It's time for folks to report on their NBPT. :clapping:

[Monte]

Earlier this month I sent a dozen Nail Board Performance Test kits out to folks who volunteered to evaluate their detectors, and some borrowed or friend's models, on my Nail Board. Everyone therefore had an exact duplicate evaluation piece. The only differences would be in how each evaluator set their detectors up, and the search coil presentation (sweep speed and height from the nails and coin).

They were asked to do some 'testing' with various search coils, and also report on THEIR interpretation of how well the different detector and coil combinations performed. Some might be a little more tolerant of recovering a questionable response while others might only base their opinion on hearing a very solid and repeatable response from the coin.

I have asked the 'volunteers' to post their Nail Board Performance Test results on both this the Findmall Metal Detecting Forum and the AHRPS General Metal Detecting Forum. NBPT kits were sent to various USA states, to a couple of Canadian Provinces, and one to Slovenia in the EU.

I am sure not all of the results will be posted immediately as some might still be doing their evaluations due to weather delays, etc. Also, they had the option of individually posting their replies on both of these Forums, or e-mailing the results to me and I will then post the results. I know I am bury today and might not complete sorting through their e-mails and getting the results posted until late this evening or tomorrow (Nov. 1st).

You can be sure this evaluation is more challenging than just using a single nail or two placed and indiscriminate positions from the coin. This is all based on an actual in-the-field encounter at a Utah ghost town in late May of '94, and I have been using my NBPT to evaluate detectors ever since as part of my checking to see how well a model and coil might handle a dense iron nail littered site.

Please, feel welcome to contact any poster directly via e-mail or PM to get their personal opinion of their results. If you have any questions, feel welcome to ask here on the forum, or you're welcome to e-mail me directly and I'll try to help.

I have relied on this testing because I usually select very iron infested sites to hunt. On the NBPT I consider any detector that will provide 7-of-8 or 8-of-8 decent audio responses as a worthy consideration for hunting such a site.

There are 4 nails to just be rejected. Then a coin (US Indian Head or modern Zinc cent) is placed in the center circle marked position #1. The search coil is swept left-to-right and then right-to-left along four (4) sweep directions marked on the Nail Board. Two sweeps for each of four directions makes a possible eight ( audio hits possible for the coin.

In closing I want to send a 'Thank You' out to all of those who volunteered to help in this informative evaluation process, and I hope they enjoyed the educational experience.

Monte

 

[upfishcreek]

Hello Monte. Thanks for sending the board up here to Canada. Of course it snowed and my plans were thwarted somewhat but I did test my machines.

The Compadre with 8 inch coil hit them all. I just disc'ed out the nails and it hit your penny. I then ran all Canadian coins and they all hit 8 except dimes hit 6. The parallel sweep struggles on them.

Then I ran my Ctx 3030 and hit nothing. I reached out for some help because I'm new to the machine and when I got some advice it hit 6 solid and the other two parallel were iffy. I adjusted the settings again and hit 8 with the CTX stock coil. This was good but at the same time I realized I really need to learn the machine better.

The settings for the CTX were as follows. 2 tone FE. Fast on. High trash. Ferrous line set at 29 to low tone the penny. The trick to get 8 is use smooth audio. That smooth setting really picked up that coin no problem. I think the ctx with the small coil and these settings would be. Killer in a nail infested site now.

Before I figured out the ctx I was ready to toss it and use the compadre haha. Mind you I like the compadre but once ithe ctx was set I elevated the coils and the minelab really showed the depth ability.

So thanks again. This was an eye opener. Especially because the ctx stock modes did so poor. But once it was dialled in it did so well.

Bob in Calgary.

 

[Monte]

[size=x-large]Nail Board Performance Test results[/size]​

Detectors tested:

1. Garrett AT GOLD with 5"x8" DD Coil and 8.5"x11" DD Coil

2. Chinese metal detector MD-6006 with 6.5

 

[Monte]

He sent it to me as he had to hurry and fly out-of-town as his father is quit ill, but he'll check in when he returns.

Report from 'jackdaniels':
(I used 1906 Indian Head Cent).

Gold Bug2 with 6.5" coil-Sens max, Iron Disc on (up) & Mineralization Normal:
1 L-R Good Tone, R-L Good Tone
2 L-R Good Tone, R-L 2 Good Tone
3 L-R Good Tone, R-L Fuzzy Good Tone
4 L-R Good Tone, R-L Good Tone

With the following tests, he reported his results by the VDI Read-Out and the TID Icon indication. Note that he was using a 1906 Indian Head 1

 

[Monte]

[size=large]Monte's Nail Board Test Comparison Results[/size]

Tesoro Outlaw:

The 5.75" Concentric coil seem to hit well from every angle in both coin positions. It was a little "nervous" in the iron with a double beep at times
but hit solid on every swing. Disc just below foil and sensitivity between 9 & 10.

The 8" Concentric had pretty much the same results as the 5.75". Maybe not quite as crisp, but still hit every swing path every time. Also a little
"nervous" with the iron presence. Disc just below foil and sensitivity between 9&10.

The 10x12 DD coil didn't do as well. Still pretty impressive considering the coil size however. In coin position #1, it had some trouble with swing path #2 and #4.

In coin position #2, it had some trouble with swing path #2. Not quite as "nervous" in the iron but also not as crisp on the coin as the smaller coils. Disc just above foil and sensitivity between 9 & 10.


Whites IDX Pro No Mr. Bill Mods:

The 9.5" coil was just to big for good solid hits often double beeping on both coil edges. Still hit the coin on most swing paths, but not very well. It had the most trouble with coin position #2 swing path #4 giving just a quick blip. Sensitivity max, disc around the 10:00 o'clock position, normal mode.

