woodworking techniques and methods have been developed and refined over thousands of years, some of the current trends (slabs/resin/etc) ignores that body of knowledge/skill and people are looking for ‘crutches’. Sometimes the crutches help sometimes they don’t . I’ll stick with the tried and true methods and avoid the fads.
Over 30 years and never used it, matter of fact never heard if it until recent years. Since most “regular woodworkers” are not making furniture that cost $THOUSANDS$ of dollars I don’t think it really matters. But that’s just an old man’s opinion!
I went to a metal shop once and ask them about purchasing C channels for an upcoming project, and after talking with the owner of the shop about what I would be using it, for he essentially said that it would go completely against what the form and function of a C channel is. He did not think it would keep anything flat when laid horizontally along the wood like woodworkers use them. They are stronger and meant to be used on their side to keep things flat and sturdy, as on trailers or other equipment where they are typically used. The strength is not along belly and your example of a failed C channel is exactly what this metal worker said would happen.
C-channels need to be sized and I have seen people add the smallest "bar size" channel and when I saw it in his shop I told him he needed to rethink bar size and number of them on the project. He had a slab for a dining room table made from, no one but two a large oak crotches and was about twelve feet long. It was a gorgeous table and he'd really done a good job, but he cut a corner and only put three to support all that.
Ok, long story short, the table warped like an old vinyl record in the sunlight. The customer wasn't happy, he was doing the blame game about humidity and it was ugly to say the very least. They wound up going to court and the judge apparently had some knowledge of wood working and saw the issue and encouraged them to work it out because both parties had wood chips on their hands.
I never did find out what they settled for but I can tell you he got out of the large slab table business.
I have a desk top that my dad made over 50 years ago that violated the rule on never cross glue support boards it’s still flat and I made solid wood doors with cross glue supports still flat. They are both cherry.
The only movement I've ever had was when FedEx managed to destroy a table I shipped. Maybe C-Channel would have helped there/s
Maybe UPS Channel...
Great video
Im new to woodworking, and wonder when you should and should not use c channels? I bought a walnut 2inch board (1.8m x 0.5m) and I want to dip it all in epoxy, top and bottom with a river in the middle.
If I should, then when? After pouring epoxy and letting cure, or before? OR when you encase the board, you wont nee it because the moisture content wil not change?
Agreed. My nearly 200 something board foot black walnut table is fine, most boards were 8 to 11" wide over 8' (or is it 9'? hmmm) long. Moisture content was at 8% at time of glue up, via pin holes and surface on multiple areas (pin holes on bottom, because I'm not a savage). The custom frame (also walnut) and skirt attached keeps it pretty straight. I think 1/8" deviation on one side, but that also could be from hand scraped wood floors, foundation settling, etc.
Whatever!
I used four pieces of 3" wide "c" on a 24"x24" night stand made entirely from 1/2" Baltic Birch ply.
OK, I didn't, really. I think that type of reinforcement has it's "place" in woodworking. But if you don't use it correctly and follow ALL the other requirements when woodworking, it won't matter one bit.
I’ve been woodworking for over 35 years and I’ve never used the stuff. I guess it’s just the good old fashion joinery & engineering that sits well with me. Most people don’t really study the art. So they don’t know any better. Have a good one.
yeah I've never thought that c channel was gonna help. The forces involved will bend c channel too.
how do you align the C channel if using it on a single piece of slab. Thinking of making a dining table from two pieces ( bookmatched) of black walnut or single slab. Even though it would at my home, still dont want to fix it every few years :)
C channel on the front and back edges of ikea cabinet shelves to keep them from bending under load.
You mentioned kiln dried wood. What about air dried wood?
Doesn't always need to be a metal C section either you can always dovetail a nice chunky strongback across the underside.
The hold my beer comment got me! 😂
I have to agree. i personally really hate using screws, since it feels unnatural. just like you wouldnt put plastics in a metal watch.
What about putting a sliding dovetail across the boards?
That's a pretty elegant solution and one that builders have used for a long time.
@@woodwhisperer hey Mark!
If I was making a large piece for a customer, and they were already willing to pay a hefty price, and it wasn't some extra cost to me, I would put it in there as insurance, especially if they weren't local. I really do not think people care about a metal bar on the underside, and honestly non-woodworkers may even feel like it makes the table "sturdier". If it isn't an extra cost to you, and is covered by the client, why not use it? Its not a lot of extra work to put in. However, for my own tables, nah, hard pass, but I also am building panel glued tables for myself, because who the heck can pay for a large slab to have in their own home? Not me.
