brad,

Do you have either of Jack Sobon's books. Both of those present square rule layout from the edge very well.

The square rule originally used chalk lines because it was originally used on hewn timber. the edges of hewn timber have lots of dips and swells, as well as fat spots and out of square areas. All of which make applying a square to themis too irregular to accurately place a square on.

As sawn timber became more accurate, the need for reference lines went away. If the timber is straight and regular, why snap a straight line? It's a wasted step if the edge is true. For a lot of sawn stock, this is the case. The edges were pretty straight, but the dimensions varied enough to warrant reductions and gains at the joints.

The reason this topic is talking about snap lines so much is because the original poster was asking about how to deal with extreme situations.

Understood. So if the face of the timber varies by say 1/16th, or 1/8, or 1/4 inch along it's length, would you then need to revert to chalk lines? Would you have to asses each timber one by one by pulling a string or the chalk line along it to assess how planer it is in the areas where joinery will be cut? How much out of square would you accept(from primary to secondary reference face) before reverting to chalk lines?

I've seen lots of hewn barn timbers that have square rule layout and no chalklines, in fact I have rarely seen chalklines in barn construction around here. They must have used the square like a transit I spose, sighting down along the beam to find the edge.

Mark,

Could be. I like the idea of a transit.

Check out this description of square rule from a 19th century carpenter.

Light and Heavy Timber Framing Made Easy by Fred T Hodgson

When framing to lines, this is more or less the method we use.

By the way, I saved that entire book as a pdf, took it to a printer, and had it printed and spiral bound for about 35 bucks. It's public domain, so copyright laws don't apply. And it's a great read.

Here I go out on a limb. I am most sure square rule was developed for sawn material. It was part of the transion to speed up the framing process.

As for Mo's first post and his question of the downside of square rule, Gable is right, Mo example is a extreme one. 98% of my work is square rule all off an edge, no snap lines. Some times they are nice and square other times out of square by up to a 1/4". You use the aris, the true corner of the ideal timber. I hardly ever see twisted or bowed stock which is unusable. Most of my stock is soft wood and reasonablely fresh. If it was to sit around for ten years and it was hard wood I would have issues. The old frames were more likly to have been cut green and more true. I will spend some time looking at Gable's last post with the Light and Heavy...... link, it sounds interesting. Tim

It is interesting. The term "boxing" for square rule is a new term to me. I also liked the stepped square, sort of like the Big Al square, but with a bigger fence. And a way to reduce "blunders". And much more. Tim

Tim,

The earliest known square rule building is right around 1800. The transition really took off just after the War of 1812 and was fairly complete by 1825. In most places, that predates the widespread use of sawn timbers.

Maybe Will T. will chime in -- he has studied the "Great Transition".

That book looks cool. Where did you get the pdf, Gabel? Right off the site you linked to? CB.

Gable, since my first visit to this fourm I have learned much. I am still learning. Some of my comments may be a bit off that is for sure. In some ways I am just thinking aloud, with a base of common sense.

In the span of 25-50 years of the development of square rule, with the use of snap lines, things changed rapidly. That span of time is only half the life of a person, not long at all. Most people saw the changes and moved along with them and adding to them. I think this works in with the "Great Transition". I hear there is work in print on that, as well as the artical on snap line square rule coming our way via Timber Framing.

The town of Machias, where I grew up has a historical building cared for by the Daughters of the American Revolution. It is a dated building via specific records. It was built in 1770, the majority of the timber is sawn with a few hewn pieces. It is not square rule. The town was settled in 1763, when the French was driven out. The French settlement was not much, no development, more of just a presence. The saw mill was the first first priority. There was a huge presence of saw mills up and down the coast. Powered by rivers as well as the tide. lots of the mills were just temporary, and moved from tide pond to tide pond as the timber was cut and the land exposed. This is all within the dates we are talking about. So sawn stock was avaliable to aid in the development of square rule. In my limited literature I find no specific mention of only hewn timber, but I do see sawn and hewn used together, suggesting it was used on both and in the long run sawn timber became the predominant material allowing the snap lines to be lost as well.

Here is the odd thing. Most of the old farm buildings I see have a mix of sawn and hewn stock and almost all are scribed. The exception is the town buildings Hall and Churches, these are square ruled.

By the way, in the War of 1812, Machias and the surrounding area was taken over by the British, becoming British territory.

I would like to hear more on SLSR and it's history. Tim

Ok, so I have to own up to something today!! I went out to buy braided fishing line for my chalk line but didn't fully read the posts!! I bought 15 lb test!! Let's just say it dosen't work so well!! Line is so thin is comes out without chalk on it!! Whoops!! I guess I gotta go fishing now!!

Carlos