The pure wood concept is what we all should be aiming for! It not only looks beautiful but also saves materials and is structurally sound. Great joint work!
I'm not picking at Beau's choice of joint here; I haven't seen the entire grape arbor, and I'm pretty sure Beau has yards and yards more hands-on experience than do I. (I've really only framed clothesline poles and a few other odds-n-ends). But, I do have a bunch of timber framing books from modern masters of the art (Tedd Benson, Jack Sobon, WIll Beemer, B. Allen Mackie and more). Another way of making this connection would be to use a long through tenon, then wedge the tenon on the far side of the post, Dutch barn tie beam style. The disadvantage would be that the rail could not be removed from the posts as easily (if that matters, in this application). However, the through tenon could be tightened up later, if needed, and I suspect it would be sturdier, as well (though maybe overkill in this application - as I said, I haven't seen the full build). I do need to construct an adjustable raspberry trellis: T-post with double cross bars (top bar wider than the lower one), with notches in the cross bars to hold wires that run the length of the row. Set the wires in the wider notches for summer (fruit wood flopped and tied toward the sun, new canes to the other side as they grow tall enough). In the fall, prune out all of the past season's fruit wood, narrow up the wires to the close notches in the cross bars, and tie up the next season's fruit wood so the snow can't break down the canes. I may or may not actually "frame" the T-posts properly. They may just end up being channel posts, with 2x4 cross pieces, braced with a twist or two of more fence wire. Whatever the case, I like to see what other people have done, and how they did it.
The main barrier for using through tenons was that the posts were already in the ground. Little to no wiggle room. Through tenon and wedge would be a great choice for a structure that can be assembled on the ground and lifted into place. Good luck with your raspberries!
Whats the beef with using pegs?This leaves me questions of probabilities of failure/ weakness in the thin mortised dovetail. It will very likely work in this application but I am curious to see how this would perform with greater loads than a grape vine.
No beef with pegs at all. That is simply not what they are for. In timberframing, Pegs are not to be considered fasteners to hold things in place. Functionally, they are a tool to help draw things together, and aesthetically they have some appeal in certain applications, but if you rely on a peg for load-bearing structural integrity, that *will be* your failure point. The full movie shows a lengthy design discussion between Paul and me covering "to peg or not to peg," among other things.
@@beaumdavidson hey Beau, nice to hear from you. However, my very large, 4 story high barn of 120 years begs to differ with your statement that pegs aren't fasteners. The barn is in Maritime Canada, where some of the most ridiculous weather hits. 19" of snow in a single day? Lived through it without damage. Freezing rain storm "with ice ropes as thick as a mans wrist" - survived it well. 150mph wind from hurricane very nearby? Check. Still standing. I remember one day in 2016 where we had 120mm rain and +100km/h winds that had my barn moving visibly. Anyway, the barn is put together exclusively with pegs by amazing timberwrights over a century ago. Yes, I agree the pegs are aesthetically pleasing, but goodness me they work well as fasteners in the joints. Yes, they use typical mortise and tenon joints.Honestly, there are so many examples around like mine, that I question why you make a very bold (and foolish to me) statement that "in timberframing pegs aren't fasteners." Your *bolding* use is so silly that my barn and I had a good laugh.
Thanks for your response, Lito! Your barn sounds lovely. Are there any pictures you can share? I'm a sucker for that sort of thing. Now to your point. Cum hoc ergo propter hoc - the pegs are not *why* your barn is still standing. The pegs are a part of an integrated system that results in your barn still standing. The *roof* is the primary reason your barn is still standing. The roof mitigates damage from additional moisture entry points. My understanding is that pegs are never load-bearing - they accompany a shelf to transfer the load from beam to post. Relying solely on pegs results in failure. Our joinery is designed to eliminate the need for pegs. The angle of the tenon draws itself into the mortise far beyond the need for any pegs. There are some other advantages to this: you eliminate an early failure point for weather-exposed joinery (pegs) and eliminate additional perforations that would hasten moisture-induced rot in the primary members.
