Absolutely nothing ruins a very good woodworking project like gradual warping, shrinkage, or enlargement. Even though a wooden sort may look to be a wonderful select for flooring or furniture primarily based on aesthetics, what you actually need to have to concentrate on is dampness content. The wetter a wooden is, the more vulnerable it’ll be to warping.
Normally, it is effortless enough to examine dampness material just before using wooden for a venture. Just use a helpful moisture meter! But what if you missing yours or haven’t gotten around to purchasing 1 but? No subject – here’s a guide describing how to examine the humidity articles of wooden with out a meter. It’s simpler than you might believe.
Why Check Wood for Moisture Content?
The moisture content (MC) of a piece of wooden can impact that wood’s shape and measurement. As a hygroscopic material, wooden absorbs or loses dampness dependent on the ambient humidity of its setting. Additionally, wooden parts passively keep some dampness following getting felled – dependent on humidity, they may possibly at some point or never drop all this dampness.
In much more humid air, the wooden fibers suck up encompassing moisture – this causes wooden to broaden. In drier air, wood loses humidity. The reverse takes place as the wooden shrinks.
Wooden can also attain equilibrium humidity material or EMC, which happens when wooden doesn’t acquire or get rid of humidity.
Woodworkers might want to evaluate the MC of a piece of wooden so it does not shrink and warp after they use it. Hence, they could attempt to only work with items that will not grow to be too moist in excess of time. Equally, flooring installers may possibly want all of the wood items to be at an MC suitable for acclimation to their building’s ambient humidity.
What Types Need to Be Checked?
Specified kinds of wood hold much more moisture, both immediately right after currently being felled and in common. Broadly talking, heavier and denser wood varieties deal with more moisture or ambient humidity much better considering that they’re more resistant to warping or breaking above time.
Lighter woods need to be checked far more typically since they are more susceptible to substantial excess weight and condition alterations as their MC adjusts – their retained drinking water simply has much more of an influence on the condition of their fibers.
Wood Types That Need to Be Checked
- Maple – this wood is very popular in flooring and furniture. It commonly shrinks a bit when used in humid conditions
- Pine – although pine withstands shrinkage and warping well enough, it’s a soft wood that should still be measured for exact measurements
- Spruce – this wood is an excellent finishing type and resists decay quite well, but can also experience shrinkage frequently
- Cedar – this decay-resistant and rot-resistant wood often experiences expansion and shrinkage when exposed to higher humidity air, so its MC should be measured
Mahogany, walnut, oak, cherry, and teak are all reasonably resilient and hefty woods that resist warping and shrinkage really properly. It is considerably less essential to check out the moisture content of these wooden sorts, though it is by no means a poor idea.
How to Check Moisture Content
MC can be recognized as an expression of the weight of the h2o in comparison to the bodyweight of oven-dried wood, then multiplied by 100. Set merely:
- MC = weight of water/weight of oven-dried wood x 100
Understanding this formulation will allow you to check MC without employing a meter instrument.
The method would search like this:
- MC = 0.8/10 x 100, as 0.8 pounds of the pre-dried wood’s weight was water
- This results in an MC of 0.08 or 8%
The Oven Test
The easiest way to verify the moisture articles of a piece of wood is to weigh a piece of wood, dry it in an oven, then evaluate it yet again to see the variation in weights. This is the most correct way to take a look at MC in wooden, but it’s also time-consuming.
The oven for this measurement approach wants to be effectively ventilated, and the wooden will need to have to be dried for a considerable time period of time.
Step 1 – Flip your oven on to 220°F or related based on your oven’s heating talents. Yet again, make positive the oven is nicely ventilated, or use a kiln. The air flow is essential so the drinking water has a place to escape.
Stage two – Weigh the wooden whilst the oven is preheating. Publish the variety down.
Action 3 – Place the wood in the oven for 24 several hours. Weigh the wooden after this interval, then create the number down. The big difference in excess weight amongst the two measurements is the hypothesized “water weight”.
Action four (optional) – You may possibly want to set the wooden in the oven for another 24 several hours. If the oven-dried wood’s weight alterations, it even now needed to dry a bit. If it’s the exact same as just before, you know it’s fully dry. Heavier, wetter woods could require several days’ worth of drying just before they are completely ready for measurement.
Step five – Now plug in the formulation previously mentioned. As an illustration, say that the wood weighed 10 kilos just before oven-drying, then 9.2 lbs following.
Set one more way, the MC is the proportion of a wood’s excess weight created up of drinking water. The fat variation shows, out of a hundred%, how significantly of that share is/was moisture.
What is a Good MC for a Piece of Wood?
This is dependent on your setting and job. However, listed here are a few recommendations for basic MC wood amounts you must check for:
- Indoor wooden objects like furniture: 6-8%
- Wood to be used for flooring: 6-9%
- Wood for building construction: 9-14%
The “ideal” MC for a piece of wooden will also depend on the ambient humidity of the setting.
In the long run, checking the moisture articles of a piece of wood with no a humidity meter is reasonably uncomplicated, if time-consuming. Nonetheless, it’s very beneficial to have this method in situation your moisture meter at any time breaks. Bear in mind to preserve the oven ventilated and to select your wood for your undertaking meticulously – heavier, sturdier woods do better in humid environments in most situations irrespective of MC. Very good luck!
Showcased Graphic: PxHere