I would like to raise the topic of the carpenter as a tool and template maker.

I have from time to time examined and worked on square rule pre-civil war barns. One common feature of the frames is the absence of tick marks or length measurement on the timbers. The markings of cut lines and gains are cut directly into the timber without alignment marks. The current layout practice taught at guild workshops requires numerous measured lengths and gains marked in pencil, first as ticks then as cut lines. Layout is then checked and knifed. The steel tape, framing square and chalk line are the major regulating tools of layout, and numerical measurement and referencing the guiding concept. The early to mid19th century carpenter certainly did not have a steel tape and the framing square was very likely hand-made wrought iron of non-uniform size. Measuring was accomplished thru a step and tally method using a reference rule to set dividers or trammels. The difficulty, individually measuring timbers for layout, presents many cost and control problems, especially in a step and tally system. So I have been puzzling thru the problems of a story-pole layout method as a solution to the historical problem and as a more efficient modern solution.

So if I had an 1820 tool kit and crew, I would propose that after the delivery of timber and lumber, the lead would be preparing needed layout tools, such as, story-pole stock, measuring rods, levels, plumb rules, straight edges, scratch gauges and squares. Meanwhile, the crew began the cull, grading, earmarking and correction. Layout would begin on the story-pole with the careful stepping of reference lengths. Since stepping must be to a line, a scratch gauge would be used to create a line that a trammel point could nestle into. Any sensible unit can be stepped 1, 2 or 3 feet, depending on the trammels beam, with odd inches added at the end. A good cross check method is a 12 step method, where a one twelfth scale length in inches and twelfths models feet and inches, for instance 14 and 5/12 in. stepped twelve times yields 14’ 5”. After primary references are scratched, gains and secondary references are marked. If you are laying out the plate line, each side of the story pole could represent a bay. The same referencing would apply to the sills and purlins. A single 14-foot pole could manage the referencing for a building over 50 ft. long. Again another pole to manage the bents and another for height. When needed, detailing can be laid on other poles but primary references could squared off the master template.

On to timber layout, the stock is on the horse, reference faces are verified with winding sticks and squares, and end length reference is squared around at one end. While story-pole is held by a helper along the arris aligned to the end reference, a carpenter would align a large try square to the layout and then strike out lines with an awl. The pole is moved to opposite side of the same face, aligned and lines are struck again. The timber is turned so the other reference side is up and the process repeated. A parallel and smooth pole can bridge undulations and wane and ease registration. Gains can be marked with a straight edge ripped to the dimension of the gain and registered to a reference face at primary length references or with a scratch gauge.

That is all for tonight.