A misunderstanding of the end-grain glue "myth" video?
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- čas přidán 24. 07. 2024
- Mr. Sullivan's video and tests were great, but some folks are missing the point. Let me explain what I mean...
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The two videos I spoke of:
Mr. Sullivan's "Glue Myth" video: • Glue Myths: 1. End grain
Marc's response: • End Grain Glue Myths |...
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*The two videos I spoke of:*
Mr. Sullivan's "Glue Myth" video: czcams.com/video/m7HxBa9WVis/video.html
Marc's response: czcams.com/video/Fuvq0FDsUC0/video.html
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-Instagram: instagram.com/stumpynubs/
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Fantastic explanation. It definitely helped to understand better how wood and glue works together.
If you rub the glue with your thumb as if you were trying to fill those pores at the end grain in both directions and on both ends, and wait for the glue to get tacky and add a little bit more fresh glue and put your join together and Clamp it, you will get a very successful difficult to break glue joint
Dear Lord it's sad that a video like this is necessary. But because it is, thank you for going to the effort of explaining. Sullivan: "I'm tired of the myth that glue on end grain adds zero strength to the joint. Let's find the real-world numbers." Audience: "Oh wow end grain glue is strongest! No need for joinery, duuurp!"
The point of his video was to prove that side to end, or side to side, glueing will produce a weaker structure than end grain to end grain, it’s irrelevant what fails first the glue or the lignin, the end product is weaker than grain to grain connection. Your are confusing people even further.
@@soundtrancecloud5101 so are you only going to make furniture out of end-to-end pieces of wood? I’m curious how that will work. The reality is that Mr Sullivan didn’t make any claims (beyond a slightly click-bait-y claim of refuting myths). The problem is the large community of people who took what he showed and immediately started applying it to situations that it doesn’t apply to. It wasn’t a refutation of joinery, but that’s what too many people decided it was. They heard what they wanted to hear, not what Mr Sullivan actually said. Nice to know it’s not just politics.
James: Thanks for what I feel is a fair commentary on my video about end-grain glue. If viewers came away from the Glue Myths video with the idea that I am promoting end-grain joints, or that they should start making furniture out of 3" square blocks, then I failed to convey my thoughts clearly enough. I am trying to put together some objective, factual information about how glue works. My hope is that this information will be used as a tool by savvy woodworkers to design joinery that is strong enough to perform its intended purpose.
Idk why so many people are misunderstanding your video sir.
I mean it seemed clear as day to me, that you were just showing that the glue bond isn't weak on end grain to end grain glue ups, and that side grain glue ups will fail before glue because the lignin is weaker than the glue bond.
Looking forward to more videos on the subject
I believe that any strength test should consider the type of load. The tests I saw were all in bending. But to be more comprehensive I suggest shear force, bending moment and torsion tests. Compression isn’t applicable for a glued surface of course. Additional factors could include glued surface shape for example I-beam shape.
Patrick's video has sparked a lot of conversation in the woodworking world but what has amazed me is how civilized and productive every comment, analysis or response has been. It's a credit to just how awesome our community is!
@@robertjones9518 Mr. Sullivan obviously put an enormous amount of effort into his testing. It doesn't seem reasonable to suggest that he manufacture all of testing devices needed to perform all the tests you've identified.
My constructive criticism of Mr Sullivan's work is that it doesn't appear to change anything we know about joinery.
Thanks for keeping this a conversation between craftsman and not a mud flinging contest. I appreciate you, Mr. Hamilton.
@@charlescox290 One and the same. You might leave, but you’ll be back.
This is the epitome of academic critique. Each researcher adds to the body of knowledge which is shared and comented upon by others. Everyone benefits from the peer review. Great job to all!
It's almost like a peer-reviewed paper, only it's reviewed after publication.
@@timothyball3144 :,)) Yes collab. WOOoOoOo
If scientific peer review was as good as the peer review going on here then science would be on to something. So much of scientific peer review is pal review. Good job, guys!
To be fair, stubby nubs didn't do any research.
@@shrimuyopa8117 Except for working with wood and glues for years.
James, you should be ashamed. You make perfect sense, clearing up misunderstandings and confusion, which is completely out of place in a video and, I believe, a violation of CZcams policies. Based on what I've seen in a number of others' video, you are supposed to leave people MORE confused.
:-)
LOL
Now your'e thinking internet LMAO
I like that it got everyone talking. In my office, two engineers at a cubicle will start the discussion on how to fix a problem, (or build something) and a half hour later you will have 4-6 people going over the problem/job, all learning and looking for the best way to git er dun.
