2. Find Information

Where to find information for the species you will be drying.

Since 1920, Universities in Europe and the United States have been making suggested drying schedules on different species and thicknesses. There are three general types of drying schedules available:

North American:

Is based on constant fan operation and Wet/Dry bulb temperatures. These can easily be converted into a Temp/RH% schedule for those kiln controllers which use an RH sensor instead of a wet bulb.
These schedules have numbers like T4-E6, T2-C1, etc.

British:

These schedules are also based on a Wet/Dry bulb temperatures and can be used the same way as North American schedules.

Drying gradient:

The species are normally divided into 4 groups depending on the drying characteristic. Each group and thickness is then given a maximum drying gradient that one can use and still expect a high quality drying.
The temperature will depend on the specie you are drying. Generally the slower and harder the specie dries, the lower the initial temperature is.

Caution:

During the last couple of decades the average kiln drying temperature has been gradually lowered in order to increase quality. So if you are looking on an older drying schedules to help you make a new drying program/schedule you should be aware that you probably need to reduce the temperature significantly.

There is much good literature available on drying lumber; but you can also find some which is less clear and sometimes has questionable accuracy. When you are studying the subject always use your common sense and try to compare it to your own experience.

We hope this information meets with your expectation and approval. We always welcome your opinions and suggestions. Feel free to email us at techsupport@kiln-direct.com.