Monday, October 4, 2010

Fan of the Fan (VII)

In this series I have looked at the geometrical challenges facing a carpenter wishing to employ fan rafters, ōgi-daruki, in a roof structure. We've seen in this series how it is difficult to reconcile the aesthetic considerations of obtaining both a nice pattern of rafter tips at the eave edge, and an even division of rafter spaces when viewing the rafters from underneath. We've seen 4 different Japanese solutions to this problem, the last of which, as detailed in the previous post, provides the cleanest answer to the lay out challenge, in my opinion at least.

Fan rafters as they are seen today tend to associate to, and derive from, temple architecture, and started becoming popular in Japan somewhat late in history, around the 14th~15th century.

There are two distinct patterns of fan raftering employed on temples - either the fan rafters radiate from a central point in the structure, or they proceed parallel to one another until they get near to the hip rafters, at which point they begin their fan.

The type that radiate from a central point, the same design as I used on the recent bell tower design, associate strongly to Zen Buddhism style architecture, or zenshū-yō (禅宗様). If you want to read up a bit more on that architecture and an example of a structure employing fan raftering of that type, I suggest you take a look at a post I did a while back, titled "Peace: Enjoy the Zen" where a six-sided pagoda with fan rafters is featured, Anraku-ji. Fan rafters originating geometrically at a central point are a natural choice for structures which are square or regular polygons in their plan.

The other type of fan raftering, in which the rafters along the eave remain parallel to one another until they approach the hip, is associated to "Big Buddha" style, dai-butsu-yō (大仏様), architecture. For an example, see my post from last year titled "Great East Temple"). This type of fan raftering is called sumi-ōgi-daruki (隅扇垂木), and is the more commonly seen variant as most buildings on the temple grounds are rectangular in plan, not square.

The earliest extant example in Japan of dai-butsu-yō is seen here at Jōdōji (浄土寺) in Nara, constructed in 1192:


Here's a classic example a two-tier eave with sumi-ōgi-daruki:


One more example of that style of raftering, for good luck:


While I stated that the use of fan rafters associates strongly to temple architecture, there are however residences that employ it, especially in the entry foyer, or genkan. Here's one such residence:


The portion of the building which projects out towards the viewer in the above photo contains the formal entry, and that is one area of the house which tends to receive more decorative attention (similarly to the guest room inside the house) than other parts of the structure. Here's a close up of that genkan eave:


Another residential example:


Nice copper gutters and rafter caps!

Even tea house (sukiya) architecture makes use of fan rafters occasionally:


So at this point, after all my droning on, the reader hopefully will have a pretty good idea as to the way the Japanese deal with fan rafters. Both the Zen style and Big Buddha style of temple architecture, however, derive from continental precedents, so now I'd like to turn to China and Korea to see how temples in those countries make use of fan rafters. I suspect there may be some people out there who would have trouble distinguishing Chinese, Korean, and Japanese temple architecture from one another, but believe me, they are as different as English, French and German traditional wooden architecture are from one another, and, similarly, share common points as well.

I'm not as into Chinese and Korean temple architecture as I am Japanese, so the depth of my analysis of those architectural styles and building methods here is necessarily limited. I do not read Chinese or Korean, so I cannot access source material from those cultures, and that is a major limiting factor on my understanding.

With those caveats in mind, let's have a look at a Chinese eave (and I thank R. Wiborg of San Francisco for allowing me access to his materials some 6 years back):


This eave, like virtually all of the examples of Chinese and Korean temples I looked at, is like the sumi-ōgi-daruki variant, in that the rafters do not begin to fan until they get close to the hip rafter. Notice that the composite hip rafter is marked out along its upper section with the positions of the 13 fan rafters.

Here's the plan view:


One observes a difference right away - in the above Chinese method at least, the fan rafters terminate directly onto the hip rafter. You won't see that in Japanese work. Note as well the steep climb of the curve, and how that climb is accomplished - by a scalloped filler board. This board forms then a wedge-shaped space in the eave.