@@beaumdavidson Howdy again :) Yes, I do have pics to share, though I am reluctant to "put them out there". As for your joinery on this video at least, I can see that the dovetail is obviously designed to be fastener free - thats the whole point of the dovetails inception hundreds of years ago. However, my barn (and countless others) only have pegs as the "fasteners" and they have not failed through severe testing. My evidence dictates that your statement is simply false. In the mortise/tenons in the numerous joints I have here, the pegs are designed to keep the mortise and tenon in place, and thus retain the strength of the joint - particularly under the force of wind lifting the structure once the load is effected by the roof. One cannot stick a wind brace or knee brace into place (cross beam with an angled piece slapped onto the outside of the vertical/horizontal beams) with just a peg and have it work - it requires the mortise/tenon. I think that much is kindergarten common sense. My concern with your joint shown in this video is that a lot of the timber is now exposed to the elements which will hasten rot. I also feel that the dovetail housing is too shallow for general purpose building, though likely successful in this application with the light load. Thats why I am left with questions as to the strength. Wouldn't it be fun to test the joint in a variety of scenarios with some instrumentation for educational purposes?
Expirement! Yes! That's precisely what we're doing here. I am glad we are on the same page. :) Check back with me in ten years, and I'll update you on how it has weathered so far. I have a wild hunch that these joints will last 40 years, but we will monitor them closely each season to learn and ensure safety. For clarity, the viewer of this short clip may not realize the project's parameters. Let me give some of that in brief. The two posts were already installed in the ground to a depth of 8 feet. They spent the prior season as two of four anchor points suspending a series of giant shade sails to keep summer participants cool. Because the posts were already installed, we could not consider the classic through-tennon, as we could not spread the posts far enough to accommodate insertion. As you are surely aware, classic structures of the sort to which you refer are primarily assembled on the ground and then hoisted into place. Here, we had no such luxury. One of the failure possibilities you may be describing is that anywhere the members come into contact, movement may stress the wood fibers at those points, as depicted here in the design process thread: permies.com/t/219770/PTJ-Grape-Arbor#1867305. This also happens with through tenons, but I understand where you're coming from with dovetails. I think we kept the dovetails stout enough to withstand weathering for a long time, but to mitigate the stress of movement over time, I left a percentage of wiggle room at each of the pinch points, primarily above and below, but a bit to the sides as well. The animation shows a tight, but I asserted that this small gap would allow damage-free movement and provide a bit more drying capacity for seasonal precipitation. I will add that this project was done in very dry Montana, at a site where we spend much time and energy pursuing the most elegant, simple movements to go from tree to functional, appealing structure. I don't claim to have succeeded in this goal, but rather that we strove to find one pathway with this goal in mind. The same methods would only work for a short time in a humid environment. The last thing I'll add is that there are hundreds of ways to execute this project. This was our favored course of action, and I am simultaneously pleased with the outcome, looking forward to monitoring the resultant longevity, and eager to continue improving this and other future methods. I appreciate your feedback, as most folks familiar with traditional timberframing will have similar initial thoughts. It would be lovely if some expert folks in the field would take a moment to watch the entire movie and weigh in with the full context in mind.
