At the end of this discussion, you will be in a position to make a choice in the pin vs pinless wood moisture meter conversation. so, stay with me…
Every woodworker knows that a piece of wood’s Moisture Content (MC) is vital to every project’s success. Therefore, you must know the precise volume inside the wood cells before building.
Since it is impossible to determine the amount of moisture in the wood just by looking at it, you’ll need a wood moisture meter.
This device will give you precise or relative readings to help you decide whether the wood is ready for use or if you should give it more time to lose moisture.
There are two types of wood moisture meters – pin and pinless meters.
They have different features and working mechanisms, which you must differentiate to know which will be the best for your project.
This article discusses pin vs pinless wood moisture meters to help you make informed discissions.
A pin moisture meter has two metal prongs at its head, which you must physically insert into the wood to get the required readings.
An electric current flows between the pins then the device detects the resistance in the current’s flow to determine the amount of moisture.
On the other hand, a pinless wood moisture meter relies on an electromagnetic sensor pad to determine moisture content.
Unlike the pin-type meter, this one does not need to break the surface to get a reading.
Instead, you lay the sensor pad flat on the wood surface, and then it uses radio waves to scan the wood to determine the amount of moisture in it.
These explanations only give you the basics of how pin and pinless wood moisture meters work. So, let’s dive further into the specifics of each of them to help you understand better.
Table of Contents
What Is a Pin Wood Moisture Meter?
A pin wood moisture meter is a device that uses electric currents to determine the amount of moisture in a piece of wood.
It is called a “Pin moisture meter” because it has two metal prongs/pins that must pierce the wood’s surface to take a moisture reading.
When you insert the metal probes into the wood, an electric current flows between them.
The device then determines the MC by detecting the amount of resistance that the current encounters as it flows between the two points.
If the wood piece has a high moisture content, there will be little to no resistance to the electric current.
The reason is that water is a great conductor of electricity; therefore, if the wood has it in high amounts, the current will flow more easily.
Accordingly, the device will record a higher MC reading.
Conversely, there will be more resistance to the electric current if the wood has low moisture content.
The reason is that wood doesn’t conduct electricity well, so if it is virtually dry, the current will not flow easily. As a result, the device will record a lower MC reading.
Pin Wood Moisture Meter – Insulated Vs. Uninsulated
As you look through moisture meters in stores, you will notice that some have coated pins while others have bare pins.
The coated ones are “Insulated,” while the uncoated ones are “uninsulated.”
Both pin types will give you accurate moisture readings, but the insulated ones will give you a more precise reading. Let me explain.
The insulated pins are wholly covered except for the tips.
So when you place them into the wood, only the uncoated tips will touch the wood fibers, and as a result, you’ll get precise readings from different penetration levels.
Moreover, the moisture on the wood’s surface will not interfere with the reading.
On the other hand, uninsulated pins will detect readings both on the surface of the wood and inside the wood fibers.
So, before inserting them, you must first ensure that the wood surface is dry; otherwise, the moisture on the surface will interfere with the readings from inside the wood fibers.
Advantages of Pin Moisture Meters
The most significant advantage of pin meters is that you can collect readings from various depths within the wood.
The fact that you can get readings from multiple depths gives you better insight into the overall moisture content of the wood.
The pins come in different lengths; therefore, you can swap them as necessary to measure woods with different thicknesses – up to 2 inches.
Disadvantages of Pin Moisture Meters
Even though pin meters provide accurate results, you must test several areas on the wood to get it.
The reason is that the device can only detect the resistance between the two prongs – a very small area.
Hence, you need to collect more data from across the wood board to get a precise reading.
Another challenge with pin meters is the holes they leave on the wood’s surface. As you insert the pins in different areas, they leave tiny holes, making the wood look ugly.
Pin moisture meters also tend to break, especially when testing hardwood species.
The high density of these woods makes it difficult to push the pins to take a reading, causing them to break or bend.
If they do not bend, you may be unable to push them in far enough, and the readings you’ll get will not be accurate.
What Is a Pinless Wood Moisture Meter?