Here's a Korean example showing the visual consequence of that tapered board:


Chinese/Korean fan raftering, which I will choose to lump together as they are very similar to my eyes at least, very commonly employ round rafters. Round rafters are much easier to deal with than rectilinear ones in fan raftering, as no extensive shaping is necessary to get them to conform to the other eave members. The gate house at the Ellison Residence employed pole fan rafters, so I have had some direct experience with that method.

In cases where a two-tier eave is used in China and Korea , a common system for dealing with deep eaves, the upper, or flying rafters will usually be of the rectilinear variety while the base rafters are round:


That was another Korean building - the choice of paint colors and patterns is one giveaway.

One of the things that strikes me about Chinese/Korean employment of fan rafters (not in all cases mind you) is that the rafters nearest the hip appear to be sunk half-way into the hip rafter. You won't see this in Japanese temple architecture, at least not so far as I have seen.

Another continental example, where the fan rafters at the hip are sliced length-wise and directly abutting the hip:


If you trace lines along the lower and upper tiers of that eave, you will see that the alignment of the rafters is not consistent with one another. Again, this is unlike Japanese work.

Another interesting difference relates to the employment of rectilinear section fan rafters in China and Korea: unlike the Japanese work, the sides of the rafter are not kept plumb. In many cases it would appear, the fan rafters are rotated along with the eave perimeter fascia:


Notice too the un-evenness of the fan rafter spacing on both sides of the lower hip. That would be considered a blunder by a Japanese carpenter. This rotation of the rafters is not attractive to my eye and conveys the sense, visually at least, that they could roll over from loading.

More examples of that fan rafter rotation, this one Chinese:


Another:


And another, this one with a curious staggered pattern of rafter spacing between the lower and upper tier:


I'm not, I will say, a fan of that fan. It looks disordered and choppy.

Returning now to the plan view of the fan rafters, Chinese-style:


Notice that the rafter tips for each fan rafter are cut square to the centerline of each rafter - the Japanese carpenters have improved upon this, I would say, by shaping each rafter end cut in a differential manner to achieve a smooth sweep of tips over to the hip.

Now, if the idea, as the previous illustration indicates, is to cram the rafters in one next to another, then the rafters cannot remain whole in section but must be tapered to fit in among their neighbors. The Chinese carpenters have an intriguing method for accomplishing that.

First off, they obtain their parallelogram rafter sections by slicing them out of a blank:


This looks economical, to be sure, however if there were any wood movement as a result of ripping the rafters out of the blank, you would not be able to obtain straight sections. perhaps they account for that, or perhaps they're not so fussy about it.

In the next illustration, for the round section rafters, a marking jig is constructed. This is a simple affair using a pair of notched boards to hold the rafter. On the end of these boards re marked a set of even spaces from a center point representing each rafter:


The bevel gauge is used, I believe, to set the rotation of the rafter relative to its position on the eave curve, given that the rafters rotate with the curve.

Back to those marks for the rafters - they are used with an ink line to snap the taper lines on the sides of the rafters, like so:


Here's the same procedure being employed on a round section rafters:


I am not optimistic that snapping a line from a single position across a round with a flat on it will result in a straight line, but I'll set that aside. The ink line is shifted to different positions for each respective rafter, and the result is the production of differentially tapered rafters which will fit against one another:


I presume the rafters are then fitted in place, adjusting as they go.

I'm not personally so interested in this aspect of Chinese and Korean wooden architecture, for it lacks, in my eyes at least, the sophistication and elegance I find characteristic of Japanese carpentry work. Some will be more drawn to the Chinese/Korean work because of their rusticity, color, and exuberance - of that I'm sure. Some will love the painted decoration. I tend to prefer the beauty of the natural material without augmentation or concealment, anything beyond hand planing and oiling is unnecessary, not to mention harder to maintain.

The extreme curves of the continental roof forms do not appeal to me, and I'm not much of a fan of those types of tile roofs for that matter with simple pipe-section-esque tiles. The Chinese roofs which sweep up to such an exaggerated manner at the eave remind me of photos of women from bygone days revealing their petticoats under their skirts or something like that, and while perhaps titillating or fun for the viewer at first glance, it becomes crass after you see it too many times. I can see however that if that vast majority of other structures in the built environment were drab, the Chinese temple architecture would be by contrast a relief.

