Sube..Hi...Can you please post the 'Fatherless nail's' in-air VDI?

[metalpopper]

I'm curious about this rogue nail that you've experienced problems with.

If you have a sample, It will be of interest if you can positively identify its characteristics....IN AIR

Two sample readings...........North-South ______ East-West.

Passing the nail across the coil, at about 5 inches distance. (using open-screen,,,,,,,and Auto-sens)


THANKS,...matt.

 

[sube]

The fatherless nail will read the same in the air as any nail same vid as the others .This nail was leached to half it's original size so more iron was leached away leaving I would guess more conductive metals left .

But it still reads as the other nails . sube

 

[metalpopper]

The fatherless nail will read the same in the air as any nail same vid as the others .This nail was leached to half it's original size so more iron was leached away leaving I would guess more conductive metals left .

But it still reads as the other nails . sube[/quote

...................................​

Thanks for reply sube......

So am I right in understanding that 'it's the same VDI as other nails'..i.e.F35 C35/45 ....but reacts and registers on your 3030 in some 'false' manner, even when your 3030's disc pattern is fully programmed to reject it?

First point then, is related to your description of a bastard nail being one which is so corroded..(.or eroded ! ) such, that its normal metal profile is considerably reduced, and little conductive metal remains....yep?

2nd...I contend, that the CTX 3030, isn't / doesn't, give false readings or audio.....it's telling you exactly what the 'total effect' its search-head is experiencing.

If the targets in a complex situation, then so be it.....(or your pattern isn't sufficient for that particular case.)

Even digging a big hole and recovering items, will not necessarily allow an accurate assessment of the 'undisturbed' scenario.



In the case of a 'bad' nail, its VDI should reflect that fact....(That's why I asked if you had a sample of such a nail....for accurate VDI..in air)

e.g. A typical nail of say, F35 C45 normal value.....should change probably (guessing here)

...to something in the region of 25-27F 30's C....????

A reduction of ferro characteristics, and conductivity mass.

So perhaps your 'normal nail' pattern may require some degree of extension?

Not much more one can speculate about, but if I can find such a degraded nail, then I'll experiment ....in air...then buried

Thanks again for all your effort, and sharing same ....matt
.

 

[sube]

In the case of a 'bad' nail, its VDI should reflect that fact....(That's why I asked if you had a sample of such a nail....for accurate VDI..in air)

e.g. A typical nail of say, F35 C45 normal value.....should change probably (guessing here)

...to something in the region of 25-27F 30's C....????

A reduction of ferro characteristics, and conductivity mass.

So perhaps your 'normal nail' pattern may require some degree of extension?

Not much more one can speculate about, but if I can find such a degraded nail, then I'll experiment ....in air...then buried

Thanks again for all your effort, and sharing same ....matt




I don't think it well change it's still iron just smaller than original so it still should read 35.45 as to falsing if a nail is in the right position it's going to false that's just the way it is .sube
.

 

[metalpopper]

Quote......sube

[1]I don't think it well change it's still iron.....


[2]..... just smaller than original

sube, #2 is a contradiction of #1........and #2 is a significant factor.

A target's VDI is based on its mass, and the conductivity and magnetic permeability of that mass.

The Con. value should show a reduction, if the original mass of the nail is eroded.

The change/reduction in FE is a more complex factor for the detector to report.....Why?

Well; the value that can be assigned to ANY FE value is relative, and MAX-imised at 35, even

if its 100 or 300 in true dynamic magnetic units.

So the 'break-point' for FE 35 to alter to the next lower value, is not 'linear', nor easy to even guess

at.....you would have to experiment....Take a nail...read it...then keep shortening it in small increments

and record the FE and CON #'s,


Also, VDI figures are effected by the 'thickness' as 'viewed' by the lines of flux impinging

'normaly' onto the surface of the target. i'e....target orientation is a variable factor.

************​

Quote cont...

sube......'so it still should read 35.45 '

(matt....Not if it's been markedly reduced in mass...)

sube....as to falsing if a nail is in the right position it's going to false that's just the way it is .sube


sube, I think my interpretation of your term 'false', may be my problem in accepting aspects

of your posts....'False ' to me, means 'incorrect' in these discussions.....and I contend that the detector

doesn't false.....it's the interpretation that's 'false'.

I ask you;

If a nail is FE35 CON45 in air;

then what would its 'in soil' reading have to be, to rate it as 'bastard'? (i.e. false, incorrect, wrong.)


......matt

Thanks again for your points of view....matt....

 

[sube]

In the case of a 'bad' nail, its VDI should reflect that fact....(That's why I asked if you had a sample of such a nail....for accurate VDI..in air)

e.g. A typical nail of say, F35 C45 normal value.....should change probably (guessing here)

...to something in the region of 25-27F 30's C....????

A reduction of ferro characteristics, and conductivity mass.

So perhaps your 'normal nail' pattern may require some degree of extension?

Not much more one can speculate about, but if I can find such a degraded nail, then I'll experiment ....in air...then buried

Thanks again for all your effort, and sharing same ....matt

Matt for some reason nails or iron never get above the 32 line iron without a high conductor if the high conductor is covered east west with a nail then it will stay below the 32 line if not it well go above .

Now I have tried small nails 1/4 inch long and so forth all stay below the 32 line and of course they well show up on the 12 line as a good jumpy trace .

As to being 25-27 ferrous 30s c can't happen unless with a high conductor .

Now when a nail is hit and you look at the bottom curser sometimes it well change from 42 to 50 conductive does not matter size of nail what is important is where the trace is left 35.45 or 35.50 not where the curser is.

Now the fatherless nail would consistently leave a trace at 32.45 which is out of the 35 line that's why I called it a bastard nail but I found few nails that well read here most nails would stay at 34 to 35 line .

Now if minelab would expand ferrous and conductive numbers to a 100 for both I think vdi would be much more accurate on coins and iron .

One other thing if you watch my vid on the hot rock it places it in the corner 35.50 the same as a 10 inch heavy bolt WHY the rock is not as conductive as the 10 inch bolt but both go to the same vdi ?

You are correct in saying that iron is non linear

As to falsing yes it means incorrect as to the detector not falsing well you got a trace on the 12 line and good tone that to me says the detector is telling you it's good you be the judge . I know it's the iron falsing and not the detector but tone and trace is what we go by .sube