AFTER ALL THAT, there is the matter of the nature of wood: Once wood is cut, it begins drying out. This causes it to shrink. That, in turn, causes it to split and crack. I worked closely with a friend who owned several cedar mills in the Pacific Northwet (Copalis, Pacific Beach). I am a wood worker, he was a shingle and shake maker. Because of my woodworking experiences, was was more than a little interested in preserving the wood I used on my projects. I asked him what he did to preserve the shingles and shakes, after they were installed. His stance was, cedar is rot resistant. I was shocked at my friend's response and tried to help him understand the properties that made cedar a good choice eroded over time, for the reasons stated. He didn't buy it, until years went by and his cedar shake roof was showing signs of taking hits from the Pacific Northwest weather. By then, it was too late for much of the roof, though a lot of it could yet be protected, and all the siding was worth treating. SIDE NOTE: When his mill got orders for cedar siding, the bundle price went way up. The only thing that changed at the mill, between top line roofing and top line siding was the labels. ANYWAY, what I pointed out to him was, in the summer, when the shakes were very dry, walking on them would crack and split them, but that didn't happen in the wet of other months. That was because the moisture made the shakes more flexible. It could go without saying you cannot keep the shakes moist all year long. That would be especially problematic, if you could, in the winter, when freezing would cause them to crack and split too. One of the best things you can do is, apply a non-hardening, deep penetrating protectant. Something like common oil, for example. Were you to oil a cedar fence, you would notice the application seemed to disappear within a month of warm, summer weather. A second application might seem to last just a little longer. Interestingly, a third application can show signs of having been applied years later. The reason the third application seemed to do more is, the oil is not evaporating. It is wicking deeper into the wood, leaving a thin amount nearer the surface. Adding more oil has a cumulative effect (building on previous applications that are still wicking to dryer parts of the wood. On a fence, it is not uncommon to note many of the cracks and splits seeming to disappear. This is because the wood is swelling back closer to its original state. I restored a 2" thick butcher block this way. I just kept adding oil wherever it soaked up over the course of a day. When the process slowed, I slathered on more [mineral] oil and just walked away. When I came back in a few weeks, many of the cracks and separations were no longer perceptible. The thicker the wood, the slower this process of replacing lost moisture will take. Another advantage of the oil applications is, wood full of oil will not take on water, which, again, freezes.
@@TurkyMacNam, okay smartass, want to guess what shingles and shakes are made of? Want to guess why you see huge splits and cracks in boards used for decks, logs on log homes and other structures made of wood and so on?
![Eminem - Like My Shit [Official Audio]](http://i.ytimg.com/vi/vx_IMvFkrfA/mqdefault.jpg)
The pure wood concept is what we all should be aiming for! It not only looks beautiful but also saves materials and is structurally sound. Great joint work!
Also wont ignite in a Carrington event
Not being an experienced wood worker, I also appreciate the detailed explanations of how to complete the dovetail. Impressive!
I appreciated that Beau explains his thought process on what he is doing and what he is looking for. I would love to see more joinery!
Me too!
I've seen dovetail joints before, but this one is exceptionally cool. The grape arbor should be fantastic!
So much to learn. Thank you.
Those poles are tall. Good job making them stand up solidly!
Beautiful wood work, great job you guys!
I'd love to see it when the grapes are on!
Paul said they have planted the grapes!
Great video! Thank you for explaining how these joints work. So clever! I would love to learn to do this!
Beautiful woodworking! Do you already have some grapes growing on it?
freshly planted
Crazy the hoops you have to jump through to install a cross-member on posts that are already in place.
Very clever design. So the drop in dovetail was used instead of a tenon because the posts were already in place?
That was the primary factor, yes.
I'm not picking at Beau's choice of joint here; I haven't seen the entire grape arbor, and I'm pretty sure Beau has yards and yards more hands-on experience than do I. (I've really only framed clothesline poles and a few other odds-n-ends). But, I do have a bunch of timber framing books from modern masters of the art (Tedd Benson, Jack Sobon, WIll Beemer, B. Allen Mackie and more).
Another way of making this connection would be to use a long through tenon, then wedge the tenon on the far side of the post, Dutch barn tie beam style. The disadvantage would be that the rail could not be removed from the posts as easily (if that matters, in this application). However, the through tenon could be tightened up later, if needed, and I suspect it would be sturdier, as well (though maybe overkill in this application - as I said, I haven't seen the full build).
I do need to construct an adjustable raspberry trellis: T-post with double cross bars (top bar wider than the lower one), with notches in the cross bars to hold wires that run the length of the row. Set the wires in the wider notches for summer (fruit wood flopped and tied toward the sun, new canes to the other side as they grow tall enough). In the fall, prune out all of the past season's fruit wood, narrow up the wires to the close notches in the cross bars, and tie up the next season's fruit wood so the snow can't break down the canes. I may or may not actually "frame" the T-posts properly. They may just end up being channel posts, with 2x4 cross pieces, braced with a twist or two of more fence wire.
Whatever the case, I like to see what other people have done, and how they did it.
