Most small coils are too big.

What would you consider the ultimate size coil for picking through heavy iron trash?

Apparently most detector and/or coil companies think that 5" - 6" is optimal.

The Gold Bug Pro 5" coil (which is really about 4.5") is the best small coil I've ever worked with. It gets a rediculous amount of depth for a small coil. Still I can't help thinking that a two or three inch coil might work even better. You don't need a super amount of depth in a high trash situation. I'm sure they could make a three inch coil that would get at least three or four inches of depth on coins.

If someone came out with a quality two or three inch coil for one of my machines I would buy it on the spot.

Does anyone else think a coil this tiny might be useful?



Edited 4 time(s). Last edit at 06/23/2012 08:49PM by Badger in NH.

Cut out a 2-3 inch circle in carboard to give you an idea and am afraid coverage would be very poor..Sort of like trying to paint the side of your garage with a small brush..

Perhaps could work for a real patient hunter....heck the 5 inch coil on my CZ doesn't cover a lot of ground and cut that in half...certainly not my cup of tea and imagine more would be made if marketting felt they would sell.

I was considering making one for my F75, for use on an intensely contaminated river foreshore, but I'm currently pursuing the custom pinpointer approach.
I presume a Sunray probe would count as a small coil, if you fixed it appropriately?

I had the hockey puck coil (350?) for my Whites's XL Pro. A nice coil for trash.

I also had the Shooter coil for my Prizm 6. Another great small coil.

These coils and other small coils like them have a purpose in my opinion. Heavy trash and iron. But I would carry a larger coil with me and change out the small one once I cleared the trash area.

They also help newer people to the hobby with pinpointing technique.

Now I have the Deus. The 9 inch coil that does not act like a 9 inch coil. The future of coils looks promising from a few manufacturers.

Tesoro used to make a 3" for the original gold Bug and it was a great coil for small gold.

Oops, It wasnt Tesoro that made it for the GB , twas Fisher, but I think Tesoro made one too for one of their detectors.

Hobo Wrote:
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> Fisher used to make a 3" for the original gold
> Bug and it was a great coil for small gold.

Yes, I thought I remembered seeing a 3" back in the 90's. Maybe a few companies made them.

I think it's about time someone brought them back.

It would be used for specific sites, mostly hunted out cellar holes which are often surrounded by a carpet of nails and debris.

I believe a 2" to 3" coil would be perfect.

I would like to see a 4" x 2" elliptical DD coil.

The coil I was going to make for the F75 would have been a scaled-down replica of the 11 x7 DD, probably around 3 x 2. Out of interest, is the 5 inch DD for the F75 actually 'round' or is it shaped like the 11 x 7 internally? Maybe shape is not so important with a smaller coil, and I can't help noticing the Fisher 15 inch coil is not a scaled-up 11 x 7.



Edited 1 time(s). Last edit at 06/24/2012 04:34PM by Pimento.

NASA-Tom Wrote:
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> I would like to see a 4" x 2" elliptical DD coil.

Me too, It would be awesome in a trashy area.

The 5" coil for the F75/F70/T2 is a round (concentric) DD coil.

Yes I like small elliptical DD's and even large elliptical DD's....

They really tighten thing's up..

A favorite for trash with the MXT is the 4x6 DD...Amazing coil..

Keith

some projects for NEL to bring to market maybe

NASA-Tom Wrote:
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> The 5" coil for the F75/F70/T2 is a round
> (concentric) DD coil.
How can a coil be both concentric and DD ? I always thought " concentric" refered to the coil windings (TX RX) being concentric and if it were a true DD it would be in a round housing and if the "Ds" were squished together it would be in a eliptical shape. Eliptical shaped coils can also have concentric windings and a round coil can be neither concentric nor DD (CZ 10"")

By definition..... you are correct. The 5" DD coil is round........... and not elliptical. Two opposing 'D' windings..... one is Xmit and the other is Rcv.

I've got a Sunray S-5 for my GT and it's 5.5" in diameter. It's plenty small enough. And I thought the bullseye Whites coil was a small coil, but that coil I think they call a 6" (or did they call it a 5.3" coil) but in reality it's like around 7" or so or something. Why can't these companies name the coil as the actual size! (shaking fist) I found that small concentrics smaller than about 8" do not seem to hold their depth as well as a small DD coil. The little S-5 I haven't used all that much yet, but I hit a rosie at 7" with it that banged so hard and ID'ed so easily that I think it could have easily been 9" or maybe even more and I still wouldn't have had a problem getting it.

That might not sound super impressive but you've got to remember in my sites that range from mild to higher minerals none of my non-Minelabs except one or two machines (the old low frequency Whites QXT and 6000 Pro XL) could make it to 7.5" on a silver dime. The 6000 Pro XL I think maxed around maybe 7", perhaps 7.5", but the QXT I felt had about a half inch tad more depth on a dime than it. So, it just blows my mind that the little S-5 on the GT is at least matching and sure looks like it's beating my "best" non-Minelab machines in my soil when those machines were using an 8 to 10" coil. That just makes my jaw drop.

I really don't think I'd want a smaller coil as the S-5 is pretty darn tiny at 5.5". In terms of length wise separation you can't really do any better than that. Now, oddly, in terms of the sharpness or left/right separation of the DD line, I think the 12x10 *might* have an even tighter DD line than the S-5. That's just a gut feeling, though, as I haven't done any tests to back that up with the two against each other.

I personaly don't want an odd shaped small coil. That's a trade off in seperation in order to try to increase depth by increasing the coil length. When I got to a small coil I want max separation, and that means the smallest round coil I can find. Now, in terms of a larger coil, I of course love the 12x10. Increased depth over a round 10" coil...with the depth of a 12" coil, but with separation that is BETTER than a round 10 or 12" coil and even probably easily better than say an 8" DD coil in terms of left/right separation...Due to the super sharp compressed with of the DD line via the unique SEF field being generated.

Flip a 5" coil upside down. Put a dime on top of it and surround it with nails. That is what the coil is going to see in the gound.

The 5" coil is not likely going to pick up that dime very well. I believe a two or three inch coil would work much better over that same area.

You can also do a test by laying a dime on the ground and puting a board over it with nails on top. When doing this kind of test, always make sure the nails are higher than the coin or they won't mask it properly.



Edited 3 time(s). Last edit at 06/26/2012 11:34AM by Badger in NH.

"When doing this kind of test, always make sure the nails are higher than the coin or they won't mask it properly.'


....ahhhhhhhhhhhhhh,,,,,,Now you're giving away some of our manufacturers advertising tricks !!....... To mask or not to maks ....This is the question !!.....Jim



BTW ....I hope this 2-3" coil comes with a chair !!.....

Tom ......A 2 x 4 eliptical would be a GREAT coil for trash ...... I could use something razor sharp like that down in the NYC parks with the massive amounts of trash that I find there ......Sometimes my 5 inch Sunray coils are too big !!.....Jim

Jim. Concur. . . . completely.

((( Still in need of a paradigm shift )))

synthnut Wrote:
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>"When doing this kind of test, always make sure the nails are higher than the coin or they won't mask it properly.'
>
> ....ahhhhhhhhhhhhhh,,,,,,Now you're giving away
> some of our manufacturers advertising tricks
> !!....... To mask or not to mask ....This is the
> question !!.....



Yeah, and the nieve fall for it every time.

I like the chair idea. Relax while you hunt. Kind of like ice fishing.



Edited 4 time(s). Last edit at 06/26/2012 08:20PM by Badger in NH.