A pinless moisture meter is a device that relies on electromagnetic wave technology to determine the moisture content in a piece of wood.
Instead of metal pins, it has a sensor pad that you put on the wood’s surface to take readings instead of breaking the surface to reach the fibers.
When you press the device on the wood surface, the sensor pad sends electrical waves at a specific electromagnetic frequency.
As a result, it creates an electromagnetic field directly under the device up to 1 inch deep (depending on the device).
The electromagnetic field allows the sensor to detect return waves from the wood, which the device translates into a percentage of moisture content.
Advantages of Pinless Moisture Meters
The biggest advantage of pinless meters is that they do not damage the material because you only need to place the sensor pad flat on the surface.
There are no pins to create holes or burrows, making pinless meters the ideal device to test wood meant for furniture or any other project that requires a flawless wood surface.
Pinless meters also do not get affected by the wood’s density.
This is an advantage because you won’t risk breaking the device or getting false readings from pins not reaching the correct depth.
This type of meter can also scan for moisture in larger areas per reading compared to the pin-type models.
For this reason, you can finish your scans much faster, allowing you to move on with your project quicker.
Disadvantages of Pinless Moisture Meters
The most significant disadvantage of pinless wood moisture meters is that they only give you relative instead of precise mixture readings.
Therefore, you must compare the reading of your material to a reading taken from a completely dry version of the same material.
This comparison takes a little extra time and can be impossible if you do not have access to a dry version of your wood.
These devices can only take readings up to a fixed depth according to your model.
Unlike the pin-type models, you cannot collect readings from different depths to get accurate readings with a pinless moisture meter.
Pin Vs Pinless Wood Moisture Meters Comparison
Here we are going to differentiate/do a direct comparison between the two devices.
Working Mechanism: Electromagnetic Sensor Pad vs. Pins
The underlying working technology is the primary difference between a pin and a pinless moisture meter.
Pin meters measure the resistance to the electrical current that flows between the pin tips.
More resistance means that there is very little moisture in the wood; hence the electric current won’t flow easily.
Conversely, wetter wood will produce little resistance, which translates to a higher MC in the readings.
On the other hand, pinless moisture meters rely on a large sensor pad that emits electromagnetic signals to measure the MC of the wood.
This technology allows you to quickly scan large areas and get instant readings without the hustle of poking pins into the material.
Fixed-Depth Readings vs. Variable-Depth Readings
Pinless moisture meters provide fixed-depth moisture readings – 0.25 inches or 0.75 inches below the wood surface.
These depths provide the necessary MC readings to determine whether the wood is suitable for all projects, including flooring, making wood cabinets, furniture, etc.
To ensure that you get precise readings, you must pay attention to the amount of pressure you apply as you press the meter on the wood surface.
If you apply too little pressure, you might leave a slight gap between the device and the surface, which will interfere with its readings.
Therefore, the best way to ensure precision is to press the sensor firmly on the wood surface but not too much to break it.
On the other hand, pin moisture meters provide variable-depth readings because they read the resistance at the tip of the pins.
This means that if you don’t insert the pins correctly, you will not get the accurate moisture content of your wood.
This pin insertion problem can significantly hinder tests, especially if you are working with hardwood species.
Their high-density structure makes it difficult for the pins to penetrate to the proper depth hence the readings you get will not be precise.
Furthermore, the pins may bend or break if you try forcing them into the wood.
For this reason, pin moisture meters are best for testing the MC in softer wood species, while the pinless models work better with hardwoods.
Holes vs No Holes
A pin moisture meter must penetrate the wood’s surface to get accurate MC readings; therefore, each test will leave little pinholes on the material.
So, when you take multiple readings from different areas as required, you will leave a series of holes all over the materials.
These holes are not a problem if you’re working with 2×4 planks or when you’re testing the dryness of firewood.
However, it could pose a beauty issue in finer woodworking projects.
In contrast, a pinless moisture meter does not need to break the wood surface to get a reading.
You only need to press its sensor pad on the surface, and you’re set. As a result, there won’t be any blemishes on your material.
Meter Settings
Whether you’re using a pin-type or pinless moisture meter, you must enter specific settings to the device to ensure the accuracy of its readings.
