Kiln Drying Forum

Wood Drying Topics => Stacking/Sorting Wood => Topic started by: hotwoods on May 17, 2012, 08:34:31 AM

Title: Mixing thicknesses
Post by: hotwoods on May 17, 2012, 08:34:31 AM
Has anyone had any experience mixing thicknesses?  I am specifically interested in mixing 10/4 with 12/4 or 10/4 with 8/4.  The species is red maple.  I am also wondering about mixing species such as hard maple and yellow birch.  Also I think red maple and white birch may dry well together.  We will also be drying Ipe.  All of this drying is being done in order to get the wood to at least 8% (preferably lower).  Once the wood is dried it will be thermally modified.  Our website is www.hot-woods.com for those who are interested in our process.
Thanks for any help on this.  The reason I need to blend thicknesses is that I am working with figured maple and its expensive to get a whole load of one thickness together.
Title: Re: Mixing thicknesses
Post by: MichaelM on June 01, 2012, 08:27:46 AM
I suppose it has been two weeks and no one has answered this because it is not done much.  If you do mix, you need to dry for the thickest, most defect-prone wood, then start equalizing based on the fastest-to-dry wood.  It's not an economical way to run a kiln.  You mention that the wood is expensive - this is even more reason to not mix types.

Another factor to consider is that it will be difficult to load and baffle a kiln with many types of wood in it.  The packs are usually different heights and they don't stack well.

So, people do mix types of wood.  It's a matter of making your best guess from past experience about what will work together and where to put it in the kiln for best results.
Title: Re: Mixing thicknesses
Post by: kilnguy on July 10, 2012, 10:18:19 AM
depending on the specie I will mix certain thicknesses like 4/4 and 5/4 ash or 7/4 and 8/4.  As a rule of thumb I won't mix thicknesses greater than that (such as 6/4 and 10/4).  I also control based on the thickest lumber in the kiln, but I will sample the other varying thicknesses to be sure I know what's happening to them.