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Marc Jeske
08-05-2017, 11:35 AM
Recently got a like new Ligno- Scanner SD dual depth model from a fellow Creeker.

Having confusion using it.

I think most of my issues would be the case w most MC meters, probably not peculiar to mine.

Here's the PM I sent him...

"So went to the lumberyard, and got confused.

We don't have Dry hardwood available for 125 miles, a MAJOR trek for me, and most my work will be using "construction" SYP 1" stock, some 2" "SPF"

The main work I will be doing would be best w sub 10% wood, but what the items are, how they are constructed, it is acceptable.

So that's what I was checking.

At home, South TX, inside the AC'd house,various shelves made different times over a few years ago, all of SYP 1", showed around 8.5- 9.5.

So that sounds about right.

At the yard, I was getting readings on SPF "construction lumber" various 2x boards, weird thing was MANY were showing like only sub 10%, some as low as 7., that can't be right.

I would expect 15% +, up to about 19 for fresh stock that hasn't sat around.

But I think it was because I did not know for sure if the piece being tested was Spruce, Pine, or Fir, and which type of those also.

And the code #'s for this group of "SPF" wood ranges from about 34 to 64, so inputting the wrong code leads to wildly erroneous readings.

The code # chart shows Balsa as # 30, and Ebony as 84, so it seems the denser the wood, the higher the #.

Anyway, going to a different yard within few days where I will know the species.

Bottom line - I'm pretty sure the machine is totally fine, but turns out.. this definitely has a learning period.. And it seems absolutely mandates knowing species.... but then still also some level of experienced discernment.

And like ya, you get two very different readings if a board is unsupported on the underside, compared to in a stack.

It does say that in instructions.

Better know that, or you'll be chasing wild geese.

So pretty sure I'll be fine w it, pretty sure ALL the machines whether pin or pinless, have these idiosyncrasies.

So I feel this machine is fine, I just need to learn.

No way you could hand one to a new hire and say "Go check those different piles""



Any thoughts ?? Marc

Marc Jeske
08-06-2017, 1:05 PM
Nobody with these experiences ?

Any advice ? Marc

scott vroom
08-06-2017, 2:10 PM
I got a contact meter several years ago and took it along to the hardwood supplier. Got inconsistent readings from the same boards so now it sits in a drawer unused. Too many variables to get accurate and consistent readings I guess.

Marc Jeske
08-07-2017, 1:15 PM
Thank you Scott.

I'm experiencing similar, BUT I do believe it is just getting through the "learning curve".

I will persevere.


I'm really surprised I have had no more responses..... feel outcast.

Did I say something wrong?

I know many here have MC meters of various kinds.... pin, pinless, different Brands...

Did I miss something ?

Marc

Marc Jeske
08-08-2017, 7:08 PM
Going to different lumberyard tomorrow, hoping on some extra suggestions.

Marc

John K Jordan
08-08-2017, 9:30 PM
Going to different lumberyard tomorrow, hoping on some extra suggestions.
Marc

I use a Wagner pin_less meter. I've checked a lot of wood, much of it turning blanks and lumber from my sawmill. I air dry and expect about 13-15% around here but my shop heated and cooled so I see 9-11 for wood stored there.

Keep in mind that different boards or even different places in the same board can have different densities and give different readings. I check a board or block in multiple places to get an "idea" of the moisture. I can tell if a blank has reached or is close to reaching equilibrium. Although I do get different readings in different places on same board they are not that much different (unless I put it on end grain which always reads higher). Since I write the date on each piece I can compare similar pieces that have been drying shorter or longer times as a sanity check.

Have you tried the oven dry method of measure moisture? It's the gold standard in moisture measurement needing only a good scale and an oven. To give you more confidence in the meter (if warranted) you can make a few measurements with your meter on a board of a type of wood you often use. I'd keep away from knots. Then cut out those sections and use oven dry to measure the moisture to compare to the meter. If you find you can trust the meter and the variability in a given board is simply because of differences in the density, you might take a number of readings instead then average them.

JKJ