What Problems When Coil Cover Fills With Saltwater Sand?

[ColonelDan]

I'm interested in what effects you have experienced when metal detecting at a saltwater beach and your coil cover fills with wet saltwater ladened sand and you didn't remove the coil to clean it out. Any falsing, degradation of sensitivity, loss of depth etc....what have you seen and where were those beaches?

I very much appreciate your input.

 

[cudamark]

The only problem I've had with my Excalibur 15" WOT combo, is the extra weight of the sand. No falsing at all. Now the E-Trac with the same coil, it will false from time to time, especially if it's wet black sand. I just pull the cover and rinse it off. No big deal. I haven't noticed any loss of depth or sensitivity, unless I turn that down to ease the falsing. I know what it is now, so, I just clean out the sand and continue running it full blast.

 

[Fletch88]

It's never been a problem for me. From excal, Etrac, CTX, Cz-21 to Sand shark and Dual field. Simply remove coil cover occasionally and clean.

 

[ColonelDan]

If you didn't remove the coil and clean out the sand...any issues there?

 

[cudamark]

On my E-trac, it would chatter a bit like you had the sensitivity up too high. I hunt in all metal with the Excalibur, so, maybe that's why I've had no issue with it.

 

[Fletch88]

I never had a problem but I only hunt FL beaches which are pretty mild from what I understand. Not sure about Cuda's Beaches in California.

 

[WaterWalker]

I have had the sand dry out, and then come out the the void onto the floors of the house and the rear of my van. Not much of a problem IF I clean it up before my wife sees or steps on it.

 

[Sir Gala Clad]

Wet/dry beach sand caught between the protective cover, aka skid plate, and the bottom of the stock 10 inch DD search coil of the Excalibur ll is such a problem for me that I seldom use the protective cover.

I limit the use of the protective cover, to where there are numerous exposed objects: rails/metal stakes sticking above ground, sharp ridged rocks, and dead coral. Under such conditions the protective cover is used more like a bumper so that the hard outside of the coil is not cracked if it bumps against a hard object rather than to protect the softer bottom of the search coil, which is more forgiving.

I have to periodically remove the sand caught between the bottom of the search coil and the skid plate to be able to distinguish targets.
:
When detecting with autosensitivity on - identify trash, especially bottle caps ) - about every one to one and a half hours.

With manual sensivity at seven detecting over dry and wet sand - about every two hours.

With manual sensivity at sub aqua (five and below) for shallow water hunting - about every three hours.



It should be noted that the degradation in performance is gradual rather than a matter of false alarms.
Simply put, it creeps up on you until it becomes too difficult to identify targets, until the trapped sand is removed.

I supect that much of the degradation is caused by iron the soil (heavily mineralized).
I don’t like to use magnets in my scoops as it is difficult to remove the black fuzzy particles often attracted while retrieving targets. Further, since the beaches are very narrow, the dry sand can be salty (conductive).


I have even more of a problem with the CTX 3030 as the ridges of it's search coils are are hollow which will accumulated sand even without the use of a protective cover. Unless I remove the trapped sand about every three hours, the performance will drop off. Most likely, the reason that I can detect longer before removing trapped sand with the CTX is I use a harness For hunting wet and dry sand allowing better control of the coil.

It should be noted that, I find the protective cover for the CTX 3030, especially for the 17 inch coil (a pain) to remove and replace.

 

[ColonelDan]

Sir Gala Clad, Thank you very much sir. This is just the kind of detailed report I was looking for and suspected as much in terms of the degradation of performance. I suspect it's even worse the more mineralized the sand.

 

[dewcon4414]

As the water moves the non-mineral sand out you will be left with black sand.... much like in a gold pan. Its not quit as noticeable in an Xcal because of the IM/salt setting.... but it will affect GB, depth, and cause chatter much like a bad coil. You tend to tune your ears to ignore it.....but you may well be ignoring deeper targets. A good indicator is after you get out of the water when you coil hits the dry sand..... it may false.

Dew

 

[Escape]

Not so easy taking off coil covers. Took one off after reading thread and cracked it evers so slightly, but enough that it won't hols on. Will try to fix it. Wonder how some of you remove them without damaging.

 

[cudamark]

I never had a problem but I only hunt FL beaches which are pretty mild from what I understand. Not sure about Cuda's Beaches in California.

We have some nasty black sand in some areas, especially when they dredge offshore and pump it onto the beach. Many of the areas I hunt, I grid from water to rocks, so, I'm going from in the surf, through the wet sand, up the slope, and across the dry to either the cliff or sea wall depending on the beach. My Excalibur with a 15" WOT handles that transition seamlessly (in pin point) with no apparent loss of depth or any chatter. I still dig 2 foot deep targets at the end of the hunt, just like I do at the start. I still find Jean rivets 10 inches down too. If I'm losing something with trapped sand, it isn't much, and probably nothing I'm going to worry to much about. Now, in the heavy black sand, detection depth is less, sometimes only half what you can get in the brown sand. Coil cover on or off doesn't seem to change that. The sounds are scratchier and many targets get an iron sound mixed in with the target sound. Unless it's a dead null sound, I scoop it. Sometimes I'll even scoop the nulls just to see what they are and verify my machine is telling me the truth. So far, after 8 years with this machine, and it's stock 10" backup, they are.

