So, I have finally got my first batch of beech plane blanks out of the kiln. I have dried steambent wood parts in my small light bulb kiln for chairmaking for quite some time now. That is a whole different process really than when drying wood blanks to make wooden plane bodies.
What is my aim when drying wood for plane blanks? Well, with a background in working greenwood I always have appreciated how wood works that has been air dried. It is just different. I don’t want to over rate it but the way the tools cut it is just different. As you can imagine I prefer it to the super dried stuff.
The difference lies in the fact that air dried wood never gets to a high temp like typical kiln dried wood. In the kiln the temp will generally get to the 160˚ range for many woods and some are higher. This is often done just to be safe and kill bugs or to set pitch in resinous woods like pine and to get the wood dried to a very low moisture content. However, it isn’t actually necessary to heat wood this hot to dry it.
It is important to appreciate that commercial kiln operators are concerned with speed since this affects profits. Not knocking this, they are businesses, after all. However, the resulting product is not as good as it could be for the artisan woodworker. I have been completely sickened at times to have bought a wood like white oak that was beautiful wide boards and paid premium prices to only find that 30-40% was a waste because of drying defects hidden within the wood.
Anyway, these sorts of things, among the fact that I couldn’t find certain wood cut and dried in the orientation or sizes that I wanted, lead me into the kiln drying business. …for myself of course.
So I started researching this about a year ago and decided to go with a low temp dehumidification kiln. It basically allows me to control the environment in a closed chamber. Imagine wood drying on a perfect summer day at the optimal range of temperature and humidity for that wood. Now recreate that day over and over until that wood is dry. That is what this kind of kiln allows me to do. The blanks I am drying never get over 105˚ or below an average moisture content (MC) of 10 percent.
Yes this can take longer than a high temp (HT) commercial kiln but not very much longer. For most hardwoods it can be dried just as fast. In fact since I am not super drying the wood to, say, 6-8% MC (because these will be used in a open shop environment) then I don’t have to dry as long. An advantage is that a low temp dehumidification kiln uses way less power than conventional kilns. Mine can run 100% of the time for 30 days for around $53. Of course, high tech kilns like this are not cheap to begin with. Think hybrid electric cars, you pay up front to get low operating cost.
I think this is the best of both worlds. After all there are drawbacks to air drying lumber. Air drying can take several years, first off. It is also subject to a lot of drying defects in actuality since you can’t control the weather, as we all know. Surface checks are very common in air dried wood and then there are woods that are very susceptible to stain from mold and fungus if not dried quickly enough or cut in the “wrong” season. Beech is one of the worst for both surface checks and fungus stain when air dried.
Here are a few pictures from the process. I wish I had some of the log getting cut up a Curtis’ place. Thanks again Curtis for letting me use your yard!