It seems like the typical old log building around where I live in the western Piedmont of North Carolina is made from southern yellow pine logs hewed very roughly flat on the two sides facing in and out but not the two sides facing the logs above and below. This seems to include even buildings that were never lived in but were just for farm use. A few weeks ago I saw a couple interesting exceptions. One was a white oak log building that had presumably been chinked at one point, so similar to the standard log buildings around here in that respect -- the logs weren't tight together like I think of Scandinavian or northwestern US log buildings -- but the logs were round, not hewed on any sides. The other building was a hybrid of the two styles I've just described: the first 5 or 6' nearest the ground were unhewed white oak logs and then from there up the building was completed in pine logs hewed on just two sides. What's the point of hewing the two sides of the pine logs? Why go to the trouble? Was it just for the aesthetic? But obviously it wasn't just for the aesthetic on the hybrid building I described, because only the pine logs but not the oak logs were hewed.
Others more knowledgeable might know for sure but my feeling is they were making provision for covering up the logs later with furring strips and siding on the exterior and furring strips, lath and plaster on the inside. There are quite a few farmhouses here that have a log core hiding behind the walls. I look at it as a relatively quick, cheap horizontal framing system. Some folks got to the finished weatherboarded farmhouse, others hung their heads and lived in a lowly log house ... Times and styles have changed :).
I wonder if your hybrid had been repaired at some point and the lower logs replaced?
I saw Don was reading this and expected a very detailed explanation which involved complicated formulas, deflection charts, and 1800's gizmo's being used.
Guess my thought that the guy simply got tired after doing two sides and figured he would never get the place finished if he did all four is just about as good of an answer. :D
Time saved must have been a factor. They had to build the homestead and hunt or forage for food at the same time. The good ole days. :D
:D
I worked on one extensively enough that I imagined I was seeing 2 axemen. One was bigger and more skilled, large accurate cuts, the other was more pecking away at it.
Here's generations of remodels. First burnt lime and sand chinking. Then furring strips drywall and tile, this was the kitchen. White 5/8x6" poplar clapboards outside.
(https://forestryforum.com/gallery/albums/userpics/10017/markkitch.jpg?easyrotate_cache=1192055701)
Just over the stairs on the right hand wall notice they had hewed into an offending log in a few places to let the furring strips in, somebody originally hewed thick on that log. In the 70's it was fashionable to strip the furring and expose the logs again. They found a sword in a chink joint during that remodel. The house had been furred out and gentrified in 1865, stash that weapon.
(https://forestryforum.com/gallery/albums/userpics/10017/pdgtrails.jpg?easyrotate_cache=1192055715)
The chinked round log style you described was popular around the 1920's-~40's kind of started by the rich city folk having mobility and building getaway camps and then others just liking the style.
Quote from: Mooseherder on March 17, 2021, 09:52:43 PMTime saved must have been a factor.
I don't think I've ever seen a building built with logs hewed on all 4 sides and chinked. Is that even a style? And if there weren't a significant gap between logs that would seem to make it really hard to get the chinking between logs compared to logs that gradually curved together.
Rather than thinking that hewing just 2 sides saved time compared to hewing all 4 sides, I was thinking that hewing 2 sides cost a lot more time than hewing none.
My 14 year old son is currently in the process of building a roughly 10'x10' cabin/playhouse out of round logs. He has some experience hewing, but neither he nor I saw any reason to hew any sides on the logs he's using (mostly tulip-poplar.) I'd definitely like to understand any practical advantages of hewn surfaces that I might be missing, though.
The conventional rational for squaring up the two outward faces I always get are removing vulnerable sap wood and/or a measure for readily shedding water, in the case of the weather side.
At my place there are examples of two-sides squared and completely round, as well as combinations of both in a single structure all softwoods and the only consistency I've been able to see till now is the prominence of each building, determined by use or precision of the construction.
(https://forestryforum.com/gallery/albums/userpics/64601/image~18.jpeg?easyrotate_cache=1616037925)
I don't know that the "extra effort" in and of itself translates necessarily into
greater durability, that's not self evident from what I see. The question of round or flattened seems to be determined primarily by visual considerations. In other words it is a matter of ego. In the building pictured which I'm calling the bunkhouse, it's the two prominent walls, strictly in terms visibility on approach, that are worked flat, the more out-of-sight wall left round.
Yes, times are different. When built, log house = poor. As soon as they could afford it the logs were covered inside and out. My first house was a farmhouse more than 100 years old. The central structure was a hewn log home (hewn on all four sides) with three surrounding additions (all stick framed). When we stripped and exposed the logs inside it was lime and sand chinking, several coats of lime whitewash in various colors, furring strips with lath and horse-hair plaster, several colors of milk paint, at least three layers of wallpaper, and cheap paneling. unfortunately no treasures, but lots of old newsprint for insulation.
The logs were massive! several had out-of-place joinery and some charring, indicating they were recycled from a barn that burned. If I remember correctly there were only 6 logs to reach the 9-foot ceiling. Of course nothing was straight... I used to tell people the house was built before they invented the straight line.