4-6 engineers all arguing about the price of tea in China, meanwhile the one blue collar guy with grease on his fingers "gits it dun"
@@strangevisions5162 That's good if you're building a table. It's not so good if you're building a bridge that will see rush hour traffic for decades or an airplane that's going to carry many tons of people and cargo. Horses for courses.
You could experience the difference yourself by doing something as easily accessible as building a custom UAV (drone). You can certainly slap a bunch of parts together and see how well it flies, but at some point you might find that it's worth reading up a bit on the dynamics of rotor-based drone flight, available parts and tech, and the experiences of others, then taking that information, doing a little design work (i.e. engineering), and building based on that work. Test, refine, repeat. Now imagine if you had to design one to perform a specific goal, carry a specific payload, weigh less than a predefined limit, and pack down to fit into a backpack. And if you're lucky, your drone failing in the field won't result in getting anyone killed, so you won't have that hanging over your head the whole time you're designing it.
But sure, engineers are all just goofing off while some grease monkey -- who won't face _any_ consequences if the design fails -- is really doing all the work.
That's an easy trap to fall into: everyone has their own job to do, but no one will butt out and let the others get on with it because everyone wants to show how important and clever they are. In my office, it's policy that you don't butt in to others' problems, as everyone's paid to do their own job, not someone else's. Works well.
The takeaway from his video, for me at least, was that when making small simple projects I no longer have to bend and contort my designs to avoid the dreaded end grain butt joint. It's really simple, you just need to understand it's limits and it's obvious that it's limits aren't quite as limited as previously thought. Not sure why it's such a big deal, honestly. As I said on another video, if someone watched Patrick's video and came away with "sweet, now I can throw away my joinery equipment and just use end grain glue joints" then those are not people you want making furniture anyways.
Joints are also subject to wood movement, something not factored into the original test. Since glue can't withstand wood movement over time your butt joints will fail long before an interlocking joint.
If you're making anything that's not considered immediately disposable, you should still avoid butt joints even in small projects.
Yes weaker joints will be better for movement...makes total sense good sir.
@@andreyandrey2645 yes, in fact. A weak, flexible joint would be preferable to a strong, brittle joint in many cases. Although, I actually have no idea if I matters here or not. You see it come up in metallurgy a lot. Where you must balance hardness and durability against each other
@@andreyandrey2645 wood expands and contracts cross grain. End grain joints are cross grain. Long grain joints do not see the movement end grain joints do.
@@eeguy77 both directions see movement; however, the cross grain direction sees more as it is subject to both humidity and temperature while grain length is effectively subject only to temperature. (i.e. essentially grain length is affected by one variable while grain width is affected by two). As such we see greater changes in width and thickness, than in length. That said, wood still moves in all directions -- basic physics.
As for glue's ability to deal with wood movement, you are correct when referring to certain glues, nut not all glues. Older crystalline glues (e.g. hide, fish, acetate,etc.) do not handle movement well over time. They do hold well initially but they continuous cure until they full crystalized. At that point, virtually all movement of the joint (e.g. temperature, humidity, mechanical stress, etc.) acts to break the crystal lattice. Fortunately, many of these joints can be re-liquefied by simple heating. resulting in restored resistance to movement (a more than 150 year old Joiner's repair technique).
Many modern glues maintain a degree of plasticity unless acted upon by extreme temperatures (over 100 degrees F), or other harsh chemical conditions. PVA glue is an excellent example. Its main initial advantage, besides price, was its over 100 years of plasticity. Typically wood movement has no meaningful effect on properly glued PVA joints. Properly glued meaning that all surfaces of adhesion were thoroughly coated before assembly and allowed to cure completely before initial use. Complete curing is typically under 12 hrs.
That said, other modern glues are crystalline in nature. Cyanoacrylate (CA) is an excellent example. It holds well initially because of the tensile strength of its crystal lattice. However, over time the glue cures to a pure crystalline form which while strong in terms of hardness, is also brittle, and so does not withstand joint movement over time as well as say PVA.
Glues are chemistry. The reason there are so many is because they all work differently. So in order to speak meaningfully about them, one must first limit the topic to a specific formulation category. Formulation means their chemical properties, and not upon what they are applied (i.e. PVA, Hide, and Fish are all sold as "Wood Glue" but each is a very different formulation).
So instead of grossly over simplifying several topics and being dismissive of others, please present you ideas in proper context and with a degree of courtesy and decorum. Polite discussion is always welcome, but rudeness and divisiveness almost never are.
I really love that Mr. Sullivan’s video brought up some interesting and hard to refute challenges to some age old assumptions about glue joints. I’m also really REALLY grateful that it’s spawned a number of response videos from great educators who now get to expand on how joinery gains strength and how to make things as strong as possible. Seems like this will only make everyone’s finished products better with a deeper understanding of what’s going on.