The 5.3 Bullseye did very well. It hit every position with every swing with very "Diggable" responses. Again, disc around 10:00 o'clock position, max sens, and normal mode.


Fisher F2:

8" Concentric coil didn't do so well. Although it did hit on several swing paths, it was not solid. I would still dig these signals however as I know
when the F2 bounces around with mid and high tones, there is something there besides iron. The F2 also only has a segmented disc and loosing the first bar was my only option to eliminate the nails. The F2 disc's iron very well, so maybe having to remove a whole segment was too much disc? Sens at max and iron segment removed.

The 4" sniper coil did very well with the exception of a couple of one direction beeps only. Again, the F2 is not "nervous" whatsoever in the iron
and believe it would have done even better if the disc was segmented allowing for a little less disc setting.

I want to thank Monte for the opportunity to do this test. I still have alot to learn about this great hobby and this taught me some important lessons.

The video for this test can be seen at http://www.youtube.com/watch?v=m6mhJFzCThs. I'm no editing wizard so please excuse the quality or lack thereof. I somehow got the scene titles wrong on the IDX and the 12x10 DD Tesoro but was too late to edit again. Also, somehow i missed the upload for Tesoro 8" concentric with the coin position #1. Tesoro fans rest assured, It passed with flying colors. I will upload that one clip seperatley.

I think all in all, my results were as expected for the most part. Large coils not as good, Tesoro a little nervous but hits every swing, and IDX bullseye handling iron very well. My suprise was the F2 not doing as well as I thought. It is soooo stable in the iron, but like I stated above, I believe the segment disc doesn't allow a low disc setting for just "Barely" eliminating the Nails.

Thank You

Fred

Note: Fred did send a link to his video, but it obviously can't be posted here. Feel welcome to look it up or e-mail and ask for the link.

 

[Monte]

[size=large]Nailboard Test[/size]

Fisher CZ6a with 8

 

[Monte]

Surprising results to say the least. It was a real eye-opener. I would love to be able to provide this to you in a spreadsheet, but I don't posses those skills.

So, I'll try to create a table you can interpret easily. So here goes:

White's M6:
both 4x6 and Stock 9.5 coils.

Both 8 for 8.


AT Pro 5x8 coil:

------- L-R ----- R-L
1 ------ o ----- x
2 ------ o ----- o
3 ------ o ----- o
4 ------ o ----- x

7 for 8 (o=tone, x-no tone)



Fisher 1236x2 stock coil:

------- L-R ----- R-L
1 ------ o ----- o
2 ------ x ----- o
3 ------ o ----- o
4 ------ x ----- x

This was very interesting! With silencer off: 5 for 8 and with Silencer on: 8 for 8



Etrac Quick Mask (nails discriminated out - very slow sweep speed)

4.5x7 Excelerator:

8 for 8


Stock 11" coil

------- L-R ----- R-L
1 ------ o ----- o
2 ------ x ----- x
3 ------ x ----- x
4 ------ x ----- x

2 of 8


15" WOT coil

------- L-R ----- R-L
1 ------ x ----- o
2 ------ x ----- x
3 ------ o ----- x
4 ------ x ----- x

2 of 8


6x8 SEF coil:

8 for 8


6" Excelerator

------- L-R ----- R-L
1 ------ o ----- o
2 ------ o ----- o
3 ------ o ----- x
4 ------ o ----- o

7 of 8


Thanks for including me!

Phillip

 

[Phillip_in_NM]

Monte,

I really appreciate all the work you put into this and for sharing the results. I intended to omit the results I had from the ATPro since my proficiency with it is very limited. I just noted in your posting of my results that the table doesn't correspond with my grading of "7 out of 8". I rechecked my notes and the table is correct for a score of 6 out of 8 passes. Someone with greater proficiency on the machine MAY have better results.

Thanks again.

 

[deliveryboy]

Im a bit confused since there appears to be no universal grading system, each report uses a different method of reporting. The test idea seems great just need to find a simple universal way to report the results.

 

[Hombre]

Im a bit confused since there appears to be no universal grading system, each report uses a different method of reporting. The test idea seems great just need to find a simple universal way to report the results.

I think that the intent of the nail board test is to generate interest in doing the test for yourself. I found out years ago what worked for me in the nail beds around old home sites that I hunt at and it was an eye opener. The test is great for deciding which detector will report a coin surrounded by nails on the same plane, but when the coin is naturaly buried and a nail is placed on the surface above, what happens to the signal on the coin?

 

[Sleepyjim]

Am back father is got some things to get done(like a roto rooter job) but that will be here at home......

Worried but all is well....

Jim (jackdaniels)

 

[Monte]

I posted your NBPT below from AZ. I hope I had all the info correct. If not, please add anything to that post, if you would.

Monte

 

[azsh07]

I did this video for some other users who wanted to see how the new Russian detectors did on this test. I followed your instructions on your personal forum. Printed out the sheet and set it up as you instructed. I used some common nails and a few hand forged as rally I only find forged nails out here. If I am detecting in any spot with modern non forged nails..I am in the wrong spot..
I am not saying it did better, worse or the same as any other detector nor do I care to compare it to other units. It was simply a test.
The SIgnum has several audio modes so I chose to use those instead of swapping coils. I used the coil I use the most a 6x10 DD. I would never use a larger coil in nails.

[video]https://www.youtube.com/watch?v=RSFMxNY0j7Y[/video]