There are 2 problems with tulip poplar. First ppb's love it, so I would borate it heavily. Second, it tends to open up large checks in a timber as it dries. It was commonly used here at plate levels that had a lot of notching because it was easier to work. By hewing the 2 faces it pretty much guaranteed that it would open up that large check on one of the visible faces. For full round logs I would kerf the bottom edge of the logs to encourage that check to form in the chink joint.
This is a pic of one of the large face checks in the upper log compared to the white oak logs below it;
(https://forestryforum.com/gallery/albums/userpics/10017/poplog3.jpg?easyrotate_cache=1219783593)
The bark should start slipping in the next month or two.
For chinking, portland cement based chinks trap moisture and encourage rot. Lime/sand based chinking is breathable and discourages bugs and rot.
We were having a discussion on plaster and lime in another thread and I've been playing with burning limestone in the woodstove and slaking the small amount in a mason jar. Fun but very small scale, I've made enough to set a brick :D. You can buy bagged type S hydrated lime for plaster work.
(https://forestryforum.com/gallery/albums/userpics/10017/slacklime.jpg?easyrotate_cache=1616066350)
I've never seen it done any other way. Not only would it have been double the work for each log, but the wall would require more pieces, since each one would not be as tall.
Around here, 18th, and early 19th Century houses were built from hewed beams that had been sawn on "one side". I'm the only person that I've heard come up with a theory why.
Hewing is a Lot of work. There were professional hewers that did nothing else. Hewing also leave a big pile of mess that's not really good for anything.
My theory about these sawn on one side house parts is that they hewed the log in the woods to square. That would make the piece a lot easier to move out of the woods than a whole log, with animal, or human power being all that was available, and also left all the mess of noggles in the woods to rot, that no one had to bother to move.
Now that you've paid someone for a couple of hours of work to square up a log into a beam, if you try to split it, you're going to lose some, and also have a Really rough side.
My theory is that they could take the, now lighter, squared log out of the woods to a pit, and saw it down the middle, not losing a single piece.
Speaking of lime, I had used up all my Type S putty, so not being able to buy a fresh bag anywhere around here, I paid a premium price to order one off Amazon. It just came yesterday, and is nice fluffy stuff, from Graymont. I'm surprised you can get the Limestone hot enough in a wood stove.
(https://forestryforum.com/gallery/albums/userpics/35437/tombroadaxe.JPG?easyrotate_cache=1616074600)
This weight reduction is a good point. I have taken excessive wood off a stem just in order to make it manageable for me to get the stem onto its staging for further working. Also timbers shipped from the Canadian woods to Europe in that period were squared up at the earliest moment in order to save space and so they wouldn't roll around on board the ships, to be milled further once at their destination where the technology was at hand. I've also flattened two sides to facilitate ripping with pit saws, the practicality being in, once again, significant weight reduction for positioning the wood and providing a stable surface for anchoring the stem.
Well I don't know about the waste being useless. It makes great firewood and it is years since I have had to split kindling. All of the waste from axing is to me very useful unlike sawdust from saw milling. On occasion we've even separated and bundled the waste for sale and brought in a bit of cash.
I do hope we get to know the results of DonP's lime burning, does the result perform and so on and so on.
Quote from: Don P on March 18, 2021, 07:17:29 AMThere are 2 problems with tulip poplar. First ppb's love it, so I would borate it heavily. Second, it tends to open up large checks in a timber as it dries. It was commonly used here at plate levels that had a lot of notching because it was easier to work. By hewing the 2 faces it pretty much guaranteed that it would open up that large check on one of the visible faces. For full round logs I would kerf the bottom edge of the logs to encourage that check to form in the chink joint.
Is it at all reasonable to build with round tulip-poplar logs without borate or any other treatment if my son (in this case) uses another species for the sills and floor joists and first couple wall logs such that all the tulip-poplar logs are at least a couple feet from the ground and he extends the eaves and gable ends out 18" or more beyond the wall logs (and uses another species for those logs that will extend out to the edge of the roof)? That's his rough plan at the moment. He's already collected and mostly de-barked most of the tulip-poplar logs he's planning to use, but so far wild cherry (and just two or three red-cedar logs) is all that he's actually used.
And what are the issues with checking? I assume it's more than just cosmetic? Is there a simple way to kerf the bottom edge of a round log with hand tools? I assume a chainsaw would be the normal way to do that.
Quote from: Tom King on March 18, 2021, 09:34:27 AMMy theory about these sawn on one side house parts is that they hewed the log in the woods to square. That would make the piece a lot easier to move out of the woods than a whole log, with animal, or human power being all that was available
You described almost exactly what I did with some trees I needed to fell recently and that I didn't want to let go to waste, as well as my reasons for doing it that way. My son and I hewed them more or less square, and then I used a combination of scoring and slitting them in half and ripping them in half with a chainsaw. So I now have several beams hewed on 3 sides and sawn with a chainsaw on the 4th.
