Monday, February 27, 2017
How much does your wood move?
Wood movement is one aspect in furniture making that is more important than many really know or willing to understand. There are books, articles, and charts to determine wood movement and one particular book that comes to mind is Understanding Wood by Bruce Hadley. While books and charts are good sometimes recording wood movement physically is a better option. Especially since most lumber that are available these days are not fully mature before they were cut. Also sadly the wood drying has changed rapidly. Today wood is being pushed to the limits, often drying too quickly. I know this from the visual piles of wood in the short bins full of end checks that go several feet in from the ends.
My preferred method to measuring wood movement is to gather several pieces of soft wood and hard wood that I commonly use. For me that is pine, poplar, cherry, oak, walnut, maple, and mahogany. I often use a small off cut that has been milled over the years. I will use this off cut record how much the wood itself has or will move in width. Several times a year I even measure the length. Yes even wood moves in length, but not much. When recording the width I also record the date, humidity, and time. A perfect example it the pine shown in the photograph, it has moved a 1/16 of an inch just this month alone. The humidity has changed rapidly last few weeks and that plays a huge role in furniture making. I will record all wood movement for 1-2 years to ensure I get an average and understanding of possible movement. The instrument I use to measure humidity and temperature is the AcuRite 00613 Indoor Humidity Monitor. I have one in every room in my shoppe and it is quite accurate.
So while its fun just slapping furniture together, always beware wood will always move and if you don't compensate for wood movement the results can scare you. Trust me!