Finderskeepers, ML, & Sovereignelite...Dug up some info that I read a while back that makes me believe this coil is indeed only rated water resistant for some odd reason, which is why I keep saying some people might consider it risky to use in the water. Also, down the post a bit on the white versus black thing from first hand experience with a coil...
Finderskeeper said:
I have hunted in fresh water with it and as far as being water resistant and not water proof, so far I can say that at the depths I use it, which is no deeper than 4 or 5 feet, (Average swimmers depths), the coil did just fine. I've not had one problem with water getting into the coil even after many, many hours in the water at those depths. Now if I were to dive with it, then I might worry. It sure would be nice if Detech would put to rest the worries of some by making a statement about the Ultimate 13's water abilities.
The one thing I don't like is the white color. It gets dirty pretty easily and is hard to clean. But I can see where in daylight, the sun could play a role in the ability of the coil to be stable as some White's users have found to be the case with the black Ultimate that was made for their V3's.
I have not used it in salt water as of yet but will give it a try this coming winter in Florida. I will also just in case bring with me the factory coil if it has a hard time in the salt water.
Can you tell us how it compares in the water drag wise to say the 10" Tornado or the WOT or any other coils?
Detech themselves only list the Ultimate coils as water resistant if I remember right. I had my doubts as to the reality of that, until I was told this straight from somebody who should know...
Critterhunter said:
Either way, anybody confirm it's only rated water resistant?
Bryce-IL said:
I can verify it Critter. I was informed of the fact directly by Doc of Coiltek during a phone conversation before testing the coil.
He stated it to me and also gave me the reasons why is wasn't waterproof and in fact was only water resistant.
That's why I made a point to also state it in my field test report in the magazine so people would know.
I did hunt in some drizzle/rain during testing and wanted to make sure anyone reading the article didn't confuse that with the coil being waterproof.
Coiltek makes the WOT coil for Minelabs, so I'm sure he knows what he's talking about. I also ran across a post where a guy was saying his would get freaky every time it got wet on another forum...
"Ive been using the ultimate 13 on my etrac for last two months...Just recently it started freaking out when it would get wet...! Would be forced to leave the wet up to the dry to calm her down. then when i would go back down...same thing..! I did not do my research first and assumed the coil would be fine in the water just like most are for that price! I guess I'm going to unscrew cap and clean out with a air hose...then shoe goo it up and see what happens...!"
I've read of people using it in the water without problems, so obviously there are two points of view on the subject. All I know was that when the grass was wet I was nervous with the loaner I was using, and I don't think I'll risk my future one being used in the water myself but others seem to be having no issues with that.
When you remove the coil cover on a coil and look at the bottom it's easy to tell when they are epoxy filled by the glass-like surface. When I looked at the Ultimate it has a grey looking material on the bottom. It didn't look shiney like epoxy but more like a plastic, and I'm not sure if it's filled with that stuff or if it's just a outer cover to seal the bottom. Doesn't look like epoxy to me, and Detech does say something like the coil is "injected under high pressure", so I'm wondering if it's using something different than epoxy to fill it to account for the super light weight for a 13" round coil and if that material might be more porous than epoxy, or whether it's in fact hollow inside. Way I understand it coils are only rated waterproof if they are filled with epoxy like the SEFs or Tornado's, so even if they have a breach in the casing water can't get to the vitals.
Used to be epoxy filled coils were very heavy but these days I suspect they use micro balloon technology mixed with the epoxy to lighten them up. Might be why the 12x10 is lighter than the 10" Tornado even though it's bigger. Solid coils that I've seen on machines usually aren't rated waterproof because they'd be too heavy if you filled them with epoxy. I guess the Minelab Coinsearch coil and the 5" Excelerators weren't filled with epoxy for that reason. Somebody recently posted some pictures of either a 5 or 6" Excelerator in the modifications forum that filled with water on him.
Detech now makes a black version of the Ultimate coil too...
[attachment 249025 detech_ultimate_coil_black.jpg]
At least some of the current Whites line up of machines (MXT, V3, etc) seem to have rather tight design specs and if a coil doesn't meet them tightly they get fussy. Probably why they make a white version of the 12x10 for the Whites that want V-rated coils. Maybe Detech just ran a batch out for that reason to meet the more picky tolerances of certain Whites and then used the material to make coils for other machines? Double DD coils are more popular among homemade coil builders for many reasons, but one of them also is that they are less picky about the alignment of the receive and transmit coils to each other.
I don't know off hand if the MXT/M6 models are as fussy since they don't need V-Rated coils I don't think, but I have read much more mixed reviews of the SEF coils being used on them compared to on Minelabs. Some think they are poor performers while others like them a lot. I know I've read of MXT/M6 users complaining about them here or there. One complaint being that some were having the coil PP off to the side like 2 or 3PM on a clock face, and people seemed to be having other issues with them as well that you almost never hear of in Minelab circles.
I owned a Hot Shot (Not Hot Head) 12" concentric coil for my low frequency Whites a while back. After 10 minutes it would go crazy. Thinking it was EMI, I'd throw it in the car and head to a new spot. Worked fine again, and then 10 minutes later it'd go crazy again. Sent it back for another new one thinking it was bad. Same experience with the new one, so I got my money back.
For years it stumped me what happened, until I was reading up on building my own coils and found out that in the hot sun a coil that isn't filled with epoxy is more at risk at having the tx/rx coils get too far out of alignment with each other and cause instability problems. Also found out concentrics are much more sensitive to the alignment of the two coils inside to each other. That coil wasn't epoxy filled (it was a solid coil design and mushy to the touch), and it was white, which I figure now was an attempt to keep it from heating up too much in the sun.
I'm not going to worry too much about the black version of the Ultimate and would prefer to get one over the white. Maybe all the Ultimates are indeed filled with a resin of some kind that won't allow the windings to drift out of alignment in hot temperatures, and yet whatever they used isn't has impervious to water seeping through it as epoxy? DD coils are more tolerant of misalignment of the windings than a concentric anyway. I doubt Detech would make a black version if it was going to have issues.
If I end up with a white version once the warranty is over I'm going to paint it top and bottom with 4 or 5 coats of spray on bed liner as the stuff gives it a factory-like finish. I seen it done with a WOT coil using Rustoleum spray on bed liner and it looked spectacular...
[attachment 249026 IMG_7081.JPG]
Using 4 or 5 coats of spray on bed liner on the sides and bottom of my 10" Tornado only added point two ounces (.2) in weight to it, so it was well worth the weight savings over the coil cover and also I hated cleaning under those. I use it on all my coils except the Sun Ray S-5, because I plan to trade it off.