I've seen PPB's described as a slow moving epidemic. I don't know how high they fly but it is at least 35'. A few rows of another species isn't going to protect them. They pretty much hit everything, inside and out. They much prefer sapwood to heartwood, they're starch eaters.
Kerfing is usually done with a chainsaw or a skillsaw. Aesthetics is one part but checks also invite water and bugs into the log. Part of this is how long does this need to last. If its a relatively temporary structure then no worries. If you are trying to build it to last these things will help it out.
The woodstove is way too cool for good lime burning so I'm not sure of the quality of this stuff. It burns about 1/8 or so deep at a time, that slakes the next day and then I throw them back in for another round. I was just playing around with it kind of debating whether to set up a lime rick burn at the museum on a demo day to make some for plastering the basement and mortaring a chimney rebuild. To bring that tangent back on topic, I'm guessing a chinking mix would be something around 1 part lime to 3 parts sand?
When we chainsaw milled a 60' long beam in the woods we only did 3 sides, I got worried about breaking it on our way out and to the jobsite so left it deep and carried it that way. But even up to 40' I wasn't worried so I doubt strength was a typical concern back in the day.
I think I have some chink pics in my gallery,
We called this one cob and daub. They had used clay (which was riddled with tunnels and nesting spots) then lime plaster. Then cement really poorly detailed, instead of tucked under to shed water they kind of made gutters to invite water in and hold it against the logs.
(https://forestryforum.com/gallery/albums/userpics/10017/cobchink.jpg?easyrotate_cache=1192055667)
Chip and dip. This one looked like splits from firewood stacked. Hot mixed lime and sand. That is whitewash on the logs. Notice the beaded floor joist, very common, and you are seeing where it had lath and plaster done at some point, that is also the top of a furring strip from that period.
(https://forestryforum.com/gallery/albums/userpics/10017/chipndip.jpg?easyrotate_cache=1192055664)
To continue the alliteration :D, flake and slake.
The remains of more lime/sand daubing, some wood strip chinking in the row above the limestone flakes and a furring strip from the siding remodel on this one. There was the remains of an Icy Ball fridge inside and somewhere I have a US cavalry trace chain that was in the debris. The flakes of dolomitic limestone there as well as the chimney were chopped out of the adjoining riverbed. This is the same limestone you see all the way up 81 from around Abingdon up through the Shenandoah Valley and into PA. Oh, actually its some of those chips I've been cooking in the woodstove, I bought this one for the logs, my wife saw the chimney and I had to bring that home too :D
(https://forestryforum.com/gallery/albums/userpics/10017/stonechink.jpg?easyrotate_cache=1192055736)
It's not so much the 900 deg. needed to convert the limestone - significantly below what's required for Portland cement - but maintaining that temperature constantly for 24 hours.
The durability of poplar - it's susceptibility to bug damage and so on and so on - must be conditional. This is a wood used as an alternative to oak in France for horse stables because the urine will not discolor it.
Quote from: Don P on March 18, 2021, 07:17:49 PM
I've seen PPB's described as a slow moving epidemic. I don't know how high they fly but it is at least 35'.
If I may. what in the heck are PPB's?
Quote from: Sedgehammer on March 19, 2021, 02:40:58 AM
If I may. what in the heck are PPB's?
Powder Post Beetles.
Quote from: Tom King on March 18, 2021, 09:34:27 AM
I've never seen it done any other way. Not only would it have been double the work for each log, but the wall would require more pieces, since each one would not be as tall.
Around here, 18th, and early 19th Century houses were built from hewed beams that had been sawn on "one side". I'm the only person that I've heard come up with a theory why.
Hewing is a Lot of work. There were professional hewers that did nothing else. Hewing also leave a big pile of mess that's not really good for anything.
My theory about these sawn on one side house parts is that they hewed the log in the woods to square. That would make the piece a lot easier to move out of the woods than a whole log, with animal, or human power being all that was available, and also left all the mess of noggles in the woods to rot, that no one had to bother to move.
Now that you've paid someone for a couple of hours of work to square up a log into a beam, if you try to split it, you're going to lose some, and also have a Really rough side.
My theory is that they could take the, now lighter, squared log out of the woods to a pit, and saw it down the middle, not losing a single piece.
Speaking of lime, I had used up all my Type S putty, so not being able to buy a fresh bag anywhere around here, I paid a premium price to order one off Amazon. It just came yesterday, and is nice fluffy stuff, from Graymont. I'm surprised you can get the Limestone hot enough in a wood stove.
(https://forestryforum.com/gallery/albums/userpics/35437/tombroadaxe.JPG?easyrotate_cache=1616074600)
The axe looks Swedish. Single or double beveled?
Single bevel. No maker marks on it. Came out of a junk shop 40 years ago. I doubt it's Swedish. It is a nice one though-has a nice sweep on the back, and a curve to the cutting edge.
1 to 3 was typically the mix called for in interior layers of brick in foundations. The outer layer called for 1 to 2. I have a link saved somewhere (not at hand right now-probably in an old hard drive), where George Washington wrote the specifications, in great detail, for building a Glebe House in the Parrish where we lived (Truro, I think). Those were the ratios he called for in mixing the mortar for the brick foundation.
