# moisture and weight



## clippo (2 mo ago)

hi folks - apologies if this has been covered. Please point me in the right direction if so.

I've collected a few green sticks recently and I've been quite surprised by the weight. A couple of blackthorn staffs I've collected are well over 1kg.

Am I right in thinking that they will slowly decrease in weight as they dry (over 2-3 years I believe?).

This leads me to wonder if there are standard weights for different types of wood once dry? (even roughly?)

Assuming a blackthorn staff decreases to around 500g once dry (I've seen some on YouTube that claim to be this weight) does that mean that there's around half a litre of water (500ml/g) in a say, 1.5m length?

I was just trying to get a feel for the whole drying process really and wondered if monitoring the weight of a stick could be a useful guide as to whether it is seasoned or not...


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## dww2 (Feb 4, 2017)

I tried google-ing but couldn't find any info specific to blackthorn. Plus what info I could find on other species tended to be for logs not bits the size used for sticks. 


Yes, the wood will lose weight as it dries. Short of buying a moisture meter, there are a couple of ways to see if a stick blank is seasoned. The easiest is to tap it on a solid surface like the floor. A fresh stick will make a dull thud but a seasoned stick will almost ring like a bell.

Good rule of thumb is about a year of seasoning per inch of thickness. This will vary depending on location.

I found this chart which might be helpful. The weights (first two columns) are in pounds per cord, so not much help. The third column is the weight ratio of dry to green. The fourth the percentage of water. These are for species found in the US but I'm sure they aren't too different to those found in the UK.


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## louie.powell (Dec 15, 2021)

First, 'dry' is a relative term. Timber can only dry to the point where the moisture content in the fibers of the wood stabilizes with the moisture content in the surrounding atmosphere. Obviously, there will be seasonal variations in atmospheric moisture content, so wood that is considered 'dry' today may be thought to still be a bit green when the weather changes. There is no absolute standard of what constitutes 'dry', and it's anything but rocket science.

There are two methods that are commonly used to determine how dry timber is. One is to measure the moisture content with a moisture meter. Moisture meters report water content as percentages, but the numerical values are probably a bit flakey. A better approach is to compare the moisture meter reading with the reading from a reference specimen. You can set aside a scrap of wood in your shop to serve as that reference specimen, but some people simply use the wood top of a work bench as the reference since it's likely to be a permanent fixture in the shop. As time goes by, the reading from the subject wood should approach the reading from the reference specimen, and when they are equal, the subject wood is as dry as it is going to get unless you put it in a kiln and force dry it, but even in that case, the moisture content will eventually restabilize with the environment over time.

The other approach is to measure the weight of the timber. As time goes by and the wood dries, the weight will decline. The objective isn't to achieve any specific weight target, but to detect that the decline in weight has stabilized. When no further decline in weight can be detected, it is reasonable to assume that the moisture content has stabilized with the atmosphere.


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