@@socratis236 appearantly there was a myth that when using wood glue only, end joins are weaker than side joins, which has now been disproven
@@socratis236 I suggest you watch the original video. It’s linked in the pinned comment
@@Keneo1 I am asking you directly, since you have an opinion. I am interested in it.
@@woodscholar6705 I’m sorry if I gave you the impression that I had an opinion. I was merely stating what I had observed
@@Keneo1 But you stated that the myth had been disproven so you have given an opinion by making a judgment! I think lots of us would be interested to know how. I think the questions asked by Socratis are quite straight forward in exactly what has been disproven. You said 'when using wood glue only, end joins are weaker than side joins, which has now been disproven'. How does a glue only join stand up in a chair leg!
From what I saw Mr. Sullivan's video did cover all this, but not explicitly.
Think this video is a great add-on, and helps to bring that lab test view back to the workshop.
Very nicely done.
So delightfully refreshing to see a respectful and appropriate commentary from one CZcamsr to another. Truly enjoy your presentations!
Your academic approach to the subject testifies to the depth of your knowledge of woodworking from many angles, as we who watch your videos can attest to.
One of the best videos I've seen in a long time. So well executed and easy to understand.
Thank you, I have had this same arguement twice today with friends. It shows that people really only take what they want from videos/articles etc. I have always held to the idea that adding a little more glue to anywhere there is endgrain and encouraging that soakage helps to reinforce the joint, my imagining always was that this was like adding hundreds of little dowels. I'm glad both you and Mark pointed out the leverage differential between real world and the Sulivan test. It had all been an interesting opening of an age old can of worms
The skepticism me says he knew what he was doing and the CZcams viewers didn’t disappoint!
It’s a whole new can of worms for the tons of new woodworkers around now that learned everything online.
I sometimes make small frames where mechanical fasteners are impractical. I've found that Wood Hardener (Earls) soaks into the end grain very well due to its low viscosity and provides a good base for the glue.
@@GarrisonFall you can also try splines to add more glue surface areas and grain fiber into the joint.
Thank you for adding some much needed perspective to this issue.
Wood movement is also something to bear in mind when gluing end grain to long grain. The long grain bit won't move along it's length, whereas the end grain will change dimensions along its width. One grows while the other stays the same and it might compromise your joint overtime.
So maybe a more precise way to say what the original video proved is: “All glued wood joints have similar strength at the joint, but wood will split near the joint when a side-grain joint is stressed beyond the strength of the wood’s lignin, and end-grain joints will split at the glue joint at about twice that level of stress. Because lignin alone is weaker than glue, and glue is weaker than the lignin-cellulose fiber matrix.”
At the glued interface would be a better definition. Otherwise you would need to define exactly what constitutes the joint. Like in a mitre joint is it just the interface or is it the square (or rectangular or whatever shape you end up making) formed by tracing the inner corner to the outside edge of each work piece? What about a dovetail joint?
Also technically you couldn't say that all glued wood joints have the same strength at the interface bc it's entirely possible that for example long grain on long grain glued interface is stronger than than the glued end grain on end grain interface.
But beyond that your conclusion stands
Absolutely flawed conclusion. The greatest moment would be in the center. If the glue were weaker than the long grain, the glue would have failed first. But because lignin is weaker than the glue, the section of the lignin closest to the center failed first on long grain to long grain joint.
Because end grain is stronger than glue, glue failed first on end grain to end grain joint.
Any time a person explains a fact in a manner that allows others to understand it more clearly, something truly useful has been achieved.
I really enjoy your video's such as this one. It feels like I just had another lecture of 'woodwork university'. Always elaborate and in depth information that help me better understand woodworking. Keep up the good work!
I love how you explain things so clear and concise
I love that you’re teaching folks about the science and engineering principles of our craft! Very well done Mr.Hamilton!
Easier than taking Statics and Solid Mechanics over again.
I definitely concur about respectful addressing, Mr Nubs.
YOUR OPINION DOES matter in my humble opinion James!! I always look forward to learning from you and have learned so much! Thank you James for this GREAT explanation!
I had to glue in a new board on the boom on my boat after pulling the old section off. I was told to never use end grain joints but instead create a 12:1 taper so you get a long glue area. So instead of having 4 square inches of surface area, I had 48 square inches. I think you said it well when pointing out that the real test should be end grain joint vs a virgin board with no glue joint. That is, after all, the goal of my boom repair. Make it as strong as if there were no joint.
I think the most interesting conclusion is that glue *bonds* are effective on end grain, enough so to not be the failure point. Outside of everything else, this is directly against what I've read and been told, and is good to know.
The problem is end grain to end grain is nearly always going to be high leverage joints by nature of the fact that wood is significantly longer than it is wide. This is why you need more strength than a simple glue joint cab give you. You need mortises, half laps, splines, etc.