I'd mix a chinking mix richer than that, but really, you have to play with it on a trowel to see how it works. It needs to stick together, as well as to what it's being used with. Too lean, and it just supports weight, if it doesn't get wet.
Talking about the hewed on two sides thing, I worked on an 1850 house where two thirds of the ceiling joists were hewed on one side, and sawn on the other, and the other third were sawn on two sides. I figured the same about hewing the log in the woods, but then they sawed three pieces out of it. They were a little over 2-3/4" thick, so I think that was a good representation of the beginning of starting to use smaller framing pieces. I have pictures somewhere.
Typically for the standardized mass produced early American broad axes the blade flair begins immediately at the eye's termination and it's the shape of the blade that gives an axe its designation, Pennsylvania, New Orleans, Canadian... (I in no way vouch for the accuracy of information presented in this (https://www.fs.fed.us/eng/pubs/htmlpubs/htm99232823/page02.htm#broad) link) Of course there is an infinite possibility for deviation when the axe is a one-off or from the hand of a local blacksmith, probably a reflection of background or training. I see yours though has the extension after the eye and then the broadening of the blade and that is what you see even in the new Swedish axes, Gransfors, Wetterlings, Hult and so on and so on. Anyway it's an interesting version for sure. Just by way of coincidence, I held in my hands an old squaring-up axe yesterday in a shop in Delta and was impressed with the handle, so slim, a nice upward sweep a handy swell, (what was left of it). I could imagine it making nice work on some old cabin walls. Maybe I should have bit the bullet and brought it home along with the bottle jack they had at a very good price.
Quote from: NCEric on March 17, 2021, 09:10:23 PM
It seems like the typical old log building around where I live in the western Piedmont of North Carolina is made from southern yellow pine logs hewed very roughly flat on the two sides facing in and out but not the two sides facing the logs above and below. This seems to include even buildings that were never lived in but were just for farm use. A few weeks ago I saw a couple interesting exceptions. One was a white oak log building that had presumably been chinked at one point, so similar to the standard log buildings around here in that respect -- the logs weren't tight together like I think of Scandinavian or northwestern US log buildings -- but the logs were round, not hewed on any sides. The other building was a hybrid of the two styles I've just described: the first 5 or 6' nearest the ground were unhewed white oak logs and then from there up the building was completed in pine logs hewed on just two sides. What's the point of hewing the two sides of the pine logs? Why go to the trouble? Was it just for the aesthetic? But obviously it wasn't just for the aesthetic on the hybrid building I described, because only the pine logs but not the oak logs were hewed.
A couple of simple maybe why comes
1. Space. Flat surface on the inside resulted more space and easier using of space on the interior since it's 'flat'. Rain ran of faster if it was flat on the outside vs round
2. Height. Round logs stack up faster and that area can be filled with 'chink'. The chink served 2 main purposes. One it was a medium to stop are flow between the logs into the home. The width of the area that was filled with the chink resulted in a larger possibility in cutting down on air transfer vs if the logs were square to each other. Secondary was it was easier to fill that area with chink then cutting it.
It looks more like 18a in that link. I'll try to remember to take a picture, when I go to the shop where it is. The handle came off ebay, years ago, after one I made from a crooked Hickory limb never really worked that good.
I use a complete array of old Stanley planes too, but I've never looked up what age they are, or even what Type number. I don't think in words, and wouldn't remember anyway. I just need to produce work to make a living, and am always thinking about what to do next. Often, I can't tell you what I did yesterday.
Also I have some of those iron planes but no idea how they are identified officially. "Pass me the joiner" 's all I'll say. :D
These subtle aspects of the grip/handle, angle, sweep, diameter, length... will determine whether or not the axe is even functional. I rarely mess with an old handle on a broad axe if it can avoided.
More diversion from the topic to lime, excuses. I was just reading on the recent completion of a restauration of the second oldest Spanish church in the Americas and this quote on the lime, "... A lengthy process that requires aging the mixture."
My understanding from what I've read, you guys have a better understanding than me, when making lime putty from quicklime, the longer it is slaked the better it gets. The ancient Roman lime, made from limestone from the dolomites, high in magnesium, when burned making magnesium oxide which is slow, was required to be 3 years old.
The burn temp needed to drive off the CO2 from the limestone to make good quicklime, or I'd bet if that was a Florida mission, shells or coral, is 900°C, ~1650°F, that is a toasty fire. In coastal SC and GA they built back in the day with tabby, an oyster shell based lime "concrete". I think the technique came from the Spanish?
The chinking and mortar I've seen was "hot mixed". The freshly burned quicklime was mixed with the sand, water was added and it was slaked, I believe just overnight, then used. When you look at mortar or chinking here it has visible bits of unslaked limestone showing. It didn't get the lengthy long slaking that would have broken it all down into a nice smooth plaster quality putty.
Edit, dragging us way off topic, I just googled tabby and found a good article.
