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Scribe rule Timber framing book

Started by nicdonati, May 31, 2009, 08:05:54 AM

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nicdonati

Hi Guys,

I took a course a few years ago in square rule timber framing and since then have participated in several builds using saw milled square timbers. I fell comfortable and competent in this technique. I would like to learn a little more about building a frame with non-dimensional round (un milled) timber. Can anyone reccommend a book that deals with this (but not a book on log cabins!!) i just want to build the frame with round timbers and wattle and daub the walls. Any suggestions much appreciated.

Jim_Rogers

Welcome Nic......

I don't know if one right now, I'll have to think on it a bit and do some research about it and see if I can find one, and ask around.

When I find the name of one, I'll post it. But there is a good chance that there isn't one, as I've never heard of one, but I was told recently that I need to "get out of the sawmill more often".... ;D

Jim Rogers
Whatever you do, have fun doing it!
Woodmizer 1994 LT30HDG24 with 6' Bed Extension

nicdonati

That would be great and much appreciated!!!

bigshow

Robert Chambers' log construction manual has a chapter on it (timber trusses chapter).  You have to read closely to follow along with how he does it - good book though.  Best info i've ever seen on intro to roof geometry.

B Allan Mackie had went to primarily round log timberframe construction for awhile.....but looks like that has morphed into CNC timberframing (www.daizen.com)




I never try anything, I just do it.

Stumpkin

There seems to be very little information on scribe rule layout in print.

Best I can find is here -http://archtimberframe.com/?q=frenchscribe
"Do we know what we're doing and why?"
"No"
"Do we care?"
"We'll work it all out as we go along. Let our practice form our doctrine, thus assuring precise theoretical coherence."      Ed Abbey

Mad Professor

I do not believe early scribe rule in this country had layouts on perfectly flat floors upon which to trace things out, how did they do it????

Practice makes perfect.  Get a chalk line, plumb bob, divider/compass and study how to make angles with the above rudimentary tools on Marc's site.  Everything including mortices/knee braces/squaring/irregulars can be done, ......perfectly.

Base your basic layout on a master set of circles from your divider.  Scribe them as the master builder did onto a beam for reference.  Set your divider from that for each piece.

What I have learned from "rough beams" is that the ends were laid out first, e.g. hewing from a timber/log. Those circles became the edges of the beams







Jim_Rogers

It's my understanding that there are many ways to "scribe" a frame. The French method shown in the above link is only one way of doing it.
I'm sure that the early American settlers didn't have a nice finished floor to draw on.

The timbers were most likely "laid up" on blocks out in the yard and then scribed to each other.

I believe the mortises were cut first and then the tenons were cut to fit the mortises.

Jack Sobon wrote several articles for the Timber Framing magazine about how he did his side entry English style barn, a few years ago. And I visited him there one day while he was working on his barn timbers:





As you can see in the above photos, he was working on his frame right there where it would be raised, over some rough foundation stones.

He used the metal pegs to pull joints together for further scribing.

We hope to be able to offer these "metal drift pegs" for test fitting your frame joints in the near future for sale.

Jim Rogers
Whatever you do, have fun doing it!
Woodmizer 1994 LT30HDG24 with 6' Bed Extension

Dave Shepard

I made a couple of pins today. A curly ring on the top like those I made before takes a lot of time, so I bent the ends over like some that I have seen before. Saves a bunch of time. I asked Jack how many he had a couple of months ago, he said 30 some. I asked how many he had used at once, he said "All of them". :D This style can be tapped out with a hammer, or if you put a block of wood on top of the timber, you can use a wrecking bar to pry them out. They are 16" overall length, 3/4" diameter. I am going to experiment with making a simple turned ring, but I've got to make a jig first.

Wood-Mizer LT40HDD51-WR Wireless, Kubota L48, Honda Rincon 650, TJ208 G-S, and a 60"LogRite!

