Iron Trash and Hot Rocks - Help!

[DFXer]

I've been detecting a cellar hole with my SE that is loaded with iron trash and hot rocks. The combination of the two ruins every trip that I take there.

Has anyone tried to discriminate out the hot rocks which always show up in the extreme upper righ hand corner? I can handle the iron reasonably well with Iron Mask.

Paul

 

[Jaichim24]

I'll be watching this post too, as after yesterday's hunt I was getting ready to post a similar request. I hunt an old mill site from the 1800's across the street from me, and it is full iron and hot rocks. There is so much iron in places that the SE trills, like it's near electricity. I hunted 3 hours yesterday and pulled bolts, nails, washers, crushed cans out. I did manage to pull out this copper/brass strip, that when I unfolded it and cleaned it I saw thermostat numbers on it. However, it goes up to 180+ degrees, so I'm assuming it was for industrial purposes. I also found a really awsome hammered nail with no rust on it. I'm not sure how it is possible. Anyway, between this mill site, and my house (1850 colonial cape style house) I'm getting really frustrated. I can't stop myself from digging the falses. However, in the SE's defense, several of my copper/brass finds were surrounded by iron nails or crushed cans.

Jai


P.S. Pulled my first tick off of me yesterday, everyone be careful and check carefully after each hunt!

 

[Dan-Pa.]

Try dropping the variability to 7 or so as rusty iron just has more of a shriek to it and seems to cover more area..Fortunately in our area hot rocks are unusual but if you listen closely and your tone variation hearing is excellent you may find a difference even though it is subtle. Although Normal in options response suited me fine never experimented with audio 1,2,3...but perhaps a forum member has which may help with a followup post..

 

[mattockman]

So the remedys are not the best but do help...but it will make you miss the deepies.....but you can cover it and pick a few oldies out and then if your tolorent enough then go back and hit it like a normal site....but with lots of patients
First....I try away from the main slaw of iron and hot rocks.....then as I work in closer to those I lower my gain to 6 and then lower the sens. till I get good enough seperation....if need be put on a smaller coil....go slower and when a hot rock goes deep in the right corner...it is usually a lot higher and tighter in the corner...if in dought check Conductive #...it should be 31 on XS so not sure what SE would be...Iron anyways....31 is Iron on XS....but the deep hot rocks drive me nuts cause they are lower but still sound like hot rocks..it is a diff. sound than silver....at least running var. 8 and th.hold tone 5 on XS. By also running with fast off that will help also. The hotter you have your machine the hotter everything else sounds....so by taming it down it will provide the seperation and stop the shreiking of the iron and hot rocks...of course you will be cutting the chances of the deepies but get the shallows out of the way.
There isn't any true way until all the rusty iron has dissapated away(Years and Years you will be dead by then I am sure) but the hots rocks will always be there....dig it all and then have a nice site but you will be dead from trying.....so either do what I say and cherry pick the shallows and walk away and find a better place or stay and die trying!!!!.......Good luck......

 

[mattockman]

I miss wrote: turn off fast....but I meant turn Deep off, but both should be off for stability.

 

[NH Bob]

Set your variability at 10. This gives most cut nails and Hot rocks a very squeaky hight pitched tone. Remember the arc that the variability setting represent. This is where more is better.

 

[DFXer]

Bob,
I can easily identify the hot rock sound but the question is - how do you prevent the sound from occuring?

A DFX has a function that allows - ACCEPT, REJECT or IGNORE hot rocks. Can a similar function be accomplished with the SE by setting a small discrimination reject block in the upper right corner of the screen and, if you do this, what are the consequences regarding masking a high coin signal?

Has anyone tried this? I may give it a try this afternoon if the rain stops.

Paul

 

[BlackX]

Was at a local beach on a pond where the sand apparently contained zillions of tiny hot rocks while I was testing the WOT I'd just received. Sweeps were nothing but bippity-bip-bip-bips. Nothing else I could figure out would make them go away, including dropping sense and gain way down, so I blocked them out with the smallest cursor via the learn function. Seemed to work reasonably well and I could detect without going batty.

I don't do it the rest of the time, even when hot rocks are bad, since I'm concerrned I might block out something good. I may try it some more though at a later point.

 

[GoldenRoyBoy]

Hello Everyone!
Interesting topic; and timely!