Tabby (atlantapreservation.com) (http://www.atlantapreservation.com/buildingmaterials/TabbyInfo.pdf)
Slaking an extended time is new to me. Since I've never had much prospect at even getting my grubby hands on any reliable quicklime I never did look much into the slaking process. No, I only know of two time related elements of lime processing, letting the putty stand under water for up to 40 years, (a form of slaking?) and the lime and sand mix standing some months just prior to use, either as a mortar or for pointing up, so that would be somewhat similar to use in chinking log walls.
When I began going through your article my first thought was this tabby is something like tadelak which is common in North Africa. Could it be that the processes are related? Further on in the article the distinctions were more clear but it seems obvious that the origins predate use by the Spanish and are African, a place where different plastering and similar construction forms are highly varied and developed.
I've bought every book I could find on Lime for masonry, and plaster. I reread parts of one that was reprinted from French by a guy who tested several versions in 1818. They knew that it absorbed CO2 from the atmosphere, but called Carbon Dioxide Carbonic Acid. He went into saying the different theories of different methods seemed to be written by people who believed the way they had been doing it was the best way, but he did his testing because he could never find any evidence that anyone had done actual comparisons before.
He said that the putty made directly from Quicklime had a higher initial adhesive strength, but beyond that, I don't think it lasted any better. The trouble with any kind of testing is that it would need to be exposed to the elements for at least a couple of centuries, before you really know.
A book I have from the early 20th Century, has a photograph of workers in all white clothes, and cute white hats screening Hydrated Lime from bags into a large vat. They mixed it ahead of time on the job, but didn't give any recommended amount of time. I think that one said a couple of weeks, but I have a hard time keeping all the different sources of information clear on stuff I read years ago. I just came up with something that works good for me, after Virginia Lime Works did me a favor, and went out of business, forcing me to learn more about it.
In some other book, it said the putty needed to be made 3 months ahead of when it was used. That's what I've gone by, and try to keep some in 5 gallon closed buckets on hand. I can't tell any difference between 3 months, and 3 years, but there is a Big difference between anything mixed with putty, versus buying anyone's dry mix in a bag.
I believe the Type S, sold by Graymont under Western brand, is pretty close to what the Romans used. They just dug it up from being processed for them by a volcano. Some people say humans forgot how to many concrete between the Romans, and the mid 19th Century, but the Romans didn't really know how to manufacture it. They just dug up what worked.
My assumption was that quicklime form was really the only option until relatively recent industrial and logistical alternatives were available.
I believe that's right.
A fanciful representation of the basic process we are going on and on and on about.
Les feux de Guédelon - saison 1 - épisode 4 - YouTube (https://youtube.com/watch?v=HFNUCBSPVDg&feature=share)
(https://youtube.com/watch?v=HFNUCBSPVDg&feature=share)
Here's another one, and probably a represents the way it was done here, most of the time. There were not too many Lime Kilns in this part of the country. The only one I know is up near Lexington, Va.
There are Many places around the world named Limerick. This is called burning a Lime Rick.
Building George's House: Lime Rick Burn - YouTube (https://www.youtube.com/watch?v=tDuDGyYA7pQ&t=100s)
Eric, sorry, we've wandered, feel free to bring us back around any time.
Lime kiln road is on my way to work from here but the kiln is long gone. I'll try to find and post a pic of one not too far from here built near an old Irish style brick mansion. Many old iron furnaces were last used to burn lime after cold blast went to Bessemer iron, but most limestone here was small rick burns both for building and soil sweetening from what I can tell. Dad remembers digging in the marl pit at home in eastern NC for field dressing when he was a boy.
The volcanic ash the romans used in their opus caementicium, cement work, was replacing part or all of the sand. Other than that it was a mix of quicklime and aggregate, which for them was usually rubble, placed, rammed in and the cement paste was poured and tamped. Vitruvius in his "Ten Books on Architecture" called out a 3:1 mix of lime to sand ("pit sand", volcanic ash) for most work, 2:1 for marine.
From my understanding they learned to burn lime and make plaster centuries earlier when trying to mimic Greek building. The tuff that was more readily available to them as a building stone is not particularly pretty, so they began experimenting with plastering over the rough coarse stone. Plaster itself is prehistoric, probably limestone in a fire ring that burned, it rained, and a workable paste was formed. There's all grades on the way to "ideal" but many that are more or less serviceable.
They had a good understanding of what they were doing. In the dome of the Pantheon (the 2,000 year old, largest unreinforced concrete dome in the world) they lightened the dome as it rose to lower the hoop stress, thrust, by going from 19' thick using brick and dense tufa aggregate at the base down to 5' thick and light tufa and pumice aggregate to make lightweight concrete by the top. Aside from the thickness difference they had cut the density of the concrete itself in half from base to top. That building is really a study in some pretty complex engineering with relieving arches and buttressing that foreshadows later cathedral work but they had concrete down by the time of Hadrian.
