Customer Reviews

HQRP JT-4G Wood / Firewood Moisture Meter - Wood, Firewood, Wall Damp Meter 4-Pins and Home Inspection Tool

5 star:		(3)
4 star:		(9)
3 star:		(2)
2 star:		(0)
1 star:		(3)

 

 

I bought this meter about 1 month ago because my firewood was not burning as well as I had hoped, and I wanted to diagnose the problem. I have found the JT-4G meter to be useful for this purpose.

I can't vouch for the absolute accuracy of its readings (I don't have an independent method for testing this), but at least the relative values make sense. My logs, nominally 16" long and mostly oak, maple and some birch, were split and dried for 1 or in some cases 2 seasons (in Massachusetts, during two unusually wet summers). The moisture readings at the cut ends are typically around 15-20%, which is within the recommended range for firewood. However, when I re-split them to diagnose the problem, I found a consistent pattern of higher moisture readings in the middle of the newly exposed surfaces (typically 25-30%). Thus, the meter has confirmed that my logs are drying primarily from the cut ends and that they have not been dried for long enough. Birch logs gave lower readings than oak or maple - perhaps because birch dries better or perhaps because the calibration of the device is not absolutely precise across different tree species. Commercial pine lumber (2x4's) gave readings around 5% or lower - ie much drier, as one would expect.

I also checked whether the orientation of the pins relative to the grain makes a difference, ie whether you align the long gaps with the grain or across the grain, or whether you stick the pins into the transverse cut such that they are parallel to the rain. In general my readings were consistent between the three orientations. So the orientation doesn't seem to matter.

The meter is easy to use. The 4 pins seem reasonably strong, although my intuition is that they could probably bend if I pushed with maximum strength. You do need to push a bit - I find that if they are not properly pushed into the wood, I get artifactually low readings. My sense is that once they are pushed in beyond 1mm or so, further pushing has little effect (that's important - the meter would be unreliable if the reading were proportional to the force, but once beyond a certain threshold I don't think this is the case).

Minor gripes - the yellow cap is difficult to remove, and the instructions are written in poor English, although the meaning is clear enough. It recommends checking the calibration by pressing it onto your fingertip - this worked as advertised. (I wonder whether the reading depends on skin conductance, and whether you could also use the device as a polygraph. But that's an experiment for another day....)

There are much more expensive meters available - I assume woodworkers who care about precision or about not scratching the surface would choose those more expensive models. But for testing your firewood this one seems to get the job done.

I bought this to check firewood and liked the price. I was actually suspicious of the price being so low but figured that for firewood I didn't need extreme precision or accuracy. It's easy to use and seems reasonably well built but as for accuracy, I have no idea. The instructions are written in pidgin English and are pretty useless. I think this instrument is fine for my purposes but if you are a cabinet maker, I don't know. They have e-mail support which I used and they answered quickly but not very informatively.

I bought this to test the moisture levels of my firewood. It seems to work well, I don't really have anything to compare it too so I can't say how accurate it is. I have some wood that was seasoned and it read that as around 20% and then I tested some recently split wood and it read around 35-40% so I am guessing it is correct. Be sure to split your wood in half before you test if you want a true reading. My only gripe is that the power button is just that, a button on the front and it is easily pressed, especially when putting the unit into the included case. This will kill your battery pretty fast, so I just leave it out of the case and put it in the toolbox.

I just bought a new EPA-certified woodstove and needed to find out why wood that burned fine in my old stove wouldn't get the new stove up to 400 degrees, which is the minimum I wanted to burn at. I bought this moisture meter, and it works just fine for firewood. If the wood tests at 25% or less, it burns great. If it tests at 30% or higher, it smolders, spits, and hisses. Plain and simple. If you need to know exact moisture level for woodturning or other projects, spend more money. If you want to know if firewood is ready to burn, this device is great and inexpensive.

Another reviewer states at the power button is easily turned on by accident, draining your battery -- this is true. Leave it out of the case if you're using it frequently, and take the battery out for longer term storage.

The Hold feature is useful. Stick the prongs into the freshly cut surface of the split, going with the grain. If you can't see the screen from that angle, press Hold and you can pull it away to view the percentage.

I purchased this meter to check the moisture content of my firewood. I gave it an honest try and apparently my wood is tinder dry because the reading is always 00% even freshly split! The instructions are a joke, can't even begin to describe there vagueness, or lack of english. As soon as humanly possible I will be shipping it back. I truely hope that I got a defective unit and everyone else's experiences are genuine. I won't be purchasing any more products from this company.

Matt in New Hampshire

Overall the product works, but is not very accurate. Difficult to penetrate the wood with the prongs. Really does not help much but another toy to use.

I use mine to check firewood before I buy and there is no doubt that it works well for that purpose. I split the wood to check the center and compare to firewood of same temperature that I know is dry. My seasoned oak/maple reads ~20% and burns great; but wood closer to 30+ range is a waste of money, time, space, and effort. I no longer mess around with wood that isn't ready to burn.

I agree with the earlier reviewer that I can't vouch for the absolute numbers, but the relative readings do make sense.

I never bother with negative reviews, but this meter is a complete piece of junk simply because it's incredibly cheaply made. Mine worked for about ten minutes. Save your money.

Bought it to measure the new solid hardwood floor I was planning on installing. It didn't read it at all. It didn't even read the plywood underlayment that I had in the house. It worked fine on a tree in my front yard....avoid this lousy meter unless you are measuing softwood or firewood and are you are OK with a +/- 10% margin of error. Plus, four pins were hard to insert. Dissapointing. Going back.

I bought this product to check the moisture content of firewood and it works fine.