Brad_bb

This last week I was at a TF course where we used square rule, but the instructor also did a scribe rule layout demonstration.  His demonstration was for scribing irregular timbers like crotches or timbers sawn on two opposing faces only, into a rough sawn timber bent.  The irregular timber was adzed where it was to have tennons to get those ends approximately square (and I mean only approximately by eye).  The timbers that these were to be let into were leveled on blocks.  The area of the timber where the bubble level was placed was lightly planed to assure a smooth flat surface and this location was marked as level.  The irregular timber was laid on top and it was leveled in the middle in a similar way and wedges used on the ends to keep it level.  At this point the ends were not perfectly square or level to the timber they rested on.  A plumb line was dropped from the irregular timber so that the string was barely not touching the timber that would be mortised.  A compass was then used to transfer where the corners of the irregular timber down to the mating timber, offsetting from the plumb line the same distance measured on the irregular timber.  This is certainly easier to show than to describe.  It all makes perfect sense when you see it done.  Consider going to a TF guild event where it will be demonstrated.  I think I'm going to the KY rendezvous July 2-4.  It's the cheapest guild event there will be.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

gdpipkorn

Thank you for your post. I am just beginning my build from timbers milled a year ago. They got all split and twisted so I needed this info to confirm what I took 3 weeks to figure out.

Heartwood

The book Timber Framing Fundamentals has a three-part series of articles on Scribing techniques, including bubble scribing and plumb line scribing joinery in round and square material. It's available from the Timber Framers Guild.

Don P

I've been watching this video on plumb line scribing this evening;
https://www.youtube.com/watch?v=Vtp0S-MseJM

Neil Martin

Hi there - I've been looking at this amazing forum for a long time now, and as i've seen this thread thought it was a good time to introduce myself. 

I'm a Uk based, fairly new Oak framer. And I did a course a few years back learning historical timber framing techniques. I found it such an amazing and rewarding thing to do i've now quit my last job and have started up a small business growing and learning as I go.  

Your right - information on those historical techniques (At least where they aren't french) is incredibly hard to find. Detail around scribe rule joinery and method seems mostly limited to sketches without dimensions, and description usually in the context of a complete building rather than a forensic look into the many eventualities that scribe rule can throw at you. 

The course I did, was an introduction. But a great one. it introduced me to the way of thinking that is required to figure out how to make any joint, but most certainly does not shortcut you to being a great 'cutter' of joints. 

a flat floor helps for sure, but is most certainly not necessary. - I'm currently framing out in the woods with about 1m slope over the length of my ever changing framing bed. 
Some of the methods and tools date right back to the Egyptians. 

But as i try to learn more and more, i have found myself either learning more of a modern style of scribe rule, and also mixing it up with square rule technique in areas. 
But the real pull of historical scribe rule is how they did everything without really needing to measure anything. 
There are so many tricks you can do with a pair of dividers that can get you any geometry you need. And i'm always thinking to myself when trying to figure something out on my own that carpenters of the past almost certainly had a far easier way to do this. - and i've usually been proved right in the end.

Just really briefly (as i really should be in bed right now) i'll mention a couple of the key features that I learnt on the course that I still use all the time. 

Datums
your datums in scribe rule (at least how I have learnt it) are always the corners of your building, or bays. 
If its a 3m x 3m bay for example your datums will be a point on the aris between the outside and  top face of the beam , or fair and outside face of a post. 

The Plumb mark - this is where you choose your 2 reference faces. - You orient the timber your working on (in most cases) so that the spring / bend in the timber is facing up and out so far as it's position in the building would be. 
You then choose a point away from any intended joinery to make your plumb mark. - pair down the outside face until there is no rocking under a straight edge and then create a perfect right angle by using your framing square to guage how much to remove from the top face until you have basically made a very small section of your beam, 'true' 
in reality it's only the 3 corners that matter, as long as they are square to each other. - you can have a dip between them, and that is actually preferable as after a while your nice flat surfaces can crown again. 