 

[ARC]

I solved this long ago...
By not using a coil cover unless I feel the coil will be harmed by the terrain.

When I first decided not to use one I noticed the slight "knocks" and "hits" the coil would take...
When finished detecting I would check to see if any damage was visible...
mostly none to light scuffs... which I did not like but can live with.

Fine tuning your swing into perfect EVEN swinging at a perfect height from ground of about 1 and 1/2 inchish will require no cover anywhere as far as I am concerned...
For me that is slightly higher than when with a cover... but not much... maybe half an inch.
BUT...
Accidents do happen... and occasionally I do get a "strike"... but hey that is the way it goes...
Not worth me constantly worrying about emptying sand etc.
And I have not damaged a coil to death yet (knock on wood)...
But I feel I have perfected my swing long ago.

Moving / twisting the upper body (like golf twist) with the arm can assist in an even constant "level height" swing without the "dip" in the coil to the grounds...
which is where the "hit" usually occurs.

My two cents.

 

[Sir Gala Clad]

As I damaged my shoulder while surfing a long time ago, I only use my arm/ harness to hold the search
coil above the ground and sweep the search coil by twising my hips (hula) while half stepping forward.
Or if I have the energy, and feel like being fancy, cross steppin will also cause the coil to sweep.
When the sand is level and slick enough, I often just skid the search coil across the ground for maximum depth. I would rather wear out a search coil than miss a finding a precious target(s) which will easily pay for any resulting damage.

But I feel I have perfected my swing long ago.

Moving / twisting the upper body (like golf twist) with the arm can assist in an even constant "level height" swing without the "dip" in the coil to the grounds...
which is where the "hit" usually occurs.

My two cents.[/QUOTE]

 

[Sir Gala Clad]

I have found the stock Excalibur ll 1000 coil, especially the bottom of the search coil which is softer to be surprisingly forgiving. The only damage to it in more than two years of use was caused by a large sharp granual of coarse sand which was became embedded into the softer underbody of the search coil and the protective cover, aka skid plate. The resulting dimple/dent in the bottom of the search coil turned out to be a blessing in disguise as it allows me to gauge the depth of scratches or wear to the bottom of the coil caused by scuffing against the sand while sweeping the search coil, which I have been doing for more than a year without any adverse effect. It is the sides of the search coil, you have to worry about cracking if you have to worry about cracking if you accidently strike them against something solid as they are more brittle/rigid.

I did not mention it, but mineralized/conductive sand building up on the top and sides of a wet search may also effect sensitivity / the ability to detect targets in the discrimination mode. The degredation is very gradual as the tones from the target and and what is under, above, and near the side of the search coil become difficult to distinguish - most likely they get blened in together. There is a small decrease in dectection depth as you go deeper in the water as the top of the coil senses the conductive water above it. That is the reason that you decrease the manual sensitivity on the Excalibur ll to the subaqua range 5 to a minium of 1 is recommended for shallow water detecting/diving.

Sir Gala Clad, Thank you very much sir. This is just the kind of detailed report I was looking for and suspected as much in terms of the degradation of performance. I suspect it's even worse the more mineralized the sand.

 

[ColonelDan]

Thanks to all who responded. I very much appreciate the input.

If a cover were available that protected the coil, did not accumulate sand, did not degrade the sensitivity or function of the detector in anyway, was of simple design, did not require silicon or marine epoxy to work and was readily removable, would that be useful? Seems to me that would be the perfect solution. What say all of you?

 

[ARC]

Agreed. Col Dan.

 

[ARC]

Working sand only beaches OR IN sandy water... IMO... requires no coil cover.

And mine stays in the trunk of the car...
just in case the terrain dictates the possibility of damage to coil without one.

 

[Sir Gala Clad]

My questions would be: how heavy is it, would sand be less apt to stick to the top and sides of the cover than the search coil,what would it cost, when will it be available.

If enough answers meet my needs , I would be willing to give it a go!

Thanks to all who responded. I very much appreciate the input.

If a cover were available that protected the coil, did not accumulate sand, did not degrade the sensitivity or function of the detector in anyway, was of simple design, did not require silicon or marine epoxy to work and was readily removable, would that be useful? Seems to me that would be the perfect solution. What say all of you?

 

[ColonelDan]

My questions would be: how heavy is it, would sand be less apt to stick to the top and sides of the cover than the search coil,what would it cost, when will it be available.

If enough answers meet my needs , I would be willing to give it a go!

Weight: same as your normal cover

Sand: does not stick to the outside surface any more than it does to your normal cover

Cost: Less than your normal cover

Availability: Stay tuned