Shielding a coil with galvanizing zinc spray?

[MDfanatic]

Title says it all, has anyone tried to shield his coil with galvanizing zinc spray?
If yes, what were the results?

[Tinkerer]

Title says it all, has anyone tried to shield his coil with galvanizing zinc spray?
If yes, what were the results?

I tried. Also tried Zinc paint that contained a very high percentage of pure metallic zinc powder. The results were not good.
This was about 20 years ago. Don't remember the reason of why it did not work well. Don't remember if I properly understood the reason either, but remember putting it down to the Zinc particles oxidizing and not making good contact among the particles as well as with the drain wire.

Maybe it is worth trying again?

[MDfanatic]

Then I'll have to bite the bullet and make two identical housings with different shielding material (zinc and graphite spray) and check the differences on ground and by measuring detection distance I suppose.

[surfdetector]

I am curious as to why you are not going to do a foil or mesh wrap of your coil for shielding rather than using spray? My latest mono coil I left unshielded and I have experienced no problems although I only use my PI in the ocean as opposed to the land.
Cheers

[MDfanatic]

All the coils I've made are unshielded as well but I'm curious about the effectiveness of different shields because the soil where I live is "hot" and I get a lot of false positives. I don't MD on beaches.
I have already tried the foil shielding but not the mesh (any info would be helpful). Any other info about other types of shielding is welcome though, I'm always eager to experiment

As for your question, I don't have a preference over "solid" or sprayed shielding, it's just a matter of experimenting and easiness of application.

[surfdetector]

Have you read the paper "Making a Fast Pulse Induction Mono Coil" ? If not , I can tell you that it is a treasure trove of information about mono coil construction including shielding.
You should be able to find it through a forum search, if not I can email you a copy.

Cheers

[waltr]

All the coils I've made are unshielded as well but I'm curious about the effectiveness of different shields because the soil where I live is "hot" and I get a lot of false positives.

Hot soil requires a Ground Balance (GEB) method. Coil shield does nothing for hot ground.

Have you read the paper "Making a Fast Pulse Induction Mono Coil" ? If not , I can tell you that it is a treasure trove of information about mono coil construction including shielding.
You should be able to find it through a forum search, if not I can email you a copy.

Cheers

It is here and a very good read:
https://www.geotech1.com/cgi-bin/pag...oils/index.dat

[kt315]

https://www.geotech1.com/forums/show...MiniPulse-Plus

[ZED]

In hot ground a coil shield is compulsory.

[Polymer]

I am curious as to why you are not going to do a foil or mesh wrap of your coil for shielding rather than using spray? My latest mono coil I left unshielded and I have experienced no problems although I only use my PI in the ocean as opposed to the land.
Cheers

Hmmm, I had to shield my monocoil for the beach & wet sand, maybe its different under water, if you meant that?
What timings are you using ... Pulse width, sample delay etc.

[surfdetector]

Hmmm, I had to shield my monocoil for the beach & wet sand, maybe its different under water, if you meant that?
What timings are you using ... Pulse width, sample delay etc.

I usually hunt in the water, I will check my settings later but I did match them fairly closely to what was shown for a slow coil in the back of the build document.
Cheers

[6666]

https://www.geotech1.com/forums/show...713-Zinc-spray