That’s not true. They are surprisingly effective for a VERY short term. Take that same end to end test and wait even just a month and it will have weakened enough to go snap the joint with your bare hands.
@@davidpeters8813 You are missing the point or maybe just didn’t pay enough attention to the original claims. They have zero LONG TERM strength. They are about as useful as a suction cup. Sure it’ll hold up for a few days but that’ it’s they won’t maintain strength even through the full cure time.
@@korybricker4221, I await your scientific study with video showing initial strength of joints vs. time.
A factor that doesn't seem to be mentioned by anybody is the difference between the shear strength and tensile strength of the glue. In a tightly executed mortice and tenon joint, virtually all of the forces are shear forces, which the glue in combination with the wood fibers handles incredibly well. There's a reason why mortice and tenon joints tend to suffer from wood breakage at the base of the tenon instead of ripping the tenon out of the mortice. Sullivan's video tests only tensile strength, and thus only deals with one part of the picture.
In the case of the glue, and only the glue, there is no difference between sheer and tensile. These concepts only apply to a dimensional solid, not an amorphous liquid. The strength of a glue is typically measured by adhering two plates of the same material (who's known tensile strength is significantly great than the glue's adhesive and cohesive chemical bonds) to each other and then measuring the force required to separate them. Since the only thing that breaks is the chemical bond of the glue to itself, the net force is being applied to either a crystalline or plastic structure once the glue is cured. In either case, the total force is a function of the total surface area involved, while the net force is the amount required for a given unit of surface area.
For any "near zero thickness substance", it can be shown that tensile and shear strength are essentially equal. This is because both depend upon the substance's chemical bond strength and the portion of the substance to which the force is applied. In the case of glue, that portion is nearly 100% in all cases; therefore only the internal chemical bond strength is actually affected.
If you make a column of glue and then check tensile vs. shear of that particular column, then a difference will be shown because the surface along which the force must act change depending on whether it is co-linear, normal, or skewed with respect to the column. Since this geometry difference is effectively non-existent with general glue applications, it is very rarely, if ever, of meaningful significance. Instead we simply refer to the net bond strength per application (i.e. what two materials are being joined.) If the materials are different -- plastics to wood, wood to paper, polystyrene to glass, etc. -- then often only the lower of the two strengths is given as this will fail first.
Finally, after over 40 years of wood working, I have repaired just as many mortise & tenon joints where the glue failed as where the wood failed. Perhaps the most common case be in old chairs, especially Windsor styles. Over time, virtually all older glues (prior to the development of PVA) cured to a crystalline structure. This structure eventually fractures and the joint becomes loose. Depending upon the type of glue used, it is often possible to simply re-liquefy the old glue, add more if needed, and allow it to set again. This is especially true of hide, "old brown" (i.e liquid hide), and fish glues. Variations on these glues represented well over 80% of wood and household glues prior to World War I, and are still in major use today. Though today they are more commonly seen as specialty glues. Their uses include musical instruments, marquetry, veneering, restorations, flocking, and skin/material adhesion to name but a few.
that's exactly what i was thinking as i just watched this video. the miter joint with the spline in the middle, ends up being tensile strength of the spline, and shear of the glue. i do a bit of timber framing, and as i explain to people, keep all the joinery under compression loads wherever possible, no forces on the joint. same in glue, keep the loading of whatever you are building in the joint, and not what's fastening it together.
Not an apples to apples comparison. In a mortise and tenon joint, the strength of the joint is provided not by the glue but by the mechanical fastener of the tenon inside the mortise itself. The glue is pretty much there to keep it from working loose, not to provide the actual strength to the joint.
@@MichaelOlsen-Engineer "In the case of the glue, and only the glue, there is no difference between sheer and tensile."
Hmmm. Without testing, I think this is not accurate.
Tensile, is pulling two, (say end grained) pieces apart. This does rely on the structure of the cured glue, alone.
Sheer is applying pressure at right angles, trying to force each piece up/down force in relation to each other. Sheer has the benefit of friction as well as the structure of the Glue.
For example, if two end grained pieces that were not glued at all, were attempted to be forced up/down, there is significant resistance by the friction of the two surfaces, which increases with any pressure applied to force them together.
This principle is used to advantage in wooden boat building.
What are the shear and tensile strengths of glue?
There's a shortcut that undergrad engineering students use to get through timed tests: everything breaks in shear. Of course it's not literally true. But it's true often enough in practical work that it can be a good place to start guessing.
Also, this confusion of findings is symptom of reading/listening comprehension.
It's very sad that so many couldn't learn without making wrong conclusions about the findings.