If the customer is paying a hefty price either way, the cost to you is the cost of materials and your additional time. You could potentially charge the exact same amount and simply make a couple hundred more on the job. Not saying you should or shouldn't....that's obviously your call, but there is absolutely a cost to you for including them.
Wood can move, baby!
Stretford end?😬
Should've showed one with c channel to see if there any difference at all
What would be the point when the table tops are already flat enough?
never used one and never felt the necessity tbh 😅
Think of "C channel" as (for example) 2x8" lumber. For the same amount of force, pushing against the wider 8" wide edge will cause more flex than pushing against the 2" edge. Nothing magic about it.
Sorry, I meant "surface" not "edge" but you get the idea. As long as I'm here - the type of metal makes a big difference in rigidity -- I assume this "C Channel" is regular old mild steel.
I have a White Oak dining table 5' X 5, it was edge jointed using #20 buscuits 8 yrs ago with no noticable movement. I've seen a bunch of these tubers using C-channal with no need to. I think its a tuber fad are they'er not the wood worker they think they are.
Truth or full of shit, this video was a 10/10 regardless 😂
I have done this. It was on a panel for the end of a dishwasher. I just don’t trust 9/16 plywood.
Tell us all those stories in the comments. I'd love to not read them. 😆 Thank you for that. 😆
Who was that dude without the glasses? Did you hire a new helper?
I do add c-channel in large single slab pieces, or anything with epoxy. And that's because epoxy sucks. Yes I make them, but its a trashy product and i've been slowly getting away from it altogether. I do not trust any epoxy table, regardless of cure time, to hold its original shape. There is too much flex and uncertainity on how it will react with moisture, temperature and light/sunlight variations over the years. $50 insurance and an hour of my time, is most definitely worth it on commissioned pieces.
Otherwise, I totally agree with everything you have touched on. One thing I would also like to add; is that not all c-channel/steel is made the same. The piece you have in your hands in the beginning is a very slight c channel. The example you showed from reddit was a slight stronger channel but again a relatively weak piece of steel (not saying it mattered in that particular case), I typically get my 2" c channel from a local steel shop and it is very heavy. I think wood forces, in the right condition, could bend it, but it is reduced even more.
just my 2 cents. Cheers
Yep
Who was the young guy with black hair doing the glue up?😅
I thought you were ABSOLUTELY going to say your backside was eatin' height
I don't know if that means I have a dirty mind or you have a dirty mind that has infected my once-clean mind
I am going to have to get therapy after watching Shannon’s face on your video
Idea: You could have held up a “file” or rasp when you said “defile”.
1:51 Never wear gloves when you are working with table/miter saws, a drill press, or other fast, and strong, rotating machines!! If a glove gets caught, it will pull your hand in the blade/drill etc...
C channel¿???!!?? What the???
I have numerous tables I have made in my house and no one has ever sat down with a straight edge and assessed the top before sitting down for a meal. I don't even have to search my guests for laser levels or steel rules before entry. Never has any body complained. Remember there are only two perfect things in nature
Matt Cremona and puppies?
Well crap, just pay attention to the picture, the c-Chanel doesn’t have a slot for movement 🤦🏽♂️🤦🏽♂️🤦🏽♂️🤦🏽♂️
Duggee!
It's cheap insurance
Legend has it that God put c-channel under the four corners of the earth to keep it flat, and we can see how that turned out.
Lol...ummm A.I. Shannon?
Actually I'm convinced that Shannon is completely AI generated and not a real person.
@@woodwhisperer Could almost rival Max Headroom. Some one should work on that😁
I DON'T USE METAL IN MY PROJECTS EITHER.
Please don’t do the weird talking head thing again :)
LOL, I hope you love to not read this.
Thanks for the video.
Damn it! I read it anyway!
I think you said it yourself it’s insurance. It may not be needed in a lot of cases but we also don’t need health insurance the majority of days of our life. Insurance is there for the rare times you do. The cost of using c channel is small compared to the cost of fixing a table that warps or cups. If you are making a slab table or a hardwood table the wood alone costs hundreds or thousands of dollars. The c channel and fasteners is nothing cost or time wise.
