Hole in search coil?

[Neil in West Jersey]

Today I noticed a tiny hole in my search coil. I was using it in 4 feet of water and it was operating normally, so I wonder if it is just something I never noticed before. Is it normal?

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[bootyhoundpa]

i had recently noticed a 2 inch split along one of the edges of my excal 10 inch coil....my coil also operated normally and i would not have known the difference had i not given it a close visual inspection prior to vacation....the sand is just to abrasive on the bottom of a naked coil.... i fixed mine by digging out the few grains of sand and then putting a coat of pvc pipe cement on it,let dry 2 days,then i put the coil cover on it which i should have been using the whole time...

 

[Neil in West Jersey]

i had recently noticed a 2 inch split along one of the edges of my excal 10 inch coil....my coil also operated normally and i would not have known the difference had i not given it a close visual inspection prior to vacation....the sand is just to abrasive on the bottom of a naked coil.... i fixed mine by digging out the few grains of sand and then putting a coat of pvc pipe cement on it,let dry 2 days,then i put the coil cover on it which i should have been using the whole time...

I always keep a coil cover on. The marks you see must be from the previous owner.

 

[Critterhunter]

My friend's Excal has the seams splitting apart from sand wear around the edges of his 8" BBS coil. He used it that way with no issues but later I gave it 5 or so coats of spray on bed liner to protect it from further wear and to seal those seams.

Most coils these days are filled with epoxy. They only seem lighter because many (unlike the heavy old BBS coils) use what's called micro balloons mixed in the epoxy to lighten up the weight of it. Bottom line is that most coils won't let water get to the coil windings or the pre-amp chip on the BBS machines because it's incased in epoxy. I've seen some pics of BBS coils ripped apart with a grinder to reverse engineer them on another forum and even the pre-amp is under a thick incasement of epoxy.

I'm sure there are some DD spider web coils that might not be filled with epoxy but all the Sovereign/Excal Minelab coils and aftermarket that I'm aware of for them are filled with it. The old 8" solid Coinsearch coil wasn't I don't think. Don't know if the old white solid 11 (12?) inch S-12 coil before it became the webbing design it is now *maybe*. Coils not filled like the Coinsearch...if you get a hole in that in the water you might be in trouble I think. Some of the solid coils out there for other machines aren't filled with epoxy, more so I think then the web like DD coils.

That's why even if the coil nut isn't tight it might not be a problem, but then again why risk it? I guess water could wick down inside of the insulation and crawl into the windings or pre-amp or something that way. That's why I Shoe Goo the threads on them, hand tighten, and then tighten a hair more with a wrench. Not too much or it will crack.