The main barrier for using through tenons was that the posts were already in the ground. Little to no wiggle room. Through tenon and wedge would be a great choice for a structure that can be assembled on the ground and lifted into place.
Good luck with your raspberries!
Whats the beef with using pegs?This leaves me questions of probabilities of failure/ weakness in the thin mortised dovetail. It will very likely work in this application but I am curious to see how this would perform with greater loads than a grape vine.
No beef with pegs at all. That is simply not what they are for.
In timberframing, Pegs are not to be considered fasteners to hold things in place. Functionally, they are a tool to help draw things together, and aesthetically they have some appeal in certain applications, but if you rely on a peg for load-bearing structural integrity, that *will be* your failure point.
The full movie shows a lengthy design discussion between Paul and me covering "to peg or not to peg," among other things.
@@beaumdavidson hey Beau, nice to hear from you. However, my very large, 4 story high barn of 120 years begs to differ with your statement that pegs aren't fasteners. The barn is in Maritime Canada, where some of the most ridiculous weather hits. 19" of snow in a single day? Lived through it without damage. Freezing rain storm "with ice ropes as thick as a mans wrist" - survived it well. 150mph wind from hurricane very nearby? Check. Still standing. I remember one day in 2016 where we had 120mm rain and +100km/h winds that had my barn moving visibly. Anyway, the barn is put together exclusively with pegs by amazing timberwrights over a century ago. Yes, I agree the pegs are aesthetically pleasing, but goodness me they work well as fasteners in the joints. Yes, they use typical mortise and tenon joints.Honestly, there are so many examples around like mine, that I question why you make a very bold (and foolish to me) statement that "in timberframing pegs aren't fasteners." Your *bolding* use is so silly that my barn and I had a good laugh.
Thanks for your response, Lito! Your barn sounds lovely. Are there any pictures you can share? I'm a sucker for that sort of thing. Now to your point. Cum hoc ergo propter hoc - the pegs are not *why* your barn is still standing. The pegs are a part of an integrated system that results in your barn still standing. The *roof* is the primary reason your barn is still standing. The roof mitigates damage from additional moisture entry points. My understanding is that pegs are never load-bearing - they accompany a shelf to transfer the load from beam to post. Relying solely on pegs results in failure. Our joinery is designed to eliminate the need for pegs. The angle of the tenon draws itself into the mortise far beyond the need for any pegs. There are some other advantages to this: you eliminate an early failure point for weather-exposed joinery (pegs) and eliminate additional perforations that would hasten moisture-induced rot in the primary members.
@@beaumdavidson Howdy again :) Yes, I do have pics to share, though I am reluctant to "put them out there". As for your joinery on this video at least, I can see that the dovetail is obviously designed to be fastener free - thats the whole point of the dovetails inception hundreds of years ago. However, my barn (and countless others) only have pegs as the "fasteners" and they have not failed through severe testing. My evidence dictates that your statement is simply false. In the mortise/tenons in the numerous joints I have here, the pegs are designed to keep the mortise and tenon in place, and thus retain the strength of the joint - particularly under the force of wind lifting the structure once the load is effected by the roof. One cannot stick a wind brace or knee brace into place (cross beam with an angled piece slapped onto the outside of the vertical/horizontal beams) with just a peg and have it work - it requires the mortise/tenon. I think that much is kindergarten common sense. My concern with your joint shown in this video is that a lot of the timber is now exposed to the elements which will hasten rot. I also feel that the dovetail housing is too shallow for general purpose building, though likely successful in this application with the light load. Thats why I am left with questions as to the strength. Wouldn't it be fun to test the joint in a variety of scenarios with some instrumentation for educational purposes?
