Monte has a nail board test.
That is correct, I do have my Nail Board Performance Test, and I have been using this 4 over 27 years to evaluate different makes and models of detectors as well as different sizes shapes and types of search coils. Some detector and quail combinations can handle the ferrous nail challenges and others do not. They either qualify as passing to satisfy me and my wants and needs for hunting very dense iron nail contaminated sites, such as ghost towns, working around building rubble and renovation sites, etc. My Nail Board Test is not something that anyone can just randomly guess at by playing a different types of nails at different orientations to a coin. It is based on an actual, in-the-field encounter where, in May of '94, while searching a ghost town and evaluating a couple of detectors, I made my way up the little hill to the Old School site where you could look around and see an unbelievable scattering of nails a various sizes and shapes. I looked at the ground find a clear spot to ground balance, and right there a couple feet in front of me, laying on top of the ground like I have encountered many many times over the years I've hunted, was an Indian Head Cent surrounded by 4 iron nails of different sizes and orientations.
I evaluated the two detectors I had with me, ask three guys to check their detectors on this layout and a good friend of mine to check her Tesoro .... mainly to show the guys how a good detector with a 7" concentric coil can handle the challenges of Ghost Town hunting. I was taking notes and had my clipboard with me so I used a piece of paper to press on top of that display and Mark their exact orientation. I then picked up the Indian Head and nails and used them on a piece of cardboard from the back of my notepad to mark that exact orientation and glue them in position. I then had an exact specimen of an off-the-field encounter.
I contracted with a sign maker several years ago to make an exact copy of my Nail Board. Exact. I've been made a 'kit' using that exact layout and including for nails of the proper size to be secured in position so that others would be able to have an exact replica of what I encountered and what I use to evaluate metal detectors. That way, if anyone is using in exact position Nail Board set-up, then we can be great distances apart around the globe and their test results should be the same as my test results if we are using the same detector, and coil, and settings. The four different sweep routes are marked on the board so we can converse or discuss on a forum the results we get and it will all be done using an exact same position test setup.
Here is a test for searching in pull tabs. Place 4 tabs of your choice in a square and put a dime or coin of your choice in the middle where the diagonals cross.
This would be a fun test, for an individual to do just to learn something about their detector and their coil and their settings and their sweep speed.
However it is not a test as described that could be used by different people in different locations to make a fair comparison. Why? Because of this:
1.. You are asking people to take for pull tabs of their choice, and pull tabs have different alloy conductivities, and one person might use a Ring-Pull Tab with or without the Beaver Tail, or the 'Tail' could be bent in various positions, and then it's how you lay that Tab out in relationship to the coin. What you might do with for various shaped Ring-Pull Tabs will likely be different from what others will do.
2.. Some people might use a modern rectangular Pry-Tab, and again, those can be slightly different sizes and shapes and conductivities. I have one in my demonstration kit for my seminars that looks no different from others, but produces a rock-solid VDI read-out like a modern US Zinc Cent.
3.. With the different Pull- Tabs and no clearly marked and consistent size, shape, and type or uniform and consistent placement with relationship to the coin, all chests are not going to be consistent to make a fair comparison result.
4.. You suggest using a dime or a coin of an individual's choice to do the test oh, and right there you've added to the inconsistency that people are going to experience making that particular test invalid four different people, in different locations, to compare the results, of a different layout.
Gradually make the square smaller until you can no longer detect the coin. What kind of results do you have? What works best for you?
And with this it is going to be away for an individual to test various test samples that they select, with the whatever coins they select, using whatever detector and coil they choose just to find out how it may or may not perform. But at that point this type testing means very little because it is not going to result in a fair comparison that two or more individuals could make and then discuss.
Also to be remembered is that the nail Board Test is done using Iron or Ferrous trash and many detectors in use today we'll produce in audio "low-tone" or what we call an "Iron Audio Tone", and a higher tone for the higher-conductive desired target.
Your test is based on people using their variable discrimination control to reject the unwanted aluminum trash that shares conductivity levels with various assortments of desired coins, trade tokens, a lot of good artifacts and silver and gold jewelry.
It's no more than a suggestion for individuals to tinker with for their own interest and satisfaction, but it is nothing that would be uniform or consistent for two or more individuals to use for comparison from random locations.
Monte