I think the better analogy here is more like an extended warranty. Will you need it? Only if the manufacturer messed something up or you have horrible luck. Which is why I usually pass on extended warranties. :)
I can see what you are saying Marc but I also think saying it’s a waste of time is also incorrect. I’ve built two tables and a desk and haven’t used c channel and I’m fine with that risk but I only build stuff for myself it my desk or kitchen tables cups 1/8 or even 1/4 of an inch it’s fine it’s still functional. For someone who makes a living making expensive custom furniture an unhappy customer with a non flat table is a much bigger issue. If I was getting paid based on my quality I would use c channel as an insurance policy every time.
But... breadboards are ugly
Then don't use them. :)
@@woodwhispererokaaaay
Please don't use the animated head in the corner in future videos, its REALLY annoying and trying to avoid looking at it while seeing the real content gives me a headache. Like having someone keep flashing a really bright light in your eyes while trying to watch a movie at the theatre.
Love to not read them? Really?
0:13 I had no idea how big that C channel was until I saw the banana, thanks for including banana for scale 😉
I'm still stumped. I'm gonna need to see it in football field equivalents... or elephants.
The problem isn't solved; the variability of the size of the banana makes your otherwise astute observation moot, and still unfactored in a factual way. Damn it, Marc @woodwhisperer. You've confused the entire universe with your shifty banana.
Thanks for this. C-channel makes sense if you're doing a slab table & just attaching hairpin metal legs to it.
With more traditional wood bases, I always saw the base as part of that stabilizing structure keeping things flat.
My c channel story:
Im working on a 12 ft white oak conference table (its a monster) It was flat after the glue up for a day or two but developed a 1/4+" cup in the center. I installed 4 sticks of c channel underneath and was able to get the cup down to around 1/8" (with hopes that the base adds even more stability.
I could be doing something wrong but i see cupping happening often in my larger dining table builds
“Leave comments for the algorithm that I’d love to not read”.
In present to you the most honest woodworking content creator in your YT. 😂
Did you leave slots in the wooden batons if your tables without c Chanel, or did those just behave well enough without that?
Shannon has never looked better...
C channel and its use in wood has always amazed or should I say amused me! The first amazing or wait amusing thing is folks have flat stock formed into what they are calling "C Channel" which as a structural member goes it's a major NO NO! and even when your using actual C channel it is engineered to be used on edge and not flat like folks use it. the last amazing or amusing part is that the channel is attached to the slab in multiple locations with threaded inserts! Oh wait isn't the threaded inserts the weakest point? and then assuming the channel is providing support when the only strength are the short vertical portions of the channel. Ok enough! I will leave you with this thought! I believe it's been said that the interweb is a huge echo chamber! Good day
Thanks a bunch for all the tips, Marc! 😊
Yeah, I'm planning on an outdoor table and I'm considering C channels...
Anyway, stay safe there with your family! 🖖😊
Well you got me to click and watch the video. Well done. Well done. :)
Ahhh, Cane's. I've had a lot of Canes in my time.
Hey! I saw Superman! lol
IMO, 20 years out all these river tables are going to be piles of junk with cracks all over 'em.
I can only hope.
I've never understood those things. I mean, it you are going to all that trouble, why not go all-in on the outdated kitsch and embed a few compact discs or flip-phones?
😝
You don’t have to read this, but ever like is engagement.
0:48 Disappointed you didn’t make Shannon Canadian
I 100% agree. About 1 yr ago I built a farm house style table from kilm dried ash. 13.5 ft x 6 ft x 1.75 inch thick.
I almost added channels iron, but Marc said in one of his earlier videos that channels are not needed to glue together, kilm dried lumber. He was right. Table is very flat.
Thanks for the great advice Marc!!!!
This video was really helpful bc I was just pondering about whether C channels are helpful for large table tops made with dimensional lumber. Thanks for sharing your opinion!!
Slabs move more than boards, but it's still not even necessary. This is what happens when "woodworkers" who pour plastic on slabs start handing out free advice.
Does this C-channel idea actually work? Doesn't seem to me like it should - I mean if you took that C-channel and spanned a 3' gap, I bet it'd take less than 50# of force in the middle to deflect it 1/8". Not much more to get 1/4". If you have a 3x3 piece of wood that's 1 1/4" thick, you'll need a lot more force than that to get it to deflect 1/8". Maybe enough to break it since you're going across the grain.
LOL, banana for scale... nice.
Interesting perspective.
"I'd love to not read them" bwahahaha... I love it. What a way to end it. That comment alone made me hit the subscribe button.