MMD4E moisture meter question/assistance

[Split]

Hi everyone. Recently, I purchased the mmd4e General tools moisture meter. My extra pins arrived today too. However, took it to the shed and just for fun checked some kindling I was cutting. I showed the wife vs some oak as well as a demonstration. After that the meter sits at a consistent 5-6%. I can't get rid of it. I calibrate and it reads properly (18.4-5%), so its working. But again I cannot get rid of the constant reading now of 5-6%. I tried many things: on/off, battery out for 60 seconds etc.

What did I do? Any had this issue?

Thanks.

 

[stoveliker]

Take the battery out? -ah you already did.

Are.you working in the right mode (wood and not building materials)?

Never had that happen with mine (3 years old now, used a lot because I didn't have really dry wood initially).

 

[Split]

Take the battery out? -ah you already did.

Are.you working in the right mode (wood and not building materials)?

Never had that happen with mine (3 years old now, used a lot because I didn't have really dry wood initially).

Odd. Checked this morning and now returning to zero, albeit not perfectly. It stutters on 5.6%. I wrote General Tools. Hopefully they respond.

 

[MEngineer24]

Odd. Checked this morning and now returning to zero, albeit not perfectly. It stutters on 5.6%. I wrote General Tools. Hopefully they respond.

I’ve never had this issue with mine either. Only bent pins, seems like the ones supplied with the meter are very soft. We have mostly hardwood here and i went through the original set very quickly.

 

[Split]

I’ve never had this issue with mine either. Only bent pins, seems like the ones supplied with the meter are very soft. We have mostly hardwood here and i went through the original set very quickly.

Yeah got back up pins yesterday. It's an odd issue and it can't e adding extra resistance because it comes up perfect in the test. Might be something loose. I'm patient enough gor a return if necessary. I'll try new pins today.

 

[MEngineer24]

Yeah got back up pins yesterday. It's an odd issue and it can't e adding extra resistance because it comes up perfect in the test. Might be something loose. I'm patient enough gor a return if necessary. I'll try new pins today.

Hopefully that fixes your issue!

 

[stoveliker]

I do think you could have a resisitive short; when the pins are open circuit and should read 0 pct, a short gives some current and it reads the 5 pct.
When you stick it into the wood, the current is much higher and the short doesn't add much (measurable) to the reading. (The current need not be linear with the moisture content, so that a higher moisture content will result in a muuuch higher current.)

Is it very humid there now? I've had shorts in measuring equipment due to adsorbed water films (in humid TN summers though, and with much more sending equipment).

What does it read right after you unscrew the pins?

 

[Split]

Returned for new unit. This is the unit I want and it has plenty of good reviews. It happens. Sometimes products have a defect. I'll keep the extra pins and battery for the hassle. lol. The new unit should arrive on October 13th but most likely before.

Bummer.

 

[DonTee]

Man I need to get one of these. I have a cheap MM from Harbor Freight, and the quality is not great (shocking I know. Lol).

 

[Split]

Man I need to get one of these. I have a cheap MM from Harbor Freight, and the quality is not great (shocking I know. Lol).

Funny how I'm returning mine as defective and you're saying yours is cheap. Lol. Actually the general tools one is rated by thousands of people so I know it has decent quality. I was just unlucky. I found it useful for the time I had it. I'm glad I got it. My new one is in the mail already.

 

[DonTee]

I think the HF version is like a 1/3 of the price of the MMD4E. And like you said, that one has a proven track record. One bad one doesn’t scare me off

 

[Split]

My new mmd4e showed up today. I put it to some use for two reasons. First my wood is a mixture of hardwood. Since most woods differ in seasoning time I want to make sure all is below 20%. I split some of my larger splits and all came below 20%. Most were in the 15-18% range. I stopped splitting after awhile and just accepted 99% was under 20. I want to save some larger splits for cold winter days. It was cool out today (albeit absolutely beautiful) so I retested some at room temp. Not a huge difference. The second reason is it's fun and interesting. I just don't know why I like it so much. I could axe and test all day.

