FAQ's

Question: We are a furniture manufacturer in Mainland China. We use wood from South East Asia and sometimes export our furniture to Europe and North America. The wood furniture we export usually shrinks and Cracks. Do you have solutions for us to solve this problem. I know I can have the wood kiln dried but that is very difficult to accomplish. Besides this method, would your company suggest other solutions for us?

Mainland China

Answer: Your question regarding problems with your wood product shrinking and cracking when exported to locations with less humidity is one that has plagued woodworkers the world over. All wood shrinks and swells with changes in moisture content. Some species of wood change less than others and it would be important to find woods which have minimal movement to use for production and shipment to a less humid climate. Another precaution is to test the moisture content of the wood being used in production. In a humid, tropical environment the wood should stabilize at a residual moisture content of 12% or less. If the moisture content is higher, the wood should be air dried until the moisture content reaches stability. Expect that in a temperate climate such as Europe or North America that the residual moisture in wood will stabilize at 8% or less. Once you have determined that you are using the best wood species possible and you know that you are using the driest wood possible in your climate, the rest of the solution will have to do with the furniture design and wood selection. It is important to allow the wood to shrink naturally without being restricted from the movement you know it will make when its moisture content is reduced. For instance, let panels float freely inside of dadoes rather than gluing the panel in its dado. Seal all the end grain so that the wood won't dry and shrink more quickly on the ends. That will reduce cracking or checking due to non uniform shrinkage. Wood does not shrink evenly on each of its axes. It shrinks the least in length so avoid gluing wood together in opposite grain directions. Wood also shrinks less when cut in a quarter sawn manner, exposing a vertical grain surface rather than a flat grain broad surface. By using quarter sawn lumber, you may reduce your shrinkage factor by 60%. If you need more help designing furniture for shrinkage, let me know. I would be glad to examine your furniture designs to look for ways to alleviate your problems.

Good luck, Bill Lutes