The steep reverse pitches of those hip rafters seem to engender places where the roof tiles would be hard-pressed not to leak in certain spots, and any time where an aesthetic drive in architecture (curving that eave up more and more) subsumes considerations of practicality and durability I generally hop off the wagon. There are practical reasons for up-curving a hip, but beyond a certain point the structural argument becomes moot.

And finally, in terms of the fan rafters, their crowding together at the eave, which necessitates the tapering of the rafters, and the lack of attention paid to getting the spacing clean and well-aligned, well, I find to be a shortcoming in the Chinese and Korean buildings.

The Japanese, through working at solving these challenges for a few hundred years, have produced with their fan raftering an eave with the end cuts of the rafters in harmony with one another, cleanly aligned and spaced, and with a smoothly sweeping eave edge, regardless of where the eave curve begins (if there is a curve at all). That is, in my view, one of the unique triumphs of Japanese architecture over its continental antecedents.

Some people might put down the Japanese for 'copying' the work done on the continent, however in my view they have paid the highest compliment to the Chinese buildings of former times in their sincere emulation of the form, and later improvement of fan raftering. And, dear reader, this fan raftering but one narrow aspect of this ancient form of timber construction, and the Japanese have applied their process of continual improvement to all aspects of that form of construction. No stone, let me assure you, is left unturned.

So there is a lot more to see and learn yet in Japanese architecture - that's my conclusion for now. That's why I imitate the Japanese builders - their work is the best example going, in most cases, both in terms of technical sophistication and refined aesthetics. I know, without question, that the Japanese carpenters of the past had considered the details of everything they did in a most thorough manner, and it is only for me put the time in to discover what they did. While for furniture, I look to the Chinese Ming period masters, for architecture, it is the Japanese carpenters who I feel have truly mastered the art of building in wood.

12 comments:

  1. Hi Chris,
    I am a regular reader of your blog and really appreciate the effort you put into it. If I had the time, I would have taken one of your classes.

    I have a question concerning Asian architecture. Why the multiple cantilevers to support the rafters. For example the first picture in this post. It seems an extremely complicated system to support the beams the rafters are resting on. Is there a reason the supporting columns cannot be placed closer to the horizontal support beams thus negating the need for a system of cantilever to transfer the point load to the column?

    Peace,
    Harlan Barnhart

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  2. Hi Harlan,

    if I understand your question correctly, the simple reason that the support columns cannot be placed closer to the horizontal support beams is that the eave is quite deep. I mean, if the eave is to be 10' deep, then the wall column cannot be any closer than that unless you want that column to be in the way. The purpose of the deep eave is to protect the wall timbers from the sun and rain, so placing posts further out into the eave defeats that purpose somewhat, no?

    To carry an eave that far out from the wall, either the rafters have to be massive, and of tall section (which has its drawbacks), or there have to be intermediate supports, visible or otherwise.

    The picture at the top of this post is of a constructional system employed in the 12th century, and further it is a system that never won wide acceptance or became commonly used elsewhere in Japan. I'm not saying there is anything especially defective about it, only that it is unusual.

    That system IS similar to a modern day method called se-gai-zukuri, which also places an exposed support beam midway out into the eave, and employs the cantilever principal but not bracket complexes.

    Most of the beams in that picture are not what I would call 'cantilvered' exactly. The bracket complex functions to distribute the point load otherwise carried by the column over a number of peripheral points and thus maintain a flexible support system. It is very similar to a tree trunk being divided into a series of branches, each of which is carry a part of the 'load'. Distributing that load through a series of short arms and pillow blocks is a lot lighter than simply piling long timbers one upon the other to support a load out from a wall, and allows for reasonably even air circulation around the parts.

    True cantilevers in a Japanese roof, hanegi, are typically hidden inside the double roof structure. This allows them to be placed without concern for aesthetics and with rough logs instead of polished timbers. There is another type of cantilever, called a 'tail rafter', which is employed in bracket complexes, but it is not one of the parts in the bracket assembly seen in the first picture in the posting.

    I hope I provided a clear answer to your question.