What sucks a out the mmd4e is the pins that come with it are terrible. I bent the first set within minutes. I mean the pin tops literally curled over. I grabbed my back up set (from my last mmd4e) and by the end of the day they were bent too. I hope the backup set of four I bought will be better quality.

Some of my wood is quite dense knotty wood. They can really make a difference in weight.

 

[stoveliker]

Did you bend them while pushing in or pulling out?

I've used pliers to straighten pins. Though they are not as strong after having been bent.

 

[Split]

Did you bend them while pushing in or pulling out?

I've used pliers to straighten pins. Though they are not as strong after having been bent.

Pushing in. Last time I bent them cause of the angle I removed the meter. I was aware of that this time. But as I said they literally curled over. That is some cheap metal. Yeah I use pliers to straighten the pins if they get a bit wonky. I push them in the woofmd pretty hard. I want to get a good reading.

 

[stoveliker]

Not much we can do about that. Do try to measure in sections with straight grained wood. It'll be a bit easier and it's calibrated for that anyway.

 

[DonTee]

I noticed Home Depot has this meter and also the MM7. I wonder what the difference is.
Both made by General Tools.

 

[stoveliker]

I think the mm7 only is meant for building materials.

 

[DonTee]

Looking at the description for the MM7, it has modes for wood or building materials. With a range of 5-50% for wood, and 1.5-33% for building materials. Same range as the MMD4E it looks like.

Is the MMD4E advertised as being for firewood? The only difference I see (besides the MM7 being 5$ more expensive), is that the MMD4E says it’s accuracy is 3%, and the MM7 doesn’t list a tolerance range.

 

[stoveliker]

Maybe you are right. I looked into this when I bought mine a couple of years ago, and one only had scales for wood building materials (studs) , which is far too low for firewood.

 

[DonTee]

There’s less info out there about the MM7. Maybe it’s just a newer meter. Anyways, I just ordered a MMD4E.

I’m curious to see about the pins bending. I never had issues like that with my harbor freight meter

 

[ozarkoak]

There’s less info out there about the MM7. Maybe it’s just a newer meter. Anyways, I just ordered a MMD4E.

I’m curious to see about the pins bending. I never had issues like that with my harbor freight meter

I have the general also, pins bent the first few uses stabbing them into red oak. Harbor freight may get a bad rap on some products and deservingly so. But some of their products are worth a look.

 

[DonTee]

Looking at my HF meter, I bet it has the same style pins as the MMD4E. If I get mine and bend the pins, I might swap them out with the pins from the HF meter.

It might be nice to have both meters though. So I can compare the readings.

 

[Split]

Looking at my HF meter, I bet it has the same style pins as the MMD4E. If I get mine and bend the pins, I might swap them out with the pins from the HF meter.

It might be nice to have both meters though. So I can compare the readings.

View attachment 299954

Those pins look a bit thicker and more durable than I have on my mmd4e. I didn't use the second set of pins I purchased too much yesterday but of what small use they got the did not bend.

 

[DonTee]

I got my MMD4E today. It seems to test a little lower Mc then my harbor freight meter. I’m going to put new batteries in the HF meter and do a comparison.

The new meter came with an extra set of pins too. I can see where the pins they give you could be bent easily. They’re longer and thinner than the Harbor Freight meter pins.

 

[DonTee]

I did 3 tests with the GTversus the HF meter. I tested a piece of ash cut 3 months ago, and a piece of soft maple and cherry cut in the spring. So probably 5-6 months ago. All drying in the woodshed

Ash
HF- 22%
GT- 20.1%

Soft maple
HF-22%
GT- 21.1%

Cherry
HF- 22%
GT- 19.5%

And I’ll add a fresh cut and split piece of ash. About a week old

HF- 25%
GT- 23.1%