So that is now your way of plumbing and squaring that beam forever more - analogous to the lines you draw on the ends of the timbers in square rule. you use it to align your beam in your layouts and when assembling the building. 

Method 1 - Double kerf technique. 
This is where you do a basic layout - take a 3m square sole plate for example. 
-You'll measure your 3m on the beams with the mortices, and the beams with the tenons. 
-with dividers you will take the width of the beam with the mortice (at the exact corner that the mortice will line up to the tenon) and then transfer that measurment to the tenon beam, and subtract that off the 3m mark. to make your final shoulder position mark for that tenon.
- then the good bit - you add a small amount back - a fingers width or so back towards the end of the beam and make a mark. and also mark out from there the length of your tenon. 

- Now mortices marked and tenons mark cut the joints, but only cut the tenon shoulder back to the 'fake' line that you marked for the shoulder. 

- you then partially assemble the complete sole plate, the above process having been done on all for corners. you dont tightly fit the tenon to the mortice at this stage, you just make sure the distances they are apart match up for both left and right sides of the building. 
 make sure all beams are plumb level and square. - and then set your compases or dividers to the width from the face of the morticed beam, to the 'actual' tenon shoulder line. and scribe the whole way round. 
you've now transfered that face of the mortice beam to the shoulder of the tenon. and you can now cut and fit that just as you would in square rule. 

As you draw bore with the peg, you do this lightly at first. kerfing the joint with a saw to further face match the joint. 

- As my tutor suggested. - this method is slow and is probably the cause of scribe rule going out of fashion. it requires you to basically lay the frame out 3 or 4 times before its all fit together as it should. 

Method 2 - i wont go into detail here, but this seems to be the preferred method and the one I now use for the sake of speed, but not necessarily an improvement.

Hanging a plumb bob over the shoulder lines of stacked timbers and transferring the distances to map one face on to another. ( i will go into more detail if someone would like) 

This can be done with or without a full scale drawing on the floor - it really depends on the size and complexity of the project. 

the building i'm doing at the moment Ive just taken 5 key points and drawn those onto sheets of ply which if screwed into concrete blocks (I cant afford a workshop yet) 
i then lay those blocks out and get them set up perfectly and they dont move for the rest of the project. i can then line up the 4 corners and ridge of a bent, and everything else can be taken off measurment lines on the timbers, and scribed by stacking etc. 
so sling braces, or normal braces, collars, any secondary timbers can basically just be scribed after the initall fit of the primary timbers, which were set out over a sort of drawing. 

Really sorry for the rushed descriptions, but thought i better finally post on here. Would love to hear from any and all about anything scribe rule. it really is a bit of a black hole in terms of actual detail.














Brad_bb

Funny you posted that video Don P.  I've been watching that one a few dozen times in the last couple years.  It's also a natural ASMR video and will totally relax you.  After watching it so many times, I've been able to pick up bits an pieces to start to understand him.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

Chilterns

A recent book published jointly in the UK and USA is :-

SOMERVILLE, R. J., 2021. Barn Club. Vt, USA  & London, UK. : Chelsea Green Publishing.

ISBN 978-1-60358-966-6 $25 / £20.

This book covers laying out frames including plumb-bob scribing together with accompanying pen and ink sketches. This book was reviewed by Jack sobon.

Chilterns
p.s. Neil where are you based in the UK

Neil Martin

Quote from: Chilterns on June 30, 2021, 04:47:50 AM
A recent book published jointly in the UK and USA is :-

SOMERVILLE, R. J., 2021. Barn Club. Vt, USA  & London, UK. : Chelsea Green Publishing.

ISBN 978-1-60358-966-6 $25 / £20.

This book covers laying out frames including plumb-bob scribing together with accompanying pen and ink sketches. This book was reviewed by Jack sobon.

Chilterns
p.s. Neil where are you based in the UK
Hi Chilterns, - I'm based in the south east. Gatwick / reigate area. 


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