    ~Chris

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  3. Hi Chris,

    We would like to correct some information pertaining to Chinese Architecture that are incorrect in your post(s). First, the notion that Chinese Architecture exhibit exaggerated curves at the corners of the roof is not "entirely true". China is a huge country and thus different regions will exhibit different "styles" of architecture. Let’s define two distinct categories: regional styles and mainstream styles. Regional styles refer to the Chinese Architecture built in localized and remote areas of China (such as the ones exhibiting exaggerated upturned eave corners). In contrary, the mainstream styles are the Chinese Architecture that is built in or near ancient Chinese Capital cities and do not exhibit exaggerated curvatures at the corner of the roof. Here are some examples of mainstream Chinese styles:

    1.) Qin/Han Style
    2.) Tang Style (inspired early Korean and Japanese Wayou architecture)
    3.) Song Style (inspired Zenshuyou Japanese architecture)
    4.) Ming/Qing Style

    Consider the following example: Zhengyangmen, the inner gate of Beijing's extensive wall and barbican system. The gatehouse survived up to today (Originally built in Ming Dynasty and rebuilt in Qing Dynasty).

    http://blog.udn.com/community/img/PSN_PHOTO/zhuzhu/f_4293105_1.jpg

    As we can see, there are no exaggerated eave corner curvatures.

    Secondly, genuine Chinese architecture exhibit clean and beautiful fan rafter layout and most importantly, they have plumb rafter edges. Two of the examples are presented below; the first illustrates tidy fan rafter layouts, the second image proves plumb rafter edges:

    http://www.struck.us/BikePics/China/2010-10-26%20102.JPG

    http://thumbs.dreamstime.com/z/hall-supreme-harmony-hall-eaves-beijing-33119561.jpg

    Lastly, we would like to present an example of a Chinese Wooden Architecture that we personally think is the paramount achievement of ancient Chinese carpenters: the Four Corner Towers of the Forbidden City.

    https://farm2.staticflickr.com/1493/24571943860_dec8cb5b1c_b.jpg

    And

    http://i.imgur.com/pSpdMkG.jpg

    They were built by the best Chinese carpenters in the Ming Dynasty. We are particularly awe struck by the fact that the carpenter(s) managed to get a tidy fan rafter layout despite the complexity of the roof type. Secondly, there is a legend that one of the four towers was actually dismantled. When it came time to reassemble that tower, the carpenters who were hired for this found it extremely difficult to put it back together and were all amazed by the talents exhibited by the original carpenter who did the design in the first place. With respect to this, I think that the Chinese carpenter has truly mastered the art of building in wood. These innovations have proved that they have left no stones unturned; that is the reason why Korean and Japanese carpenters have been inspired by their works. This quote offers a different perspective to your last paragraph of this blog post.

    Comments by Frank and Martin

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    Replies
    1. Before I respond to your post, who are you, "Frank" and Martin"? I appreciate that you shared examples of fine Ming architecture. You will note my caveat at the beginning of the discussion, "I am not as into Chinese and Korean temple architecture as I am Japanese, so the depth of my analysis of those architectural styles is necessarily limited. I am always open to learning more, however, I am curious as to your agenda. If you feel some need to 'defend' ancient Chinese architecture, that is understandable, but unnecessary. It speaks for itself.

      ~C

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    2. And re-reading your comment further, I might elaborate a little on that last paragraph of the post above. After looking at the photos you linked, I agree that there were some splendid examples of fan rafter work done on Chinese buildings. I think the spirit of my comment in that last paragraph, about following Japanese carpentry because of it's mastery, is more along the lines of following a tradition which is very much alive today. The most complex and refined work can still be executed in Japan, while in China these techniques seem, to my eyes at least, to have peaked 400 years back or further, and to have been largely lost in modern times. The same can perhaps be said for the furniture too. There were some amazing things made in the Ming Dynasty, no question about that.

      ~C

      Delete
  4. Chris,

    In response to your question of who we are. I am writing these posts with another person that is also interested in East Asian architecture and have opinions they want to share as well. Therefore, we formulated the above post together.

    It is precisely because you are not as into Chinese and Korean temple architecture and that your analysis of these architecture is limited, we feel we have the information to fill in the blanks for other potential readers of this post.

