For the average woodworker, though, the sponge-like quality of woods is well known. When wood absorbs moisture, it expands. As it dries and the water is released, wood loses weight and shrinks. If you build something with wood that is not sufficiently dry, that shrinkage can ruin your piece, making assembled parts warp or joints fail.
That’s why, before working with any wood, you must know how to tell if the wood is dry enough. Here are a few tips:
Check the ends of the boards you’re planning to use. If they are cupped or warped, the boards are still drying and shrinking and are not ready to be used.
Take a board and lay it flat on your work surface. Using a sharpie, make a line across the board about an inch from the end. Wait a day or two and check to see if the line has moved. If it has, the wood is still drying and not ready to be used.
Check the weight of the wood. Heavier boards are typically drier than lighter ones.
-Look for cracks in the wood. While small cracks are normal, large ones can indicate that the wood is still drying and shrinking.
- 1 Drying Wood
- 2 How Dry Does Wood Need To Be?
- 3 What Is the Right Moisture Content of Wood for a Carpenter?
- 4 The Right Moisture Content of Wood for a Flooring Installer
- 5 How To Know If Your Wood Is Dry
- 6 Which Is Better – Pin-Type Or Pinless Moisture Meters?
- 7 Are Moisture Meters Accurate?
- 8 FAQs
- 8.1 Does coating wood with oil stabilize the moisture content in wood?
- 8.2 I use a lot of trimmed for for children toys, menu times I use rings of 1-3 inch in diameterI use pure tungFor these purposes I don’t care for wood shrinkage or wrapingTwo things are important for me – that wood will not crack, and that mold won’t developI’m looking for the % number that will be my upper boundary for oil applicationWould 12% be ok?Should it be less? 10?Ideally I’ll wait until reaching final drying but sometimes I need to use wood before that point
The drying process for wood takes time, with lumber stacked and separated so that all sides of the timbers are exposed. For every inch in thickness of timber, it takes 1 year for it to dry thoroughly enough to be worked. Time is money, as we all know, which is a significant investment.
A kiln is usually employed to speed up and simplify the drying process of green wood after it has been processed into usable board. The term “green rough cut lumber” refers to freshly cut trees that have not had time to dry, a phrase that implies moisture content. Green wood will be seen as having a 100% moisture level as opposed to air.
Several kinds of kilns may be used to dry wood. They are immense, insulated rooms with a controlled environment (humidity, temperature, and airflow) that speed up the drying process. The idea of kiln drying is straightforward: the higher temperature and airflow, under precise conditions that control the room’s humidity levels, equalize the moisture content in the wood more quickly.
There are different schools of though on how dry wood should be for woodworking projects. Some experts recommend allowing the wood to air dry first and then kiln drying it to the desired moisture content level. Others recommend using a kiln right away to avoid any issues with the wood warping or cracking.
Unfortunately, ineffective kiln management, such as an unsuitable pattern of controlled circumstances, can cause uneven drying. The outer shell may dry too quickly, causing the core of the wood to dry more slowly. When the core dries after being pulled between the core and shell, it can fracture and create a condition known as honeycombing. This is the result of the shell drying too quickly, which causes the inner core to be pulled out of position. Kiln-drying lumber is an industrialized process that requires expensive equipment and trained personnel. The stakes are high, as improper drying can cause extensive damage to wood.
How Dry Does Wood Need To Be?
If you’re an average DIY woodworker, it’s reasonable to assume that the wood you purchased at the lumber yard is dry enough to utilize right away in your shop. It has been kiln-dried under suitable conditions and poses no risk for your project.
So, you’re probably in the safe range of 6% to 8%, which is great news for almost any project, including cabinet making, furniture, toys for your kids, and even boat restoration. If the moisture level is too high, the wood would have to be kept for a longer time before being used.
Stacking the wood in single layers separated by scrap straps to expose all sides to the air, and running a dehumidifier in your business may be required. It will be ready for your project after it has dried up.
What Is the Right Moisture Content of Wood for a Carpenter?
Since wood warps and shrinks as it dries, woodworkers want it to shrink before they use it. If the wood shrinks after they use it, it will cause problems. You can minimize the expansion and shrinkage of wood after use by drying it to have a moisture content of around 8 percent. Use a moisture meter to check the wood’s moisture level before you use it.
