I have a hard time remembering some of these old woodworking formulas and shop math tricks. Truth is, I don't need most of them that often, and as I'm getting a little older with each passing day, I tend to forget them. So, I put them here in the hope that I'll know where they are when I need them. If they help someone else, so much the better.
This is thrown together in a random and somewhat hodge-podge manner, but there are links to get to the major areas. Or, you can just browse around. And there are resource links at the bottom.
|
Marking & Measuring » |
Future Use » |
Miscellaneous » |
Many consider our craft an art form, but I rather prefer Sam Maloof's take on the subject... "I'm just a woodworker." At the same time, it seems I can never remember the "standard" dimensions for "standard" pieces of furniture over their artistic variants. Luckily, the fine folks at Highland Woodworking have tried and true dimensions all documented for us. The web page is here and there is a corrosponding .pdf. Make sure you tell them "thanks."
Here's another "Old Timer's Trick" to divide the width of a board into equal
and even sections, say for example, laying out dovetail pins. Slant a
ruler across the board so that the ends are on even numbers. Then you
simply mark your points.
For example, in the photo, the ruler is laid out so that zero is on one corner and four is on the other. I marked my lines at 1", 2" and 3". Those marks are all equidistant from each other. I marked off my pins from those marks, then just eyeballed what was left to make the half pins on the end.
I've seen these things expressed as degrees, grade, and slope. Old timers called a "rise to run" which was basically measuring one inch over and some number of inches up. One then set a sliding bevel to those two points for layout. It's still a great method. See the photo...
| Rise to Run | Degrees | Grade |
| 1:1 | 45.0° | 100% |
| 1:2 | 22.5° | 50% |
| 1:3 | 18.4° | 33.3% |
| 1:4 | 14.0° | 25% |
| 1:5 | 11.3° | 20% |
| 1:6 | 9.5° | 16.7% |
| 1:7 | 8.1° | 14.3% |
| 1:8 | 7.1° | 12.5% |
| 1:9 | 6.3° | 11.1% |
| 1:10 | 5.7° | 10% |
For a very quick geometry overview, refer to the The Slope of a Road or the "Pitch" of a Roof web page. If all you need is a quick reminder, check the table above. Decimals are accurate to one place.
|
Lots of us are relegating an old PC or laptop to a corner of the shop. It only stands to reason as things like CAD, cutlist, estimation, and other software packages make it into the shop. It's convenient to have a PC where the action is. It's also a great way to check out our favorite woodworking podcast in the comfort of our shop!!! At the same time, it seems I can never remember the conversion or fudge factor for something as I'm out there with the measuring tool of the moment. That's where this little utility comes in handy. It's called Convert and I've been using it for years. It's the handiest little program, and it will change virtually any unit of measure to another. It's never failed me, and it's absolutely free. You can get it at http://joshmadison.com/software/convert-for-windows/. I've always used Windows, so you'll have to check their site for Mac and Unix varients if that's what you need. |
Brady, Kevin. "Basic Math Formulas for Woodworkers". 2010.
<http://www.kevinsbrady.net/wwmath.html>.
(24 Feb. 2010).
"Helpful Woodworking Formulas & References". Highland Woodworking. 2010.
<http://highlandwoodworking.com/library/shopmath/shopmath.html>.
(24 Feb. 2010).
"The Slope of a Road: or the "Pitch" of a Roof." and linked articles. Gradient, Slope, Grade, Pitch, Rise Over Run Ratio. 2000.
<http://www.1728.com/gradient.htm>.
(24 Feb. 2010).
"Woodworking Math Tables, Formulas and Calculators". Rockler Woodworking. 2010.
<http://www.rockler.com/articles/display_article.cfm?story_id=97>.
(24 Feb. 2010).
Also see:
WoodshopTeachers.org