I've watched all three video's and you are the only one that properly explained what we saw in the first video. Thank you!
As a structural engineer, I was fascinated and honestly surprised by Mr. Sullivan's video (because of the number of times I have heard respected woodworkers mention that end-grain glue joints don't add much strength). I was not surprised to the extent that I believed I had found the reclusive 'board stretcher' in the form of an end-grain butt joint to create longer boards but only to the extent that I wondered why so many woodworkers have believed for so long that end-grain glue joints are so weak. I have heard both Stumpy Nubs and The Wood Whisperer, among others, talk about not needing to put glue on the shoulders of a tenon or half-lap joints 'because that is end grain'. In truth, Mr. Sullivan's tests prove the fact that the shoulder is end grain would actually make that portion of the joint stronger (or at least not weaker because the lignin around the mortise is the most likely point of failure).
In looking at the confusion that has come about from an engineering perspective, there are two points that I believe are relevant here that I haven't heard mentioned in any of the videos offering further discussion or clarification of real-world ramifications of Mr. Sullivan's video. First is the orientation of forces on a glue joint. In all of Mr. Sullivan's videos, the force was applied as a flexural or bending stress across the joint, which causes high tension forces across the very top surface of the board and glue joint. In real-world scenarios, this tension stress across a glue joint primarily occurs in a butt joint where the glue surface is put in tension when a flexural force is applied. However, traditional joinery configurations shift that force into a 'shear' configuration where the stress at the glue joint is oriented parallel to the face of the glue joint and attempts to make one face of the joint slide, relative to the other. On a mortise and tenon joint, the cheeks of the tenon form a shear connection with the walls of the mortise when the pieces are either being 'racked' relative to one another or the tenon is trying to pull out of the mortise. I have not seen it tested, but I suspect that a glue joint in this shear configuration is far stronger than a glue joint subjected to flexural/tension forces with the same glue surface area because the actual wood fibers are engaged rather than being limited by the tensile strength of the lignin. Also, the glue joint is engaged across its full surface area where glue joints subjected to tension loads generally fail along the very edge of the joint that is subjected to the highest tension (the top surface of the boards in Mr. Sullivan's tests) and then the failure progresses rapidly downward through the entire joint so only a portion of the maximum strength of the glue or lignin is actually engaged at the moment of initial failure. Thus, shaping joinery so that the strength is derived from shear forces parallel to the glue joint rather than tension forces across the glue joint leads to a stronger overall joint.
The second issue is simply a matter of glue surface area. Regardless of whether the glue joint includes end grain, face grain or edge grain, the greater the surface area for the glue (and by default, the amount of wood fibers and lignin engaged), the stronger the joint will be. Most joinery methods that rely on glue are designed to maximize the surface area for glue. While it is possible to glue up a 36" wide tabletop solely with glue and have a piece that will last for generations, one would not dare do that same glue up on blocks that were only 3" long to create a 3"x36" piece, regardless of grain orientation. The glue surface simply isn't sufficient to withstand the forces, particularly when taking into account leverage as James mentioned. However, on the point of glue surface area, this is where I think Mr. Sullivan's video does offer some insight that might alter some approaches moving forward. As I mentioned above, I have heard lots of woodworkers decline to put glue on tenon shoulders or the end grain portions of finger joints simply because 'it is end grain'. But armed with the new information revealed by Mr. Sullivan's video, doing so is abandoning perfectly good glue surfaces that could add substantial strength to these joints.
I certainly won't be abandoning traditional joinery methods, but I don't think I will be quite as quick to discount an end grain surface as an opportunity to add strength to a joint configuration. Thanks to all who have offered something to this conversation. These discussions are a big part of how I learn and evolve as a craftsman. Cheers!
After years in media, one thing is consistent, people hear what they either want to hear or think they hear. All 3 of you made video's that were valuable in one way or another.
I look forward to the, don't clean off glue with water myth because it weakens the joint.
what do you mean "people only hear, what they want to hear"? The video clearly explains that we are ruled by lizard people.
@@ersetzbar. hahahahaha 🤣
There's no way that the water effects it enough to make a difference unless you're just freaking dousing it.
Your deference and respect in making this video is something our politicians should learn from. A respectful way to educate. Thanks for taking the time.
I’m just getting in to woodworking and a lot of these commentaries went over my head, but I am thrilled to be part of a community that values the pursuit of truth while conducting themselves like gentlemen.
Thank you for such a clear explanation of this. This is exactly how subjects should be discussed, in an open and honest way, not just criticising others.
I still reckon a lot of people are going to learn the hard way 😂😂
Best way to learn
Is that the long grain way or the end grain way?
The fact that Mr Sullivan's video requires "explanation" amazes me. It speaks about how smart (or dumb) we can be.