Wood that has just been cut might have a moisture content of 40 to 200 percent, whereas the average level of moisture is 7 to 19 percent dependent on air humidity.
The optimum moisture content for woodworkers who make delicate furniture, cabinets, musical instruments, toys, plates, ornamental art, and other wood items is between 5 percent and 9 percent. However, this range may vary depending on the geographic region due to varying relative humidity levels.
The Right Moisture Content of Wood for a Flooring Installer
The National Wood Flooring Association (NWFA) provides installation guidelines for flooring installers. When determining the moisture levels that would be acceptable for wood flooring, a baseline for acclimation must be established by the flooring professional, according on the NWFA.
The wood flooring must be acclimated to the environment in which it will be installed. The term refers to the process of gradually adjusting the moisture content of the flooring to meet local requirements. The installer will need to calculate the correct moisture level for the wood by dividing the area’s high season equilibrium moisture content and low season equilibrium moisture content in order to set a baseline for acclimation.
If the expected equilibrium moisture content varies from 7% to 9%, the baseline wood moisture content would be 8%. The technician should inspect several boards for moisture and use the average of the results.
How To Know If Your Wood Is Dry
However, you may be wondering how long it will take your project to dry out if I don’t put any finish on it at all. Excellent question. Or perhaps your task is delicate, a kitchen cupboard job, or a beautiful piece of furniture with extra-exquisite joinery that you don’t want to take any risks with.
Fortunately, there are instruments available to measure the moisture level in your wood. The moisture meters fall into one of two categories: pin-type and pinless. Let’s have a look at each type.
- Pin-type moisture sensors/meters. These meters use electrodes inserted into wood to determine the moisture content and electrical resistance to do so. Take several readings with a piece of wood from your inventory.
- Water conducts electricity, while wood does not. Water has no resistance to the electrical current coursing through the meter, whereas dry wood does.
- The greater the resistance, the more water there is. The readings will tell you whether your wood falls within the dry range of 6% to 8%. A greater penetration of the wood will provide a more accurate wetness reading into the wood, as well as detecting any moisture pockets.
- Pinless moisture sensors/meters. Pinless meters don’t puncture the wood; instead, they have a sensor pad that reads the wood by contact with its surface. They typically have the ability to read moisture content to a depth of about ¼ – ½ inch. However, they offer the ability to conduct sample readings over a larger surface area more rapidly since you don’t have to carefully stick electrodes into the wood.
Which Is Better – Pin-Type Or Pinless Moisture Meters?
The pin-type meters, as the name implies, have a pin that punctures an absorbent material to reveal wetness levels. It’s helpful information when determining if additional drying is required and for how long. Pinless sensors have the benefit of taking readings on a larger surface area in less time. A pin-type is less expensive than a dial type, but it provides significantly more information. If you can poke the wood without interfering with your project, a pin-type might provide more detailed and precise information.
Are Moisture Meters Accurate?
When it comes to moisture meters, you get what you pay for.
More expensive meters will be of higher measuring quality and accuracy. A high-quality moisture meter from a reputable manufacturer can achieve 0.01% precision in determining the wetness of wood. Cheaper versions won’t even come close to achieving such accuracy.
If your project has a high tolerance for minor flaws, invest in a moisture meter. Fine cabinetmaking and furniture projects like these fall into this category and need that degree of precision.
Honesty is important: how many of you check the moisture content of the wood you just picked up from a lumber yard? Yes, you can rest assured that it’s dry enough for your project. However, if your project demands a high degree of finesse in the finishing, consider testing and adding a pin-type moisture meter to your list of essential woodworking equipment.
Does coating wood with oil stabilize the moisture content in wood?
Oiling the surface does not control the moisture in the wood. The wood will still react in humid or dry conditions.
The ideal moisture content for hardwoods is between 6% and about 9%, depending on the ambient conditions around the wood.
15% is too high, at least for hardwoods.
Softwoods typically have higher moisture content than hardwoods. 12% is good for softwoods, but again, it depends on the relative humidity and temperature where the finished product will be kept. As far as the oil finish, the manufacturer of the oil will specify the correct moisture content for an application.
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