Not far from where I lived in holland there is a church tower built with this tuff stone which was a common enough material in the Middle Ages. It really is a but ugly material and's understandable that anyone would want to plaster it. If plaster wouldn't have been around already, this would have been a reason itself to invent it.
I had to review a video I have on Greek and Roman construction to get some of this sorted out and figured it might be of some historic interest.
The Romans learned stone masonry construction from the Etruscans who learned from the Greeks. This was dry laid ashlar (coursed) finely fitted rectangular stonework held together with iron clamps (I've seen examples of lead pours into keys as well). It was highly skilled work as the stones had to be perfectly smoothed for full bearing to avoid cracking over high spots in large structures. The Romans plastered over their ugly stone to imitate marble.
The next development was to apply a thin layer of the same plaster as a lime/sand mortar between stones to allow less well fitted stones to be used. This sped up construction and sealed the joints.
This works fine, lime plaster is air setting, CO2 from the air hardens the hydrated lime back to calcium carbonate, limestone. But, if you try to cast a large mass of plaster the surface hardens and seals the core from the air and it never fully hardens.
About the third century BC they discovered, or rediscovered, that using volcanic sand/ash would harden to a solid that was 5 times stronger than the regular lime/sand mortar. The silica in the pozzolana combined with the hydrated lime to form calcium silicate hydrate which needs no air or CO2 to harden and in fact can set underwater. That compound is what comprises ~50-70% of modern portland cement. The large aggregate in roman cement is broken bricks and tiles, chunks of rubble and stone, and broken amphorae.
As the technology advanced they first built uncoursed fitted stone walls to form opposite faces of a wall, as forms, and poured in mortar, tamped in rubble, repeat in layers till full, opus incertum.
Next they laid up the walls with premade small diamond shaped stone blocks for the facings and filled with concrete as before, opus reticulatum. Less skilled labor (slaves and unskilled workmen). They were conquering more territory and building vast infrastructure.
About the time of Vitruvius 1st century BC they began using terra cotta bricks, mass production. This evolved from experimenting using roofing tiles in wall construction. The square bipedales, 2' square, were cut diagonally into triangles, laying a running bond with the points of the triangles facing the core of the wall, excellent toothing! and pouring the core. Very fast, looks good, much of the work is low skilled.
Going back to opus incertum something else was going on. They had the precisely fitted stone arch figured out but it took lots of highly skilled labor. They had figured out the tied wooden truss for spanning large buildings without rows of internal columns but wood was subject to decay and insects. By extending the arch they could make barrel vaults but the work of fitting that much stone was extremely time consuming. If they wanted a crossing vault building a groined vault in stone is a bear. Wooden formwork is fast and making groined vault centering forms is pretty easy. Pour concrete over the forms and Bob's your uncle. In 193 BC they needed a new trans shipment facility in Rome alongside the Tiber river and built a warehouse that had 50 barrel vaults facing the river for 1600 feet. The vaults stepped up the slope for 200' and were crossed by I think eight 1600' long barrel vaults that ran the length of the building. At each of the steps up the slope the vaults formed an eyebrow window that daylighted the interior. About 300,000 square feet under roof, 2 centuries before Christ! Porticus Aemelia.
As you climb the slope from the warehouses towards the city there is a mountain of broken amphorae rubble. The capitol was an importer, they had nothing to export but soldiers, politicians and war. The shipping jugs were one way containers and used as aggregate, except for the olive oil jugs which were too oily for construction so they threw them out back and kept the front yard looking good.
The brickmaking opus testaceum (tes-tock-eee-um) period really took off around 100 AD. They were making them by the millions and branched out into hexagonal floor tiles, terra cotta water and sewer pipes and rectangular heating tubuli, gotta keep the big bath houses warm. The bricks were stamped with the maker or legion (for military construction) and emperor's name. If you can find a stamp you can date the building.
A really interesting series of lectures from Stephen Ressler, a West Point professor of engineering.
Back on tulip poplar log walls- The modern log home industry is often located nearby a plentiful supply of those trees as the mostly replaced the American Chestnut after the blight event. They tried and now avoid then due to checking as it's poor customer relations overall not that they don't function OK structurally. In historical hewed logs houses thats a whole nuther thing. They avoid the poplars and go for some type of regional pine with a handfull of niche market oak & cedar logs walls.
Once I picked up a load of lime flour and the shop had a partial bucket of a kind of flaky baked clay shards, a byproduct of soft baked tiles or something similar they called "graffel" which I got for experimenting. The shards were small maybe 1/8', flat and very sharp edged also very light in weight. I used them for agrigate in a poured lime floor, the extra I dumped out back on the ditch so I was able to observe how it set. This material hardened more than other lime surfaces and makes an excellent floor. A lime floor like this needs no expansion joints and cracks are inconsequential because lime has its self-repairing character. The floor, subject to periodic flooding in times of heavy rain dries almost immediately, never pooling and even continues to harden, the water in fact has a positive effect.
Quote from: Don P on March 22, 2021, 09:33:55 AMEric, sorry, we've wandered, feel free to bring us back around any time.