    About "our agenda," we feel like it is necessary to defend Chinese architecture. You mentioned that you are not an expert in Chinese architecture but yet made mentions of them and comparing them to Japanese architecture. I feel that it is unfair to compare an architecture that you even claim you are not familiar with to something that you know a lot of. If somebody who is not familiar with Japanese architecture but is familiar with Korean architecture starts comparing the two and using information which you know is false on the Japanese side, what would you do?

    On a side note, since you and I are interested in Asian architecture, it would be great to hear your opinions regarding the examples posted above.

    Martin

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    Replies
    1. Thanks for the reply. I presume your friend Frank is the one who often asks me about Japanese layout techniques?

      As you the pictures. Okay, the gatehouse in Beijing does have reduced hip uplift compared to most examples.

      As for (http://www.struck.us/BikePics/China/2010-10-26%20102.JPG), which you describe as a tidy fan rafter layout, I would tend to disagree. As mentioned in the post above with another example, the two tiers of fan rafters are not in alignment with one another. To my eye, the two tiers, while orderly considered alone, do not harmonize well with one another. All the rafter tips are cut squarely across, which is not the most subtle treatment.

      As for (http://thumbs.dreamstime.com/z/hall-supreme-harmony-hall-eaves-beijing-33119561.jpg), again, the tiers of fan rafters do not aline well to one another. The progression of curvature on the upper two-tier eave does not seem harmonious in shape with the one below. That said, the Hall of Supreme Harmony is a glorious building, undoubtedly a masterpiece. It was nice to see the rectilinear rafters keeping plumb sides, and I appreciate that you pointed that out.


      The Four Corner Tower pictures - I've seen that building before. I accept it is a highly crafted structure, however like all the other ones you showed, so highly decorated that I find it a bit numbing, gaudy even. That's a question of taste of course, so only an opinion.

      And for sure, if you find something on my blog that is factually incorrect, I definitely appreciate it if you bring it to my attention. I think that while you have found a few select examples which display plumb-sided fan rafters - what you term 'genuine' Chinese architecture, the vast number of other structures of which I have seen pictures of are far cruder. So, I would suggest that it would be more accurate to say that while examples of cleanly-done fan rafters were executed in ancient China, 99% of the rest, virtually all modern examples, fall far short of that.

      Also, in Japan, timber architecture remains a vibrant and developing art. Timber in China for large timber structures was becoming scarce by the 10th century, and hence most of the structures left today are primarily masonry buildings with timber roofs. I think the height of the art happened some time ago in China and, with all of the upheaval of the cultural revolution, etc., so much has been lost that is is difficult today to form an accurate picture of what went on before. I'd love to see Chinese technical manuals of roof carpentry which match the sophistication of what can be found in Japanese, however so far I have not seen that beyond what is shown in the post above. I'd be very interested to know if anyone in China today could execute those pinnacles of the craft which you gave as examples. As you mentioned, when the Four Corner Tower was reconstructed, the carpenters of that day found it very difficult to execute. You will not find such a parallel in Japan today. the top temple carpenters there can, by and large, build the same structures that represent the peak of that building art from the past. It's a living tradition, albeit one under threat from modernity.

      ~C

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  5. Hi Chris,

    First of all, thank you for taking your time to present your opinions. I really appreciate hearing opinions from others especially from someone as experienced as yourself.

    Yes you are right, Frank have been visiting your blog and posting discussions occasionally.

    I believe the reason why a lot of modern “examples” of Chinese architecture looks poorly done (such as the ones posted in your blog post above) is because they are not even Chinese architecture in the first place. They are often done by people without any carpentry or Chinese historical architecture backgrounds; not carpenters. Those people just build regular modern buildings and attach fake looking roofs with out of proportion rafters and brackets while marketing it as Chinese architecture for various purposes including tricking tourists.