I've been working a small field near Trinidad, Colorado and it too is full of iron nails, fence wire, and those dreaded hot rocks! I like maxing my SE out, adjusting SENSITIVITY@32-GAIN@10-IRON MASK@20. I prefer adjusting SENSITIVITY manually. But, not here. I must rely on AUTO SENSITIVITY which does a great job. I check both FAST & DEEP hunting in ALL METAL. I've learned when my machine becomes unstable to simply turn it off, then back on without tampering with any other adjustments. Yesterday, I bet I did this a dozen times but it works, at least for me, stablizing the SE. I'm after the really deep stuff but being the field has been recently plowed the shallow finds are good too. Useing my 18 inch Excelerator, I have recovered finds at unbelievable depths. As far as the hot rocks, when I hear them, I dig them and bring them home! The property owner caught me as I was leaving yesterday and saw all the rocks. "What's with the rocks? he asked. "Oh, those are ringing up as gold, I thought I'd best hold on to them!" We both just laughed after I explained to him how his field was loaded with "hot rocks; weird anamolies Heaven created to drive us metal detectorists nuts!"

Enjoy the hunt!
GRB

 

[NH Bob]

I would not reject anything in the upper right corner. Most places that bother you with hot rocks are because they are plentiful. If that is the case, you stand too much of a chance of losing coin signals.

 

[DFXer]

GRB,
We seem to be on the same page. My SE goes unstable under these conditions and I just shut if off and restart.

I'm becoming a fan of auto sensitivity under a lot of conditions. I'm willing to lose some depth if only to get rid of the continuous noise which saps my energy.

Paul

 

[digitrich]

The only way I have found Paul is to listen to the QUALITY of the tone. A hot rock is more of a scratchy, screeching sound and big silver is more Round or Smooth sounding. So wear head phones and just watch your depth because if the big silver is deep (8 inches or better), it too, can make a screech sound instead of smooth. As for discriminating the hot rocks out, you could edit out the exact point 31-31, however, some of my best coins; 1850-1860 Seated halves all hit there, so that is something I will just never do. In fact, I almost past the first one up because I thought it was a hot rock!!!! One last point, some of those hot rocks can be meteorites and quite valuable. Save them, just in case. Don't you just love the final, definitive answers and solutions that everyone gives on these machines.

 

[digitrich]

Good point Bob, that might be why I can tell the difference on my machine, because I always run my Variability @10. didn't realise that until you just mentioned it.

 

[digitrich]

Check your gain setting too. A high gain almost amplifies the problem just like it amplifies every thing else. Auto sensitivity, a smaller coil, a gain of no higher than 7, noise cancel often, and having fast on and deep off actually helps to worsen the quality of the hot rock tone so it is more easily recognizable.

 

[BlackX]

[quote digitrich]The only way I have found Paul is to listen to the QUALITY of the tone.[/quote]

I didn't know he was lost. (Rumours from 40 years ago to the contrary--though his current ex- looks like she'd like to bury him.) Figured out what you meant after I'd first misread but figured what the heck...

Interesting that you're finding halves there. Good to know that.

 

[NH Bob]

How do you noise cancel the SE? In the air or on the ground?

 

[GoldenRoyBoy]

Hello Bob!
Since DFXer hasn't responded, I'll give it a go.

First thing I do is turn my machine on!
Then, I turned IRON MASK to OFF searching for an area free of iron.
Once found, I lift my coil approximately 12 inches off the ground and hit NOICE CANCEL, standing absolutely still.
I then play statue as people drive by waving, counting a slow eleven count. Presto, done!

GRB

 

[ED-NH]

My two cents: My Exll has the same issue more so with the WOT. I find that whenever I get the 'hot rock' signal that my cursor is buried upper right and also that my depth gage is almost all the way down (deepest). That is usually a good clue that this is a hot rock. The sound is always a solid high pitch whereas a large copper or silver coin when scanned very very slowly will waver a bit but I use audio 1 exclusively which drags out the signal anyway. I find that switching to auto-sensitivity makes a difference but depth is lost. So, I usually go with the sound, cursor and depth gage to make my decision to dig or not dig. I have not found a cure all method either.

 

[NH Bob]

I had the opportunity to talk with Sandy from Minelab a week ago. She was up for the weekend at the show and hunts we put on.
One thing I asked about was the noise cancel. She said the manual is wrong and your last noise cancel should be on the ground. Just like the old days with the XS and XSII.
Also, if you open the iron mask up to all metal or near all metal. You will have a better chance of finding clean ground to cancel on.
Point being, noise cancel on the grond helps cancel the minerals and lessens the falsing.
Remember, this is just my opinion.

 

[dewcon4414]

Ive not had anything comeing at digital 31 except hot rocks... so you might edit out 31 much like you would VDI 94 and 95 on the DFX when you are getting wrap around.