Wander away as far as I'm concerned! It's all interesting, and it seems like the original discussion had a very fair opportunity.
Here i thought "you put the lime in da coconut "
Hopefully there is a route back. I thought maybe we Might be on the way once DonP brought up the stone chinking but I'm confident about getting there. It's all somehow related and squaring up logs with axes is more interesting to me anyway. I mean you could just as easily ask why are mortared stone walls most often made with a flat side.
Quote from: NCEric on March 24, 2021, 10:29:22 PM
Quote from: Don P on March 22, 2021, 09:33:55 AMEric, sorry, we've wandered, feel free to bring us back around any time.
Wander away as far as I'm concerned! It's all interesting, and it seems like the original discussion had a very fair opportunity.
Quote from: Don P on March 23, 2021, 09:44:45 PM
I had to review a video I have on Greek and Roman construction to get some of this sorted out and figured it might be of some historic interest.
The Romans learned stone masonry construction from the Etruscans who learned from the Greeks. This was dry laid ashlar (coursed) finely fitted rectangular stonework held together with iron clamps (I've seen examples of lead pours into keys as well). It was highly skilled work as the stones had to be perfectly smoothed for full bearing to avoid cracking over high spots in large structures. The Romans plastered over their ugly stone to imitate marble.
The next development was to apply a thin layer of the same plaster as a lime/sand mortar between stones to allow less well fitted stones to be used. This sped up construction and sealed the joints.
This works fine, lime plaster is air setting, CO2 from the air hardens the hydrated lime back to calcium carbonate, limestone. But, if you try to cast a large mass of plaster the surface hardens and seals the core from the air and it never fully hardens.
About the third century BC they discovered, or rediscovered, that using volcanic sand/ash would harden to a solid that was 5 times stronger than the regular lime/sand mortar. The silica in the pozzolana combined with the hydrated lime to form calcium silicate hydrate which needs no air or CO2 to harden and in fact can set underwater. That compound is what comprises ~50-70% of modern portland cement. The large aggregate in roman cement is broken bricks and tiles, chunks of rubble and stone, and broken amphorae.
As the technology advanced they first built uncoursed fitted stone walls to form opposite faces of a wall, as forms, and poured in mortar, tamped in rubble, repeat in layers till full, opus incertum.
Next they laid up the walls with premade small diamond shaped stone blocks for the facings and filled with concrete as before, opus reticulatum. Less skilled labor (slaves and unskilled workmen). They were conquering more territory and building vast infrastructure.
About the time of Vitruvius 1st century BC they began using terra cotta bricks, mass production. This evolved from experimenting using roofing tiles in wall construction. The square bipedales, 2' square, were cut diagonally into triangles, laying a running bond with the points of the triangles facing the core of the wall, excellent toothing! and pouring the core. Very fast, looks good, much of the work is low skilled.
Going back to opus incertum something else was going on. They had the precisely fitted stone arch figured out but it took lots of highly skilled labor. They had figured out the tied wooden truss for spanning large buildings without rows of internal columns but wood was subject to decay and insects. By extending the arch they could make barrel vaults but the work of fitting that much stone was extremely time consuming. If they wanted a crossing vault building a groined vault in stone is a bear. Wooden formwork is fast and making groined vault centering forms is pretty easy. Pour concrete over the forms and Bob's your uncle. In 193 BC they needed a new trans shipment facility in Rome alongside the Tiber river and built a warehouse that had 50 barrel vaults facing the river for 1600 feet. The vaults stepped up the slope for 200' and were crossed by I think eight 1600' long barrel vaults that ran the length of the building. At each of the steps up the slope the vaults formed an eyebrow window that daylighted the interior. About 300,000 square feet under roof, 2 centuries before Christ! Porticus Aemelia.
As you climb the slope from the warehouses towards the city there is a mountain of broken amphorae rubble. The capitol was an importer, they had nothing to export but soldiers, politicians and war. The shipping jugs were one way containers and used as aggregate, except for the olive oil jugs which were too oily for construction so they threw them out back and kept the front yard looking good.
The brickmaking opus testaceum (tes-tock-eee-um) period really took off around 100 AD. They were making them by the millions and branched out into hexagonal floor tiles, terra cotta water and sewer pipes and rectangular heating tubuli, gotta keep the big bath houses warm. The bricks were stamped with the maker or legion (for military construction) and emperor's name. If you can find a stamp you can date the building.
A really interesting series of lectures from Stephen Ressler, a West Point professor of engineering.
2 things.
1. How do you find time to work? You have a vast knowledge of so many topics and the time/study to learn all of this, plus work. You are a valuable resource to the forum!
2. I think the concrete they made is still getting harder to this day and we have only just now figured out how they made it. I think I remember reading or watched a show on it.
Exact composition and process for Roman cement is still lost.
https://unews.utah.edu/roman-concrete/ (https://unews.utah.edu/roman-concrete/)
Ahh k. That's the exact same article I read. Thanks for posting that. I had forgot that part on it.