    The tradition of carpentry therefore isn’t necessarily lost. As mentioned, the story about the carpenters not being able to build the four corner towers back is just a legend told to probably emphasize the difficulty in its construction. There have always been skilled carpenters throughout Chinese history to modern times. However, the shear amount of work done by the non carpenters (referring to the previous paragraph) overrides the work done by the true masters. Therefore, it gives off an impression that the technique is lost and that nobody can build buildings like in the past. In this sense, the Japanese have done a good job of ensuring that their cultural buildings are treated with respect and worked on by true carpenters. I presume that as China continues to modernize, they will pay more respect to their own cultural relics. Skilled carpenters may finally present more of their works and replace the in-properly built majority found today. An example that supports this hypothesis is the reconstruction of one of the Beijing gates (destroyed mid 1950s) back in 2005. This project was carried without the use of any nails relying only on joinery. This proves that in the modern times, the carpenters are able to replicate the work of Ming masters and that the tradition is still alive.

    In my opinion, one of the best examples of the tradition not being lost is the works being done by the Red Sandalwood Museum in Beijing. One of their recent projects was creating 1/10 scale models of all sixteen gates of Beijing. This project took 6 years employing hundreds of top craftsmen and carpenters. The 1/10 scale used for the models is also a carpentry tradition carried on from the past.

    http://mmbiz.qpic.cn/mmbiz/GL4KXAofZu4V2wiamSicLm6IL9y3T3JL9NMsYXvObPappD8e4aoB0VicHPsg9tHsxxSlhHjEGhYUXmWX39gxqllmA/0?wx_fmt=jpeg

    I believe this may be interesting to you because you run your very own carpentry workshop too. The woods used are Red Sandalwood for the frame of the building and Ebony for the fortress walls. More details of their work can be accessed through the link below:

    http://europe.chinadaily.com.cn/epaper/2014-11/21/content_18954111.htm

    As seen in the various pictures of this link, no nails are used and joineries are employed.

    About technical manuals, I have come across quite a handful of them some going quite in-depth. An example is the historical Yingzao Fashi written in the Song Dynasty. But as shown above, a lot of the knowledge was handed down by using scale models; master to disciple. I agree the Japanese have made impressive manuals.

    Your observation about there being more masonry building in China after a certain period of time is correct. However, there is an explanation to this and I will leave this to another post due to the character count restrictions.

    In summary, I would highly recommend further investigation into the Beijing Red Sandalwood Museum. A direct link to their main page:

    http://www.redsandalwood.com/en/

    It would be interesting to hear from a carpenter such as yourself of what you think about their work.

    Martin

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    Replies
    1. Martin,

      I appreciate the discussion.

      As for (http://europe.chinadaily.com.cn/epaper/2014-11/21/content_18954111.htm), if you look to the third picture down on that page you will notice a lot of clamps attached to the model, and indicator that the parts are being glued up. Hardly an aspect of traditional construction.

      The 'no nails' thing is a sort of buzzword which excites many who are not intimately familiar with timber carpentry. I take the idea of all-joined construction about as far as it could be taken in my own work, and I would not make the claim that large architectural constructions like temples are 'nail free'. It is misleading. If you eschew the use of metal fasteners altogether in construction, you can only do primitive structures, like farmhouse minka, in which the rafters and roof covering are lashed together with cordage.

      In timber construction involving rectilinear rafters, flat roofing boards and fascia, nails/spikes are employed to connect the parts. Even in very old construction, iron spikes were fabricated for certain junctions where all wood connections would provide inadequate strength. In places where there is a lot of seismic activity, many more metal fasteners are required. Where the structural timbers are lighter for aesthetic purposes, the use of metal, hidden as it may be, goes up. Joinery work and iron fasteners have gone together for about as long as humans have made metal tools. In modern times, the advent of cheap mass-produced nails, screws, and spikes has allowed for their proliferation of use. Formerly, such iron items were comparatively expensive to source/produce and thus were employed much more minimally.

      Looking at the model you linked made in 'red sandal wood', despite the money lavished on it I am not what you would call stunned by the quality of the work. It's okay, but not super clean.

      ~C

      Delete
  6. Chris,

    Thank you for your comments and opinions.

    About the Red Sandalwood project, I have seen and used those clamps before when I was taking a high school wood working course. We used those clamps when we were making a cutting board and it was used during the gluing stage. If the Red Sandalwood project really used glue, I think the reason behind it is because of security reasons. The models will be flown around to different exhibitions around the world. What counts is that they used joineries to build the models.

