Re: historic hewing questionnaire
[Re: northern hewer]
#34229
08/17/17 02:19 AM
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northern hewer
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hello everyone tonight
Its been a while sorry-----but lets try and continue a little further--
You know, this old crude mill is pretty interesting, don't you think?, even now as I ponder its intricate parts, it seems even more complicated than when I operated and maintained it--
Well we were talking about the moveable bunk lets continue--
Now we have a general idea about its shape there is one more important aspect, which is the replaceable inserts, on the upper leading edge of the bunk, on which the log to be sawn will rest.
There are 2 of them one on each side of the slot, they are in dimension 4 by 6 inches, bolted and well secured in position, their position being approx. 1.5" apart
These inserts are cut into the upper surface of the bunk allowing enough depth to accommodate wedges for levelling their upper surfaces
Now I say levelling well that is misleading, because a good millwright will understand that under the weight of the log, when one is eventually loaded, the bunk will deflect down slightly, causing a vertical cutting error, so to compensate one must slightly elevate the end of the insert closest to the blade
To facilitate this measurement of squareness pull the moveable bunk ahead until it is abreast of the vertical blade and is situated between the two replaceable inserts
Now placing a square against the blade and on top of the insert, one should observe that the top of the insert is out of level slightly by about 1/8" on the 24" blade of the square
Now this will work for most ordinary logs, but might not be enough for very heavy logs that may cause more deflection in the bunk
well have to go for now
enjoy--like to hear some comments if you are enjoying--
NH
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Re: historic hewing questionnaire
[Re: northern hewer]
#34230
08/18/17 02:13 AM
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northern hewer
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hello everyone tonight
To round out a complete picture of this bunk, ready to work will consist of the hardware items, that are quite massive and heavy--2 separate cast iron dogs, that are fastened to the moveable bunk, on each side of the slot in the bunk, so that they can be hammered into the end of the log with a wooden commander--the dogs are not easy to describe but I will try--they are shaped in a mirror image of each other--each one shaped like an upside down "u"--the "u", with a spur on the leading top edge closest to the blade--this spur is 2" in height and 1\2" thick of steel and sharpened along its full length using one bevel, the "u" is about 14" in height, with a spread of its legs about 10", and constructed using 1.5" wrought iron stock in the 1800's by a good blacksmith.
The bottom of each leg has an eye with an associated eye and bolt intertwined together for fastening to the bunk, here again there is usually not a thread and nut but rather a slot with a tapered key fashioned into the end of the bolt
Well have to go now
hope you are enjoying any questions just ask NH---Richard Casselman UE 14572
Last edited by northern hewer; 08/18/17 02:16 AM.
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Re: historic hewing questionnaire
[Re: northern hewer]
#34278
11/13/17 02:54 AM
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Posts: 1,193
northern hewer
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Hello everyone
Again it's been quite a while but things are moving slower in my world now, but just as enthused about the historic world of wood working and fashioning things by hand using old tools.
Before I forget a merry Christmas to everyone, and I hope good health to all as we enter the new year
Over the last while I have been trying to describe the workings of a Muley mill quite a challenging feat I am finding out
Oliver Evans also tried to describe the workings of mills but as I found out some very important information was left out such as how one inserted the wrought iron grudgeons into the ends of wooden shafts using hot lead in such a way that the forces directed on them due to operational requirements did not lead to failure
What I did find out over the years was how smart these old millwrights were and why the working examples survived for hundreds of years!.