Under the same conditions, end grain to end grain glue is stronger than long grain to long grain. Period. Mr Sullivan's video does not explain joinery, different glues, techniques.. nothing more. It was pure and smart demostraron of a teacher how end to end grain glue is stronger. How you design your joints is a different story.
I think his emphasis on busting the "myth" that end grain joinery is useless, combined with the conclusion that "end grain rules" was what confused people. End grain glue joints are stronger than lignin, but when the leverage that occurs in real world furniture applications is considered they are still quite weak. He did touch on that a bit, but I think it was lost in the "hook" of the video. My video just seeks to clarify those points, not to contradict them.
Oswaldo - i agree!
Thank you so much! This video is a great 'companion piece' to Mr Sullivan's. I found it a bit hard to see the logical through-line across the different stages of his experiment - but you've broken down the variables very clearly. I understand it much better now.
Well spoken. I'm not a craftsman, and listening to you made me appreciate more those that are.
I think Mr Sullivan's video was 'gold' and really got at some key myths. The woodworking tips you discuss are how you compensate for the things he discussed e.g. add cross grain to an end grain joint or add a glued in biscuit or add a pocket screw or other techniques to strengthen any joint
Yes, that's where I ended up after watching Mr Sullivan's video also. But it was also helpful for me to hear that stated clearly in this video and in your comment. I'm a mechanical engineer, but I'm also a very amateur and inexperienced woodworker so my thinking is usually not complete on woodworking topics. The discussion really helps.
I remember learning about grain direction and wood strength when I was in "karate" as a kid. Turn the board one way and try to break it, it breaks you. Turn it the other way and "pop" breaks right in half, you're practically a ninja.
So you're saying I can use karate in place of my table saw?
@@FarmerJesse only for rip cuts on parallel grain, Jesse-san.
I got this when I watched Mr. Sullivan's video, got it again when I watched WW's video, and still get it now! Thanks for trying to help clear the air!
Thank you for this explanation on this issue and including several graphs and video portions of Mr Sullivan's test.
One of the best pieces you've ever written. Very well done.
Ditto.
I will expand on Mr. Warbington's comment to say this video was EXCELLENT. You have the clarity of a great teacher, and we all thank you for that.
I watched the original video, and I understood his conclusion. I'm a hobbyist woodworker and his video was still an eye-opener for me. I have long understood that gluing end grain was totally futile and would have zero strength
Very supportive video of Mr Sullivans methodical analysis of end grain glue jointing. Mr Sullivans video really explained in great detail to viewers the myths of end grain glueing. Good to see such a supportive video of the findings by Mr Sullivan, and a further explanation as to queries raised.
This was a great addition to Mr Sullivan's video. Thank you for sharing your knowledge.
As Yogi Berra said, "In theory there is no difference between theory and practice. In practice there is." Thank you (and Marc) for taking lab results and applying them to the real world of our shops.
Yogi Berra's quote only extends this error people have relating theory and practice. I assert a good theory is one that is good in practice. In Stumpy's video, his theory is the strength of a joint is a combination of glue, lignin, wood fiber and the physical relationship between all three. Where you put the force trying to break the joint makes a difference. If your theory lacks all four essential attributes of the joint, you will always have a separation between theory and practice.
@@BalugaWhale37 Yes, and that's exactly what Stumpy and Marc were pointing out. As a mechanical engineer, I always take the approach to reduce the problem to its simplest level and deal with that. In this case, it is: Long grain is stronger than glue; glue is stronger than lignin. With that knowledge, design your joint to meet the anticipated stresses of the finished product.
People only hear what they wanna hear. That's why I love that stumpy is taking this feud to the next level with a battle response video to MrSullivan
@@arglefargle123 learn to recognize sarcasm bruh
Great clarification. I really enjoy Mr Stumpy Nubs’ systematic and clear explanations on these videos. I started watching this particular one because I wanted to know what exactly the “turmoil” was, and then had to watch to the end just for the fun of it.
Thank you for this. I saw the Sullivan video, and thought to myself, there is more to it than this. I'm glad that you, and Mark S responded in a caring way to bring relavent context to it.
I don't understand the controversy, unless the title of the video magically broke the laws of physics. All he did was to measure and quantify glue strength relative to grain orientation.
The controversy is folks applying research results to draw completely wrong conclusions.
You can explain research to people but you can't comprehend it for them.
6:52, his boards are a LOOOOOOT longer end to end, so he had much more leverage (and thus his force was multiplied many times over) than the smaller test samples.
That's the point. That's what happens in actual furniture.
I don't get how these videos are disproving Sullivan's video. Sullivan mentions that most people think of gluing the long edges for edge grain and short ends for end grain, thus confusing their perception of the strength of the joint. Never does he say he believes gluing boards end to end is a good idea in practical use.