Expirement! Yes! That's precisely what we're doing here. I am glad we are on the same page. :) Check back with me in ten years, and I'll update you on how it has weathered so far. I have a wild hunch that these joints will last 40 years, but we will monitor them closely each season to learn and ensure safety. For clarity, the viewer of this short clip may not realize the project's parameters. Let me give some of that in brief. The two posts were already installed in the ground to a depth of 8 feet. They spent the prior season as two of four anchor points suspending a series of giant shade sails to keep summer participants cool. Because the posts were already installed, we could not consider the classic through-tennon, as we could not spread the posts far enough to accommodate insertion. As you are surely aware, classic structures of the sort to which you refer are primarily assembled on the ground and then hoisted into place. Here, we had no such luxury. One of the failure possibilities you may be describing is that anywhere the members come into contact, movement may stress the wood fibers at those points, as depicted here in the design process thread: permies.com/t/219770/PTJ-Grape-Arbor#1867305. This also happens with through tenons, but I understand where you're coming from with dovetails. I think we kept the dovetails stout enough to withstand weathering for a long time, but to mitigate the stress of movement over time, I left a percentage of wiggle room at each of the pinch points, primarily above and below, but a bit to the sides as well. The animation shows a tight, but I asserted that this small gap would allow damage-free movement and provide a bit more drying capacity for seasonal precipitation. I will add that this project was done in very dry Montana, at a site where we spend much time and energy pursuing the most elegant, simple movements to go from tree to functional, appealing structure. I don't claim to have succeeded in this goal, but rather that we strove to find one pathway with this goal in mind. The same methods would only work for a short time in a humid environment. The last thing I'll add is that there are hundreds of ways to execute this project. This was our favored course of action, and I am simultaneously pleased with the outcome, looking forward to monitoring the resultant longevity, and eager to continue improving this and other future methods. I appreciate your feedback, as most folks familiar with traditional timberframing will have similar initial thoughts. It would be lovely if some expert folks in the field would take a moment to watch the entire movie and weigh in with the full context in mind.
AFTER ALL THAT, there is the matter of the nature of wood:
Once wood is cut, it begins drying out. This causes it to shrink. That, in turn, causes it to split and crack.
I worked closely with a friend who owned several cedar mills in the Pacific Northwet (Copalis, Pacific Beach). I am a wood worker, he was a shingle and shake maker. Because of my woodworking experiences, was was more than a little interested in preserving the wood I used on my projects. I asked him what he did to preserve the shingles and shakes, after they were installed. His stance was, cedar is rot resistant.
I was shocked at my friend's response and tried to help him understand the properties that made cedar a good choice eroded over time, for the reasons stated. He didn't buy it, until years went by and his cedar shake roof was showing signs of taking hits from the Pacific Northwest weather. By then, it was too late for much of the roof, though a lot of it could yet be protected, and all the siding was worth treating.
SIDE NOTE: When his mill got orders for cedar siding, the bundle price went way up. The only thing that changed at the mill, between top line roofing and top line siding was the labels.
ANYWAY, what I pointed out to him was, in the summer, when the shakes were very dry, walking on them would crack and split them, but that didn't happen in the wet of other months. That was because the moisture made the shakes more flexible.
It could go without saying you cannot keep the shakes moist all year long. That would be especially problematic, if you could, in the winter, when freezing would cause them to crack and split too.
One of the best things you can do is, apply a non-hardening, deep penetrating protectant. Something like common oil, for example.
Were you to oil a cedar fence, you would notice the application seemed to disappear within a month of warm, summer weather. A second application might seem to last just a little longer. Interestingly, a third application can show signs of having been applied years later.
The reason the third application seemed to do more is, the oil is not evaporating. It is wicking deeper into the wood, leaving a thin amount nearer the surface. Adding more oil has a cumulative effect (building on previous applications that are still wicking to dryer parts of the wood.
On a fence, it is not uncommon to note many of the cracks and splits seeming to disappear. This is because the wood is swelling back closer to its original state.
I restored a 2" thick butcher block this way. I just kept adding oil wherever it soaked up over the course of a day. When the process slowed, I slathered on more [mineral] oil and just walked away. When I came back in a few weeks, many of the cracks and separations were no longer perceptible.
The thicker the wood, the slower this process of replacing lost moisture will take.
Another advantage of the oil applications is, wood full of oil will not take on water, which, again, freezes.
Wow, good thing they didn't build it out of shingles.
@@TurkyMacNam, okay smartass, want to guess what shingles and shakes are made of?
Want to guess why you see huge splits and cracks in boards used for decks, logs on log homes and other structures made of wood and so on?