I just returned to the station from a house fire. It was an old 1800's log cabin which was hewed flat on both sides. The outside was sided with old asbestos tile siding and then had vinyl put up over that. I'm not sure what was on the inside, because the fire had been burning for a while before we got there. I imagine that it had paneling. It was a shame to see it go up in flames. Could have been really neat restored to former glory.
Man, I always hated the ones where we had to go through 3 layers of wall to find the fire. We did an old hotel fire (late 1800's original construction) where we had to open 3 different ceilings to get into the void space. That was an all nighter and took a lot of gear out of service for repair. We were cutting scuttle holes in the floors upstairs to get the water weight out of the building and filled every saw chain with old carpet. Walls over other walls, a mess and a total loss.
Had another one, small farmhouse type (around 1860) that had three additions that met in one spot where the electrical service came in, which is also where the fire started (10KV backfeed into the panel) and blew the fire up the wall. Those old timbers took it hard and it was a bear to expose and wet it all down. We were worried about what we might cut and bring a roof down or have it shift. We actually saved that house and I pass it often thinking of that February night during a heavy wet snowstorm when I was the only guy on scene trying to knock that thing down.
Sounds like you lost that one in spite of the log construction? I am guessing there wasn't much of a foundation to save either?
As near as I could tell it was a rubble stone foundation with sort of a crawl space. Floor joists were hewn logs too.
The second fire of the day was a mobile home. It was not made of any kind of logs. Barely had any wood in it at all.
Quote from: firefighter ontheside on April 01, 2021, 05:54:47 PM
As near as I could tell it was a rubble stone foundation with sort of a crawl space. Floor joists were hewn logs too.
so much for my theory on egoism. It's like I always say, squaring up with axes is just plain fun, that's it.
I swung by the old lime kiln on our way home this afternoon, it's grown up more, I barely missed missing it :D
(https://forestryforum.com/gallery/albums/userpics/10017/IMG_6478.jpg?easyrotate_cache=1619140016)
My understanding of this type is the limestone was broken up into fist sized chunks and loosely loaded into the open top of this furnace. It is built into the bank and the top is at ground level above.
This is where I'm not sure but I think it was fired through this hole and the draft carried the flames and heat in and up through the limestone. After it cooled the burnt quicklime was raked out through this hole. I think it is actually a little taller opening, it has just partially filled in over time. But... some of these were fired by layering limestone and fuel wood together and igniting that, if that is the case this is just the air intake and burnt lime discharge. Looking at it now, I'm kind of leaning that way, I see no smoke marks around this opening and that is a timber header over the opening.
(https://forestryforum.com/gallery/albums/userpics/10017/IMG_6475.jpg?easyrotate_cache=1619140377)
This is the nearby house I'm sure the kiln was built for. There was a young family living there about 10 years ago and working on it, it looks unoccupied again :-\
(https://forestryforum.com/gallery/albums/userpics/10017/IMG_6479.jpg?easyrotate_cache=1619140882)
I burnt- maybe an overstatement- some plaster I'd hauled off, slaked it and mixed in a mason jar then forgot about it moving on to figuring out ratios for clay plaster. Checking recently the slurry'd dried, bonded and hardened good. I guess lime is reusable, the theory, reversing the original reversion of the calcium equation.
Yes it is, you just restarted the lime cycle by going back to quicklime. Cool :)
You know, I've heard stories of these poor saps manning the lime kilns 24 hours a day who've fallen asleep atop the kiln where the fuel is fed and rolled in. No doubt more myth than reality based purely on the suggestion of a set-up like that.
Neat picture of the old furnace. I've seen another very similar to this in Floyd VA. Same scenario, built beside a steep hill to access the top but taller. I was told it was used to smelt copper although could have been used for limestone as well.
Hmm, you do have Copper Hill, could be and it sounds more like a furnace than a lime kiln.
This is a pic of one of our iron furnaces, they are considerably larger and taller and have a brick lined cone on cone shaped interior. They also have 3 arches on the sides at the bottom. On the front is the tapping arch with slag arches and provision for the wind belt (air blast) on the sides.
The shed here is over the tapping arch and casting floor. Back in the day there was a brick top a bit higher and the narrow guage ran on the hill behind it. there was a wooden bridge from the hill to charge it with ore, charcoal and limestone to flux the slag. I've seen old pics of this one with railroad and locomotive castings around.
(https://forestryforum.com/gallery/albums/userpics/10017/noblefurnopt.jpg?easyrotate_cache=1192055706)
This is standing inside another one a few miles from that furnace. I'm standing at about the level of the bosh, the widest part of the cone on cone shaped interior. The hottest part. You can see the lining collapsed which was probably the death of this furnace. Some of the salt pots for Saltville came from this furnace.
(https://forestryforum.com/gallery/albums/userpics/10017/bosh.jpg?easyrotate_cache=1192055658)
With the advent of hot blast, coke and the Bessemer converter these old charcoal furnaces were idled. More than a few continued for awhile burning lime.
I've heard stories of colliers, charcoal makers, climbing onto the earth covered pile to patch a smoke leak and falling into the hot charcoal.