Pin moisture meters are sensitive to temperature; therefore, all quality devices come with a temperature correction chart to guide your settings.
They are also sensitive to the wood’s chemical makeup; hence your device will always ask you to indicate which wood species you are using.
On the other hand, pinless moisture meters are only sensitive to the wood’s specific density, which varies from species to species.
For this reason, you must enter the correct density setting before taking measurements.
If your device doesn’t have the feature that asks you to specify wood species, ensure that the manufacturers calibrated it to the douglas fir.
The douglas fir is the most widely used species for wood projects; therefore, its settings will give you readings with little margin for error.
Speed
Taking measurements with a pinless moisture meter is much faster than when using pin meters.
The reason is that the electromagnetic sensor on pinless meters scans a large surface area in one swipe allowing you to finish tests faster.
If you use a pin meter, you will need to test several points to cover the same surface area, which takes longer.
Does Surface Moisture Affect Wood Moisture Meters?
Pin moisture meters that use pins with long insulated shafts aren’t affected by moisture on the wood surface.
The shaft insulation keeps the pins from getting readings from anywhere else apart from the tips that touch the wood fibers.
Devices with uninsulated pins are most vulnerable to surface moisture interferences.
Pinless moisture meters are also affected by surface moisture but not as much as those with uninsulated pins.
When there’s some condensation on the wood surface, the moisture reading will be about 5% or 10% higher.
On the bright side, these errors are avoidable if you wipe your wood to remove the condensation before every test.
Do I Need a Wood Moisture Meter?
A wood moisture meter is a must-have in your tool belt if you are a hobbyist or a professional woodworker.
Besides checking the moisture content of your wood, it will also significantly impact your woodworking endeavors.
To help you understand better, I’ve compiled a list to show you why woodworkers must always use a moisture meter.
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Moisture Meters Improve Efficiency
Some hobbyists use home moisture tests like the “water test,” but they are highly unreliable.
For this reason, you must use a wood moisture meter to get quick, accurate readings on all your building materials.
If you don’t have a moisture meter, you will have to “eyeball” your wood to know whether it is dry enough for use or not.
If you use a moisture meter, you will get precise numbers that show you whether your wood is ready for a project.
Moreover, you won’t have to wait hours or even a whole day to get results; hence you can start and finish your projects faster.
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They Ensure Quality Control of Products.
A moisture meter is necessary if you want all your wood products to last and conform to high-quality standards.
The readings you get from them will let you know if your wood is acclimated to ensure that your end products won’t fail due to moisture problems down the line.
If you use wood that hasn’t dried properly to make something, say a table, it will continue drying even after completing the project.
As it dries, the material will shrink, resulting in dimensional changes in the table, which diminishes its quality considerably.
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They Document the Process
Some moisture meters store digital readings, which you can refer to later as needed.
It will allow you to document your quality control process with the date and time stamps, giving you the ammunition you need in case someone questions the quality of your products.
Sometimes, customers return products to woodworkers’ shops after they get damaged during use, expecting a refund.
However, if you have these records, you can prove that the problem came from the user’s end, shielding your little home practice or business.
Conclusion
Pin and pinless moisture meters are the most common devices that woodworkers use to determine the MC in wood before projects.
They give accurate results allowing you to create quality items that won’t fail because of moisture problems.
Selecting between the two can be pretty challenging, especially if you’ve never used a moisture meter.
They have different working mechanisms; hence you must understand…
Pin Vs Pinless Wood Moisture Meters
Pin moisture meters need to penetrate the wood fibers to provide precise moisture readings; therefore, they have two metal pins to poke the surface.
They measure the resistance to the electrical current that flows between the two prongs to determine the amount of moisture in the structure.
On the other hand, the pinless models have an electromagnetic sensor pad that you press lightly on the wood surface to get readings.
They do not leave blemishes on the surface and hence are appropriate for fine woodworks like making furniture and cabinets.
I hope you understand the differences between pin and pinless wood moisture meters.
If you need me to clarify anything or have any more information to share, feel free to reach out in the comments section.