Williams square nail and quarter test

[Dimefinder]

So I recently performed the square nail and quarter test on my collection of detectors, including the 705. They all failed. So, for anyone out there that is not familiar with this test, it's where you put a quarter on a clear patch of ground, put a 2 inch thick book on top of that. Next, make sure you can still detect the quarter. Then, put an old square nail on top of the book, directly over the quarter, and try to detect again. If you have a Williams detector, you can apparently mask out the nail, and still detect the quarter. None of my machines passed this test (705, deleon, F5 ).

It makes me wonder what I am missing when I keep passing up all those iron signals. How much trash over treasure am I passing by? Thoughts?

 

[Old Longhair]

IMO, anything but real world "tests" are meaningless.
I would also add that you likely can't say that the Xterra failed. You can likely only say that the coil/frequency that you used failed.

 

[Dimefinder]

Good point. I'd be interested in hearing if anyone has a combination that 'does' work.

Also, I wonder if the prospecting mode with iron made would work. ..

 

[Old Longhair]

Prospecting mode would be worth a shot.
You'd probably do better with one of the 3kHz coils, due to the poor response you get with it on iron vs the almost violent response 3kHz generates on silver & copper.

 

[Dimefinder]

Ok, I tried it with the prospecting mode, but no luck. Also tried altering the iron mask setting, and the EMI settings. Still no luck. I have the 6" MF coil currently on the detector.

 

[Mark in S.E. IA]

I'm with OLH on this one, that's not a real world test. That's pretty much a air and I do not believe in air test.

I have a X 505 and I use a 10.5 DD 7.5 coil and I can't tell you how many silver coins I have found over the years that had rust stains on the coin from a rusty nail that was touching it and it was a lot of them.

It's all in how well you get to know your MDer.

 

[Old Longhair]

I can't tell you how many silver coins I have found over the years that had rust stains on the coin from a rusty nail that was touching it and it was a lot of them.

Yep! Same here Mark. I spent all of one afternoon at a hard hit park digging nothing but deep coins that ALL had iron in the hole with them. Some stained, some not, but iron in every hole.

One reason that I don't buy simulated "tests", is because part of my machine's target response is dependent on Ground Phase. Without anything to balance to, the machine has a harder time assigning consistent/accurate values. I don't know what a book balances at, but I'm pretty sure that it isn't the same as my dirt. And I never go detecting with my Xterra at the library.

 

[mojotrout]

Hi, Im not responding to this to bash my Xterra 705, but Ive done real world tests, one in which coins are in the ground next to iron for years, and indeed the 705 fails. It fails with the 3 khz 6 inch coil, the 10.5 inch DD coil and the 9 inch 7.5khz coil. It also sometimes will give low (iron) tones on deeper silver, regardless of whether iron is adjacent to the coin. We've even tested two different 705s and have gotten the same results.

The 705 just doesn't perform well in iron, at least not in the moderately mineralized soil of the northwest. That doesn't mean its a bad machine, it does well in many situations. But its also important to recognize a detector's shortcomings and this is definitely one for the 705 in my neck of the woods. Perhaps there is a coil/setting combination that is best for the "nail test" that we didn't try.

 

[Dimefinder]

Thanks for that last comment. Also not trying to bash or rant. The 705 is my top detector, but to use it effectively, you have to know what it can and cannot do well, and what you can do to have it perform at its best in each situation. Part of the learning process I guess, and part of the fun.

 

[pasttom]

Maybe I am too picky, but I don't think any test is totally meaningless. I do think tests are nearly always taken too far in interpreting their significance with metal detectors. There are an almost infinite number of variables in all (and more so in 'real world' tests) that I don't see how one can do more than generalize. Even a well done test garden varies in humidity and several other factors. The there are settings and adjustments along with swing speed and ambient EMI variations.
I say all tests tell us something, no test tells us everything. I believe this is why forums like this one are SO VALUABLE! We get the varied feedback of a wide range of experience and conditions guided by very experienced moderators. We are all biased and prejudiced from our life and detecting experiences so there is always a grain of salt to flavor things, but isn't it fun?