Sullivan already did an apples to apples test, but another test would be taking slices of a wide board across the grain and gluing them together vs. gluing two boards of the same dimensions but with the grain oriented the more traditional direction.
If nothing else, this may prove that gluing up those long awkward end grain scraps into larger boards may actually be viable for small to medium sized projects.
@@joshuathorson8813 - "Disproving Sullivan's video" is the opposite of what I said the goal of this video was.
Even more extreme, I can tear a sheet of paper with ease, but tearing it into two full sized thinner sheets is impossible.
@@joshuathorson8813 Tell me you didn't watch this video without telling me you didn't watch this video.
I love how respectful this community can be.
The three videos, Patrick Sullivan's, The Wood Whisperer's and yours should be mandatory viewing for any maker that uses glue to bond wood. The theoretical tests, the demonstration of how leverage factors into practical joints and your summary show comprehensively what the problems are and how to use the wood and glue to overcome them.
Many thanks to you all for creating these clips.
Some fellas like hot rods, dragstrips and the smell of nitro methane..
Others like bass boats, 6 pound smallmouths and drinking beer....
For me I like a good controversy about a wildly misunderstood and nearly irrelevant subject, as it applies to my craft :) :) Marc's and Patrick's video were both awesome and I appreciate your take on it Stumpy.
You all three had fantastic instruction and explanations
Be well :)
Recently subscribed to this channel and appreciate every video especially the lack of hipster woodworking BS.
I only recently viewed Mr. Sullivan's Glue Myth video, and was impressed.
Your video is a terrific clarification, with a great example using the spline in a miter joint.
Excellent conversation!!
I'm glad you did this video. Thank you for clearing a few things up
Hi James. Your opinion matters a lot to me and, I suspect, thousands of others which is one reason I respect you so much. You are knowledgeable, clear and precise. I too saw Mr Sullivan’s video and found it fascinating. So much detail and scientific expertise in a (relatively) easy to understand format. As I have said before, tonight I go to bed less stupid. Thanks for sharing 🌞
I'm not going to be as kind to Mr Sullivan as you because I'm one of those commenting that found myself in a
war of words with fellow wood workers. Mr Sullivan's choice of hyped click bait adjectives like "myth busting" by
a self proclaimed "Mythologist" was a sure bet to generate controversy. Mr. Sullivan's test fixture and test methods
were also structured to muddy the issues attendant to gluing end grain. They were definitely not designed clarify them! In the end Mr. Sullivan succeeded in the one and only purpose of his video .... to rack up "Click Count"! My proof is seen in the comments viewers left behind. Far too many viewers misconstrued the results of his tests!
Wakodahatchee Chris
Very well balanced and well presented. I think I have learned more in the last week about joinery and the properties of wood and the endless myths and discussions of end grain gluing…….than I have in the last 20 years. To drill down to this level of detail to the point where it all starts to make sense has made this very worthwhile for me.
James, you are just... Great ! I mean your video was perfect and it's very pleasant and instructive to listen to you and learn from you. You are by far my best and most appreciated woodworking instructor
I'm completely out of the loop here...
After watching this video, and using the links I provided to the original, you are now fully "in the loop." :)
@@StumpyNubs Hang on...is this an endless loop or one where we eventually vanish up our own rear ends?
@@daveturnbull7221: You can varnish Your rear, if you like, butt count me out.
Excellent explanation and summary !!
Enjoy your videos. This one was particularly well done !
I had the same takeaway after watching that video. The natural strength of long grain wood fibers are what joinery seeks to utilize.
The second I saw the original video I got excited to hear your take ! Can’t wait to watch
I liked your approach, the respect shown for fellow tubers and as always the concise and well presented story
Nicely done, with courtesy, professionalism and on-point explanations. Patrick Sullivan's response says it all.
Great analysis of his video. I had seen this and caught the same issues. I have not seen Mark’s video yet. Gonna go find it now. Great job on show them both respect while give a real World explanation and application
Well said. I appreciate your simple, common sense approach to woodworking.
Extremely well explained, and respectful to everyone’s videos. Bravo!👏
Perhaps the most thought provoking woodworking video I have ever seen. Thank you so much.
Really excellent and respectful addition to the understanding of joinery. This is how discussions are supposed to work.
Thanks for tip toeing through that subject! I make segmented bowls and vessels, so I’m familiar with the strength of end grain joints. Yet I had always assumed they were the weak joint in the project. I’ve always enjoyed your videos!
Like so many others, I will say this is an excellent video and your explanation was second to none. The respect you showed is a rare thing these days and for that alone you deserve the respect you have earned from a lot of people. Good job!
