Archive for March, 2008

Mar 31 2008

Understanding Fractions, The Key to High Accuracy When Measuring.

Published by under Metrology,Skill Development

I want to have that little talk with you about, Fractions. Yeah. But the plan is, if all goes well, that it won’t hurt – as much as it did last time. Working in sub inch territory usually involves the use of little buggers. The problem many people have when working with fractions, is that they relate the use of the common fraction to their math education experience when they were in school as children.

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Our school systems scared the bejeezus out of everyone by forcing us all to learn a series of mathematical exercises, which evolved around fractions that we would never use again in our entire lifetimes. For many, this often created mental blocks to the entire notion of fractions, even the simple useful ones, because after that harrowing experience, it seemed that nothing pleasant could possibly come from the manipulation of fractions at all. In fact, when people are faced with dealing with fractions, they generally feel some panic along with it. A panic that rates up there with the sound of high speed dental drills and root canals, and it is most likely from their harrowing experience in math class. Folks remember what all the wonky practice of solving mismatched fractions was really like, and relate that it was way, way too similar, and maybe even the diabolical preparation, for diagramming English sentences later on during their high school education.

I hope I can help make this a lot more user friendly! Continue Reading »

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Mar 24 2008

John Barleycorn Must Die. The History of Measurement.

Published by under Metrology,Thoughts and Banter

The way measurement is handled in the United States, and to some degree the UK and Canada, depending on the person’s age, is the foot. The foot has an interesting history, and there are a couple different accounts you can go with, but it has its beginnings in the Roman Empire.

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Before the world was very big and there was not so much need to measure great distances, measurements were based on what a man had, er, handy! Sure there was mans foot, which is the foot’s namesake, but it didn’t keep a consistent length, so three hands, four palms and twelve thumbs worked better to more consistently derive it. So the Foot became the distance of 12 thumbs, and the width of the thumb became the inch. Welcome to base 12 measurement. Continue Reading »

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Mar 23 2008

Using Cross Dowels for Knockdown Joinery

The big thing about using steel cross dowels for knock down construction is that your layout must be absolutely meticulous. I have, and continue to use these a lot in jig construction, but there are a lot of other great applications. cross_dowels.jpg

While a lot can be done with these, a common application is for use in workbench base construction. Real life happens. People move, circumstances change. Sometimes the dream shop in the basement relocates to a garage or an outbuilding. Many of us cannot build a bench with the certainty of knowing it will never need to be easily transported to elsewhere at some future point. This makes the use of steel or brass cross dowels a wonderful option. Continue Reading »

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Mar 18 2008

Metrology, The study of accurate measurement.

Published by under Design,Metrology,Skill Development

Metrology is defined as the science of measurement. More particularly for the woodworker or the home shop machinist/toolmaker, one of the divisions of metrology, which is of particular interest, is applied or industrial metrology. This is about the application of measurement, the suitability of measuring instruments, their calibration, and the quality of the measurements they produce.

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So the accurate instrument is applied to create a needed measurement. The quality of the measurements becomes the layout that evolves into successful production. The gist of it is that the woodworker is trying to produce a thing, and the thing is often rendered from a drawing and plans which include materials and cut list. The go between that takes the project off the prints and puts it on the materials being used are the tools of metrology. The measurement and layout tools. Continue Reading »

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Mar 15 2008

For Layout and Marking, Chalk is cheap!

Layout work is a tedious and exacting part of woodworking. We select boards for size and grain orientation. We hope this is in part, the “art” of our work that separates our project from that which is good, to that of greatness.

We sharpen our tools and skills, we buy accurate measuring and marking tools all with the hope of accurately conveying our vision. We go to work and accurately lay out the work, checking, and double-checking everything as we go to assure we have everything right. Continue Reading »

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Mar 10 2008

Tooling up with Hand Tools? The Big List.

Back in early February 2008, an interesting thread was started on Woodnet.net. Bob Feeser, rfeeser to those who may look for his writings, was asked by a friend to ”provide a list of what tools a well-equipped small, machine-free shop might have”. So he consulted some texts he had on hand and “enhanced” it.

Turned out, the list is quite good. On Internet forums, one good turn deserves another, and so the feedback began. …And the list grew. People came up with some great additions for the list. Continue Reading »

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