Moisture Meter Question

[Kenster]

Without debating, again, the accuracy of the meters I have a different question that I've not seen addressed. I know that you should always measure from the inside of a fresh split, with the probes running with the grain. BUT, how much different would your reading be if you stuck the probes into the butt end of a freshly cut round? For example, if I cut a downed tree trunk and wanted to see how dry it is, couldn't I stick the probe into the butt end to get a measurement that would be fairly close to what I would get if I split the same round?

 

[Intheswamp]

The meter is a simple resistance meter calibrated somewhat to a metering scale. I believe most instructions instruct that the two probes should be pressed as close as possible to the same vein/grain/whatever of the wood (with the grain)...supposedly measuring across the grain doesn't give an accurate reading and measuring the end of a freshly cut round would be measuring across the grain.

How much difference? I guess to find out ya gotta cut a green round, test the end and then split and test the fresh split.

Ed

 

[soupy1957]

Do a controlled test and chart it out, and YOU be the expert.........we're all ears/eyes.

-Soupy1957

 

[oldspark]

I did that last summer and the readings were the same, fresh cut end and fresh split=same thing on MM.

 

[Exmasonite]

Great post... a little more devil's advocate to play here:

InTheSwamp wrote: supposedly measuring across the grain doesn’t give an accurate reading

When we say inaccurate, is there any consistency to that? As in, against the grain always yields a higher reading than with the grain?

Just wondering if you get a reading of 20% AGAINST the grain, does that correlate to "15%" with the grain?

 

[DanCorcoran]

Great post... a little more devil's advocate to play here:

InTheSwamp wrote: supposedly measuring across the grain doesn’t give an accurate reading

I think that contention comes from the manufacturers. I don't know if anyone on Hearth.com has verified it (but maybe so?)

 

[Intheswamp]

Great post... a little more devil's advocate to play here:

InTheSwamp wrote: supposedly measuring across the grain doesn’t give an accurate reading

I think that contention comes from the manufacturers. I don't know if anyone on Hearth.com has verified it (but maybe so?)

To me is seems that according to the wood cell structure that there could be cell walls acting as electrical insulators between the water-holding cells when you place the probes across the width of the split. If you have several cell walls between the probes then the resistance would increase...higher the resistance, the lower the moisture content reported. Conversely, if you have the probes embedded pretty much running with the grain then fewer inline cell walls separate the probes and thus would not increase the resistance but show a closer actual resistance of the moisture with that close group of cells.

Oldspark mentioned that he uses his meter to check freshly sawn dead wood...he compared the mc meter reading from the sawn end it with a fresh split face from that log....he reports meter readings that are pretty much the same.....this gives him a good idea of how soon he can burn that dead and standing wood. It looks like we each kind of have to do some experimenting and see what our individual meters (and wood) do....and then use the readings to connect to what we actually experience.

Ed

 

[Danno77]

I've seen several MM posts recently where they tested on fresh cut ends and it was the same as fresh split inside measurements. My guess is that it will get you close enough if you want to know out in the field where you stand on a tree you just took down (dead or alive)

 

[pyper]

I was metering some fresh splits this morning.

I found that it didn't matter which way I aligned the probes -- for any given location I got the same reading.

I'm using a cen-tech meter from HF. It was only about $12. Neat thing it it has a thermometer function -- hopefully that indicates that the calibration is adjusted for temperature.