    About the notion of “no nails” construction, I do not see any places where they need to use nails in the framing of the “main structure” of a Chinese timber building (Not counting the rafters). I have a great example that I would really want you to look at. The link provided below is the last page of a series of pages that illustrates a step by step process of constructing a Ming/Qing Dynasty timber building. You can access the previous pages by scrolling down and pressing the link to the right of the words上一篇. This series spans a few pages starting from the bracket constructions to the end of constructing the “main structure” of the building. So you might need to go a few pages back if you want to start from the beginning.

    http://www.manda8.com/jwh1/144038269.html

    From the pictures in this series, I do not see a particular area that needs to use nails as most of it is heavily joinery based. However, I welcome your opinion if you think otherwise.

    Martin

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    Replies
    1. Hi Martin,

      It seems to me that it is wishful thinking that the reason that they used glue on that model was for 'security purposes'. The parts were glued, more obviously, because the parts in a scale model lack the weight of full scale parts. Two layers of sticks atop one another would not be held in the same compression as they would in a full scale building, so they glue them together.

      When I made mention of 'no nails' being a misleading idea, I was speaking more generally about timber architecture, regardless of what country it come from. The main parts of a timber frame can of course be put together only with joinery. Where there are frequent seismic events however, all-wood connections, particularly where the roof load is high (i.e., a tiled roof) are insufficient, and certain metal reinforcements, in the form of threaded rods and straps, are very often necessary.

      The link to the 'Ming' temple building: it was a bit humorous to me, though I know that was not intended. The person writing/illustrating that entry is obviously not an experienced timber builder, and at stages reveals he had certain details completely wrong and then revises his earlier drawings. I presume the writer is an architecture student - a person versed in CAD and not in real building work - an academic.

      When one looks at the details shown in the drawings, I was initially struck by the crudity of the connections. As I looked further, I realized that the connections were something the illustrator dreamed up. The use of simple dovetail splices between most timbers for example - -these are a rather weak connection, and if exposed to any tension, will yield and open up. Connecting two logs together at a crossing by way of a thin tenon and huge mitered abutments: a connection that is weak and will look very gappy when the timbers shrink. Then there are connections shown where a timber quarter-laps onto a log without any joinery being detailed - in any case, no matter what, the connection would be a weak one. Then there are the weird stub posts which are housed both ways for beam connections. Why would anybody do that? It would be easier and much stronger to splice the beams directly to one another and insert a floating stub tenon so that a post could be placed atop. Then there are places where a double-housed dovetail joint is shown - this is ludicrous. Housing a dovetail makes sense, but to double house it conveys no advantage whatsoever, and simply weakens the receiving member while adding unnecessary work.

      The goofiest piece though was where the upper hip rafters are attached. The first piece to be put in, the hip rafter forming the eave, has the dumbest connection I've ever seen done on the upper end. So much wood is cut away the joint would be seriously weak.

      Ming-era timber builders were far smarter than that I think.

      ~C

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  7. Hi Chris,

    Thank you for the detailed response. It seems that there are many things going on with regards to joinery. I appreciate you for pointing them out.

    Thank you for sharing your reason of why the Red Sandalwood project used glue. For me, I intended the “security reason” to mean that the pieces could become dislodged in flight when they ship it around the world to different exhibitions. Of course, this being the case because the model parts are lighter in weight than if they were life sized. With such risks, the parts may become lost hence the need for “security.” I realized after re-reading my original comment that it can come off with another message.

    As for the discussions, it appears that I may have been overly passionate. I am a fan of Chinese architecture so sometimes I find that when I discuss this topic with others, I can come across as overly persuasive or defensive. It is not my intention, more so my passion. As mentioned earlier, I am interested in East Asian architecture, so naturally I have touched up on Korean and Japanese architecture too and appreciate the sophistication of Japanese architecture that you presented throughout your blog.

    My original intention was just to point out facts such as “plumb rafter sides.” However it seems strange to come into someone’s blog just to correct them and disappear with only one post. So I decided to initiate some open ended discussions. As I do not have actual building experience, the links that I posted in my later replies were, more so, intended to learn from somebody who actually has hands on experience. These discussions were certainly enjoyable.

    Martin

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