Examining early examples of barns in particular one thing that stood out was that the old mills in our area could handle and process logs up to twenty feet in length That had an impact on our mill at upper Canada village because it mistakingly had been restored to only cut and process sixteen foot logs
One thing that landed in my plate a number of years ago was to refit the mill with a saw frame that could handle logs of a twenty foot length
One thing that led us in this direction was the vertical sawn planking in many of the local barn floors, and the census of that time pinpointed the local mills in operation that used water power as their driving force, and were vertical blade mills
Well it eventually came to be and we began to faithfully process twenty foot logs
I will tell you one thing logs large enough to process four inch by twelve inch by twenty foot planks in length are heavy indeed and made the saw frame groan under their weight
Well I have to go
Richard The northern hewer
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Re: historic hewing questionnaire
[Re: northern hewer]
#34279
11/14/17 02:25 AM
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Posts: 1,193
northern hewer
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Hello everyone tonight
I do believe that we have pretty well covered the working apparatus of the mill from the bottom to the level of the saw frame, but I am sure that some small items have not been covered
One might ask just how much water power is required to drive the mill, well as far as we can asertaIn running at full speed which is one hundred and twenty five Rpm a it requires an eight foot head of water and will consume approx twenty two hundred gallons per minute
Getting back to the saw frame and how it functions, well each down stroke of the blade will advance the frame with the log attached approx three eights of an inch, and the top of the blade being slightly ahead and out of the perpendicular. By one half inch allows the log to advance three eights of an inch on the up stoke without scraping the points of the teeth or trying to lift the log.
The up stroke also clears the saw dust still embedded In the cut. On a large log the cut can be in excess of the travel of the blade which is eighteen inches. Nine inches down and nine inches up which gives a total of eighteen inches, cuts can sometimes be twenty four inches in large logs which means that in the centre of the cut clearing the sawdust is a problem so a very slow speed is required to allow the. Sawdust to clear, this brings us to how the Miller can adjust the forward speed of the cut, another topic!,
We'll have to go Hope to hear from someone who might like to pose a question or say hello
Nh Richard casselman
Last edited by northern hewer; 11/14/17 02:28 AM.
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Re: historic hewing questionnaire
[Re: northern hewer]
#34280
11/14/17 03:31 AM
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Dave Shepard
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Hi Richard. Thanks for adding more to the story.
We're hewing new rafters at work and debating the use of the adze in historic hewing. We find no evidence of the adze in our area, but the popular misconception persists.
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Re: historic hewing questionnaire
[Re: northern hewer]
#34281
11/14/17 01:26 PM
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D Wagstaff
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Oh, I am with Shepard 100% on this. Never have I seen conclusive evidence, just the fog of conjecture. Some old French timbers fall into the category of raising the possible use of an adz for surfacing, still, I cannot say I am much convinced.
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Re: historic hewing questionnaire
[Re: northern hewer]
#34282
11/16/17 02:59 AM
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Posts: 1,193
northern hewer
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Hello everyone tonight
Thanks for coming on board and introducing the adding question or should I say dilemma
Well I personally never used the adze during the hewing proces, even on small rafters which have a tendency to bounce around and need special support, the adze of course would have been used to shape the cog on the lower end and the half lap on the top, shaping the one lone flat side or the complete tapered squaring on some special rafters was a broadaxe only job and would have been much faster for sure
When you stop to think about it using a scoring axe was by far better and easier to accompany the broadaxe ing process simply because of the necessary change of position to a commodities that tool its shape and handle configuration
AdzIng for sure was used to dress and smooth the hewn surfaces in some instances
Well got to go
Richard No
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Re: historic hewing questionnaire
[Re: northern hewer]
#34289
11/28/17 06:18 PM
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Joined: Feb 2006
Posts: 718
Dave Shepard
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Boatbuilding?
My argument isn't that an adze was never used on a timber. It is that the typical hewn finish in my part of the country was done only with a broad axe. The misconception is so widespread that people automatically mention adzing whenever you talk about hewn timbers, or hewing.
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Re: historic hewing questionnaire
[Re: northern hewer]
#34290
11/28/17 07:16 PM
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Joined: Feb 2012
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D Wagstaff
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This picture is of a millwright, fits nicely with the story from Richard, I was today looking through a folder of old Xeroxed material that was handed to me and found this picture at the back. I agree with you, just because the adze may have been used in some circumstances it does not follow that it was used in other circumstances. Adze use for straight timber work makes no sense to me.
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