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Exploring Iron Masking And It's Effects On Different Metal Detector Models


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I know there's already a bunch of stuff written on iron masking. But there might be some new readers that could benefit. Over on Monte's forum I started a discussion on iron masking didn't get a lot of response but Monte did write some very informative responses if you want to visit the topic on his site it's under the relic/old site hunting section. Here's the video.

Would love any additional comments on the subject if anyone would like to interject. I'm no expert and certainly don't know everything about every metal detector out there so I'm open to any constructive criticism or comments.

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1 hour ago, abenson said:

Monte did write some very informative responses if you want to visit the topic on his site it's under the relic/old site hunting section.

Link?

 

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Great video, illustrates lots of basic concepts.

I pay attention to coil size more than anything. A small coil on a slow machine will pick targets out of trash that a fast machine with a larger coil will miss. The Deus is famous for separation, but many slower detectors can cheat it by running much smaller coils than are available on the Deus. The bottom line is a coil sees everything that is under it at the same time. The detector can either pick one signal as being the strongest and lock on it, or it can average/accumulate things together into a single reading.

Dankowski Classics:

Beneath The Mask

The Painful Truth

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28 minutes ago, GB_Amateur said:

Link?

 

Sorry here is the link.

Iron Masking

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Pretty good test, as air tests go. I would have liked to know the individual settings on the machines to see if we're comparing apples to apples. Coil size is another variable that skews the test. The last test didn't show what the 11" Equinox coil would do, and I don't know what the recovery speed or iron bias settings were either. I often hunt around fire rings at the beach and find by moving the coil real slow with high recovery speed and high iron bias settings, you can pick good targets out of a carpet of nails. Not uncommon for me to get a slight high tone chirp among the iron grunts, scoop, and find a dozen nails in with a coin or other non-ferrous target. Naturally, the smaller the coil, the easier it is to do that, but, even with the 12X15" coil, I can still hunt effectively in that situation. You just have to really slow down and when you get a chirp, barely wiggle the coil to lock in on the good target. A full sweep won't do it.

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Interesting topic.  I just received my Vista X yesterday, with 11 and 6 x 8 coil. I replicated the test above with the 4  inch dime, and 2 -3" nails each 4" from the dime on the surface. I put on the 6 x 8 coil, and  I set the first disc level at 20. It low tones on the iron nails perfectly, but I could not get a squeek out of the dime.  Moving the nails away, it hammers the dime.  Now if I turn the coil 90 degrees, It detects the dime almost every sweep with the nails in place.  Next I removed the nails, and laid a staple on a piece of plastic directly over the dime, and the detector nails the dime every time. Hardly affected by the staple at all.  I did not get a chance to try the 11 coil tonite. I plan on doing a beach hunt tomorrow  with the x. A fair amount of iron is there, we will see how it does.  I sure do like the analog  on the X.  

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X.... may not be the best in 3D..Test according to me this Gold gain 30khz will do better ...

Now for the test .... Andrew you did another excellent comparison test of several detectors in your field ...

The truth is that not every detector also has a 3D separation predisposition and some detectors will do it better and others do not have such good assumptions.

2 D tests ... also show well the possibilities of separating a good surface signal in iron..and here is also important the ability of the detector to separate in this type of terrain .... in this type of separation, a smaller coil strongly helps .... so the detector can be replaced by a coil for a smaller one even "Improve" ..

Finally, if the detector handles well both 2D and 3D
separation  test at the same time on a single optimal coil ... we can consider it as one of the top detectors for separation ..

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13 hours ago, Redneck said:

Interesting topic.  I just received my Vista X yesterday, with 11 and 6 x 8 coil. I replicated the test above with the 4  inch dime, and 2 -3" nails each 4" from the dime on the surface. I put on the 6 x 8 coil, and  I set the first disc level at 20. It low tones on the iron nails perfectly, but I could not get a squeek out of the dime.  Moving the nails away, it hammers the dime.  Now if I turn the coil 90 degrees, It detects the dime almost every sweep with the nails in place.  Next I removed the nails, and laid a staple on a piece of plastic directly over the dime, and the detector nails the dime every time. Hardly affected by the staple at all.  I did not get a chance to try the 11 coil tonite. I plan on doing a beach hunt tomorrow  with the x. A fair amount of iron is there, we will see how it does.  I sure do like the analog  on the X.  

Did you try to set your first discrim to break on the iron? That usually helps me on my Tejon as iron will drag a target down so the result is you should get a beep out of it. You can also use your iron audio and when you hear a target, hit it at a couple different directions (set first discrim to 0, set the 2nd disc to break on iron). If the coil is too large the target may get smothered regardless.

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I always like the challenge of hunting iron infested areas. That is a good video and though I like all coil sizes to be similar it does show more of how the coils make a difference more so than the machines themselves, good overall look of what different people will run into with different machines.

ID machines I look for an up tic on anything above the iron range but skip stuff that spikes the machine to the max range. Iron can bring a silver quarter's number down to a penny or even a pull tab but wouldn't put those numbers in near max or max on the scale. As you get smaller and lower conductors or 3d masking the target will get smothered over and may only produce an iron only signal but may be a small target relative to the id #. IE if you hear a small dime size target but it has the iron number of an ox shoe you may want to investigate.

This is where I find a beep and dig to have an advantage not by technology but lack of. If I'm careful not to trim out the the fringe range than I am more likely to dig that target. Also I find a beep and dig to be more relaxing to hunt as I am not always trying to think so much hearing beeps, cross swinging over then and watching id's.

ID machines I like to run with Iron audio on in a disc mode setting so I can hear what is under my feet and know if I should be paying more attention to iffy targets OR I run in all metal mode and listen to the variations in the ground. Old Iron here in the NE can have some big halos and the old square nails can obliterate many coin size targets.

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8 hours ago, EL NINO77 said:

Finally, if the detector handles well both 2D and 3D
separation  test at the same time on a single optimal coil ... we can consider it as one of the top detectors for separation ..

Bingo!

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  • Steve Herschbach changed the title to Exploring Iron Masking And It's Effects On Different Metal Detector Models

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