Way to go, James, and thank you! The key point about lignin-glue-wood fibers (in ascending order of strength) is what you cleared up that others missed.
Most people only hear what they want to hear, or only what they can understand, and don't bother to ask important questions like, "Do these results make sense?"
Next testing should be butt joint vs. long tapered scarf joint, both with the same glue surface area. Then take it a step further and test butt joint against finger-joint splice, with the same glue surface area.
Test shear strength in both directions, as well as tensile strength and torsion.
Mr. Sullivan made a great video. You basically made it better.
Thanks again!
I missed the original video as was busy in my workshop but your analysis makes complete sense and was well explained.
I loved Sullivan's video: It helped clarify the great strength of half laps and joint construction in general. You are trading excess long grain strength to compensate for lignum weakness.
Kudos to Patrick, Marc and you for using the scientific method to investigate and bring new understanding to an important part of woodworking. Keep asking good questions and seek better answers.
I'm really impressed with how the wood work community is taking these things in such civilized way. love Mr. Sullivan's video and yours too. such respect, to the point, adding more info and perspective to the topic rather than just fighting.
That's BC these are not "T" channels or "Commentary" channels, They're not in it to Bash one another and They engage brain before starting mouth
Thanks a lot for the info. Rarely I can watch somebody talking about glue and wood grain, and enjoy every second of it.
The lone sane voice among those crying that the sky is falling. Thank you for this video.
Sir, you have provided a plethora of useful information here. I have had to put on my thinking cap as a result.
I wish I had an idea as to what I am unaware. Thank you.
I love the emphasis to observe and scrutinize in context.
Bravo! Excellent clarification of the defining principles & standing up for the community without being dismissive or devisive. I also have to applaud Mr Sullivan who also did not overreact.
I'm impressed beyond description - I am astounded with your integrity!
You really are a valuable asset to the woodworking community!
Thank you Mr. Nubs! Great explanation.
Thank you Mr. Nubs. You are an excellent teacher!
As expected, this is a fantastic video. I am really happy to see Mr. Sullivan's video gain so much attention because it brings with it an opportunity to expand everyone's knowledge. I am an arborist and have wondered for a long time why more woodworkers don't show much interest in the biology of trees. More knowledge affords each person the opportunity to make a more informed decision, and these videos, beginning with Mr. Sullivan's, provide exactly that. Well done, Mr. Hamilton!!
I'm glad that your blog popped up for me to watch. I just recently watched Mr Sullivan's video and was kinda taken back but yours help me a lot! I really do like all your content! You are dead on and haven't failed at anything (yet 🙂) after watching your blogs... Hope ya have a really awesome day!
I love the respect you show Mr Sullivan. Hats off to you Mr Hamilton.
Very well put James & an excellent clarification of his video findings. Now I have to head over and watch Marc's video. 🤔🤔
"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world". -Archimedes
Wonderfully clear explanation. Thanks James.
I haven’t seen Mr. Sullivan’s video, but I think you explained and clarified this perfectly and respectfully. I love how well you explain the nature of wood. I believe you elegantly showed how short statements can often be misinterpreted. It’s important in almost anything that you must pay attention to all the information and facts. For example: If someone says they are burning down their house... that would be arson and illegal. If someone says they are burning down their house because it’s completely infested with bugs and deadly mold... that’s fixing a horrible problem. It’s the same action but the reason ir the “WHY” is completely different. Many people don’t take the time to find out the why! Thank you for explaining the why so well!
Well done, sir. Well done indeed! Excellent and informative discussion without getting pedantic. Thank you.
You nailed this explanation and I'm planning on pointing people here when the don't understand. I do wonder if there was a lab study done on long grain to end grain for glue effectiveness. The "shop test", if you will, would demonstrate that a long grain glue joint holds until the wood breaks and an end grain joint breaks at the glue line. But what we're observing is the breaking of lignin not the strength of the glue; which is why we all know that "glue is stronger than wood". Despite Mr. Sullivan's finding that wood fibers are several times stronger than glue.
You always have a great way of explaining things. You are an excellent teacher
Context is everything. Respect. Thank you
I feel that all the principles involving grain and glue are easily understood by anyone with a little experience of handling and working with wood but your analysis and explanation of this was, as usual, clear, fluent and beautifully constructed. I cannot imagine anyone failing to understand. Excellent!
my whole understanding of the video was that endgrain is stronger than we realized but obviously through the hundreds of years of woodworking, endgrain to endgrain joints arent used often for a reason.
Very good explanation and clarification. Thx.
Thank you, James. I had, indeed, seen that video. It certainly raised questions in my mind. I seldom rely on just the glue for these joints. I almost always add some type of mechanical fastener, pocket hole joinery, loose tenons, etc.