FIREWOOD MOISTURE METERS , variation in moisture readings!!

[cessna]

I am very concerned about the consistency/INCONSISTENCY,  of  different makes  of moisture meter readings of moi(sture meters being sold to  sold to the general public to measure the moisture content of  the firewood delivered to them. I have an "EXTECH M0220"  wood moisture meter which as  been calibrated to measure different woods , to which you set the moisture meter to the relevant (A.B.C.E.F.G.H.J) as specified  in the chart accompanying the moisture meter (no D setting). 

Have any of you had a fallout with the "ODD" customer who when you arrive with their logs they  proceed to start prodding  your load of logs with "THIER moisture meter" , which reads higher than your moisture meter leading to  confusion!!! 

 

Edited September 28, 2020 by cessna

[Stubby]

8 hours ago, cessna said:

I am very concerned about the consistency/INCONSISTENCY,  of  different makes  of moisture meter readings of moi(sture meters being sold to  sold to the general public to measure the moisture content of  the firewood delivered to them. I have an "EXTECH M0220"  wood moisture meter which as  been calibrated to measure different woods , to which you set the moisture meter to the relevant (A.B.C.E.F.G.H.J) as specified  in the chart accompanying the moisture meter (no D setting). 

Have any of you had a fallout with the "ODD" customer who when you arrive with their logs they  proceed to start prodding  your load of logs with "THIER moisture meter" , which reads higher than your moisture meter leading to  whatever!!!!!!!!!!!!!!!!!! 

Some may find the above amusing,but I sadly think it may be a way to the future ,God Help Society !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I thought the future was Garlic Bread ?

[TuscanPhil]

11 hours ago, cessna said:

I have an "EXTECH M0220"  wood moisture meter which has been calibrated to measure different woods...

 

There's your answer - ask to see their calibration certificate when you show them yours.

[arboriculturist]

I think you will find that your Pin Moisture Meter measures on a 'dry basis', which is the wrong type of meter for firewood or forestry.

 

You need to obtain the correct meter that measures on a  'wet basis', which measures the water in the firewood (a solid), expressed as the weight of water as a percentage of the wet solid.

 

Pin Moisture Meters designed for the building trade are the wrong type for you.

[Paul in the woods]

Can't you just multiply the dry basis reading by 0.8 to get the wet basis equivalent?

 

In all this new legislation does it ever mention what basis, wet or dry, is used? Just curious as I've never seen it mentioned.

[Dan Maynard]

Minefield, I agree. Worse, because the moisture content changes, it matters when you measure it. Bit like prosecuting for blood alcohol.

We'll be having policemen putting samples of wood in foil bags and sending off to police forensic labs for analysis next. Only way to get a reliable accurate reading that can be used as evidence in subsequent enforcement.

[gensetsteve]

My meters fantastic can’t even get a reading off our kiln dried logs . O% moisture selling like hot cakes . I dare not buy a new meter in case it’s wrong ???

[neiln]

Should be measuring along the grain, freshly split surface, room temp log too, but yes the cheap moisture meters are merely a rough indicator

[arboriculturist]

19 hours ago, Paul in the woods said:

Can't you just multiply the dry basis reading by 0.8 to get the wet basis equivalent?

 

In all this new legislation does it ever mention what basis, wet or dry, is used? Just curious as I've never seen it mentioned.

 

19 hours ago, Paul in the woods said:

Can't you just multiply the dry basis reading by 0.8 to get the wet basis equivalent?

 

In all this new legislation does it ever mention what basis, wet or dry, is used? Just curious as I've never seen it mentioned.

No you can't.

 

 

 

Mwet = Mdry / (100+Mdry)    Mdry is the MC on a dry basis.

 

Yes it does - Firewood and Forestry - Wet basis - Always.

 

I have found the most accurate way to pin test to date is split the log, measure ACROSS the grain in the centre of the split face and at each end of the split face 2" (5cm) in from each end.

 

Measuring the outside of the log gave no usefull data that actually represented the actual MC of the log.

 

Add the 3 readings and divide by 3. When compared this result with oven dry method it gave reasonable correlation.

[Paul in the woods]

16 minutes ago, arboriculturist said:

 

No you can't.

 

Mwet = Mdry / (100+Mdry)    Mdry is the MC on a dry basis.

 

You've missed a * 100, so Mwet = (Mdry / (100+Mdry)) * 100.

 

But yes, I was wrong, as I was only thinking about the 20% wet basis limit.

 

So the OPs moisture meter can still be used, just need to convert to wet basis. If it reads under 25 dry basis the wood is under 20 wet basis.