Recently after posting on Facebook an image of myself carving a fairly good size panel in Mexico. A friend of mine responded by asked me if I had "flip flopped the panels".
What he was referring to was how the panels were glued together. Which was a good question since this was being used outside. In which case every other piece of wood in the panel needs to have its grain direction alternating. So if you look at the end view of a piece of wood you will see that the grain is circular and on some pieces it may look like a semi circle. Because if I were to have glued these panels with the grain all going in the same way, eventually it may very well look something like this...
By alternating the grain you can greatly reduce this sort of warping problem. So if you want you project to remain looking like the illustration below, then you need to alternate the direction of the grain.
Aa a good rule of thumb, I prefer to construct all my exterior panels from pieces that are between 6 and 8 inches wide to prevent excessive warping. So if you have a nice wide piece of wood, save it for an interior carving. The reason I am suggesting using these narrow pieces is because if you go greater then 8 inches you surely risk having your wood warp. All wooden panels have the tendency to warp. Its our job to minimize this as much as possible. If you are planning of carving a large slab and you want to keep it from warping as much as possible then I recommend hat your slab be about four inches thick.
By alternating the grain pattern of every other board you are helping to prevent the panel from warping into a circle. If you have made tables or other interior items you most likely have tried to match the grain as best as possible to make your item more pleasing to the viewer. Meaning that all the boards would have the grain running in the same direction. However, when you are making panel which will be exposed to the outside elements such as a door, a wall panel, or a sign you want the grain of each piece of wood to be going in the opposite direction. I do this with every carving panel I glue up no matter if it is used inside or outside because I never want there to be any possibility of the panel warping sometime down the road when the customer decides that they want to hang it outside.
Another thing to take into consideration when you are doing a carving whether it is to be for interior or exterior, is to have the grain running along the length of the boards to be going in the same direction.
This means as you see the grain on the side of the board, you want all your boards to have there grain diving in the same direction and not opposing each other. Look at the below illustration you can see the grain on the left two boards are running in opposing directions, where as the grain on the right two boards are running in the same direction.
By carefully studying your pieces of wood before gluing it together you will make your time carving much more enjoyable.
Terry R. Wolff, Woodcarver
Sharing over 37 years of experience as a professional woodcarver.
You can always email me with your comments, questions, and suggestions.