I bought some hard maple from a different source than I usually do. I paid extra to get White Hard Maple. After blanking a couple boards I noticed the new boards had brownish tan centers. What causes this? Do I have a reason to complain?

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It is a long story, but basically the wood was air dried, giving a white color to the shell. Then at 30% MC or a bit higher, the wood was put into the kiln and dried quickly and developed a brown color in the interior.

What should have been done differently?

Never mind, I found your 1998 article, "20 steps to drying hard white maple". I sure wish I could have discovered this before I bought the boards.

For those people without the article, the best approach for color is that if you are going to air dry, then air dry all the way to around 25% MC and then go into the kiln. The principle is that different drying rates give different colors and with heat, it is also darker. Also, when going into the kiln, never use an EMC higher than 12% EMC as that will be too slow and humid.

A vacuum kiln delivers pure white HM. Even SM comes out as white. I once saw a customer who had SM mixed with HM. The only way you could tell the difference was by looking at the ends.

Den is not correct. He should have said "a properly designed and properly run vacuum kiln...." The problem is that some kilns are poor and some kilns are not well run, so the color is not white.

It appears that vacuum kilns are used for small pieces of wood. I couldn't find 8 foot maple boards dried this way.

You are right, Gene. I should have said "our" kilns but I didn't want to boast.

And Bruce, we dry slabs up to 80" wide and 26' long.

Where can I see availability and prices for maple boards?

Bruce,

I see from your website you're in WI. I would have thought you could have found a lumber dealer with good white HM.

I will add this, although there could be some salesmanship to this statement from one of my lumber suppliers who does do a color sort on their HM, he does refer to a WI sort that is not as white as the HM they are drying that comes from northern MI.

I can also add to Den's claim in that I have a friend here in MI that has a vac kiln and is drying his own HM and is getting brilliant white out of it.

Best of luck,

Mark

2 of three "reputable" suppliers have sold me the tan centered white hard maple. My best supplier says white hard maple grading rules only cover the faces of the board, there is no rule that the interior of the board be white. So sap 2 face can still have tan interior. I am advised to cut the board's end off, to determine interior color, before I buy it. Good luck with that idea.