kac

You may want to snag Inside the Metal Detector found here:

https://www.amazon.com/Inside-Metal-Detector-George-Overton-ebook/dp/B01N8WAG7L/ref=sr_1_3?crid=3B20YBN072KAW&keywords=inside+the+metal+detector&qid=1704764653&sprefix=inside+the+metal+%2Caps%2C97&sr=8-3

Should have some very helpful info and math needed for designing those coils.

Very cool. Gems are probably worth much more but getting them gia certified is around $100 per ring so a little investigation first can save quite a bit.

Don't rely on the acid tests, they are an ok ballpark but I am finding the test kit I have seems off. In particular the 14k solution seems too strong so many of the stuff I find tests at 8k even latest bracelet chain i found that was clearly marked 14k.

On 1/4/2024 at 9:26 PM, F350Platinum said:

Nice coin kac! 👍

I too like the fancy button, you sure have some nice places to hunt. I do remember the terrain up there though, it must be difficult sometimes. 🤔

Grounds not difficult, we just tend to lose a lot of depth in some areas due to mineralization. Narrow dd's tend to do  fairly well but it's a balancing act wtih depth, coverage and separation. Can't have all that in one coil.

16 minutes ago, F350Platinum said:

Thanks kac,

I did search the dirt I dug out, looks like the stone separated from the ring long ago, the clasp is mangled. Could be anywhere.

Dig more dirt, eventually you may find it 🙂

Blew off work for a hour and hit one the permissions I have nearby. Was working an area where I had plucked some other oldies out and sniffed out this nice little 1877 seated dime. Turns out to be a S which I don't see to many on the east coast here. In the mix there was some tiny signal which look like rivet heads to clothing, probably turn of the century.

Also kept running into some deep targets that had a faint iron audio or nearly none but would have a low TID. Out of curiosity I carefully dug a couple of them and came up with lumps of iron oxide. They weren't very heavy. Out of curiosity I gave them a good squish in an arbor press only to reveal what looks like carbon in the middle. My guess is the iron rusted away leaving the carbon  behind. This would explain the coal like behavior and rusty lumps. The longer piece you can see the layers. Guessing it was a piece of an old horse shoe or something similar that was forged.

You should go back and sift the dirt where the ring was and see if the stone is there. Bucket of water and course screen should do the trick.

Hopefully it isn't your best find for the year we got a long ways to go.

As for the Sea Hunter, you can use the MS2 headphones if your not diving. Better audio and volume adjustable, much more comfortable.

I like the SH and especially the 10x14 for beach combing. I had slapped a part whites, ml, garrett shaft together and put the control box under the arm cuff balancing it perfectly. Downside its still close to 6 lbs and if your have a bad shoulder this will limit your time hunting. There is the hip mount that works but any movement on coil wire can cause it to false a little.

Most sandy beaches or where there is black sand, hands down its far better than vlfs but there are areas I hunt that have so much iron trash that it would be impossible to dig everything. Sounds like a valor attempt at greatness but a daunting task that would leave you with a trash barrel of crap and only cover a small area.

I'm not a die hard beach hunter and prefer vlf's when possible.

I have an MK2, very stable machine. 8" mono is ok but not very deep on small stuff but from what I have seen its similar to the Sand Shark. 10x14 is a beast but likes to rise up unless you mount the box in front of your hand.

I don't use mine much due to brutal undertoe we have here and all the lobster trap bits.

As for handling black sand and hot rocks its a champ.

Reason you need a pi other than black sand? Been using D2 24khz smf and smaller scoop here. More enjoyable not digging everything and having a light setup.

Do want to mention the D2 dive mode has crap depth, could probably modify the beach sensitive like I did and it does very well.

Half a penny is worth more than none 🙂

Great posts Bob, maybe next year you do better, if that's possible!

Gonna have to dig through the ones I got and see if I have any other than 64 or 65.

Large iron and flat iron will always produce a signal in the upper range. If the ground is moist you can pick up iron tone off the edge of the coil. Another thing you can do is do a slow pass with coil over the target and the iron will be more evident. XY screen will also show whats going on.

I set my discrimination to 0, I don't use bcap or any other notch filtering, silencer at a minimum and iron will be easier to identify.

Try cleaning it up a bit more on the back and see if the 2 cent is small or large moto. Small moto have heavier letters.

Think most my 2 cents are 65's but believe I have a 64 too but its a large moto.

Be curious how it would do against a GPX or Axiom with similar sized coils. Even against other machines like the Nox line or D2.

Wouldn't be surprised if performance was similar.

Still a cool machine but non motion might be a problem in high aluminum trashy areas.

I see parts of a hurricane lamp in the mix. Some nice finds there.

Good sign for things to come.

Too many tones can wear you down. Try simple 2 tones with a moderate break. I modified the High Conductor with no discrimination and tone break around 25 and 14khz works well in hot ground.

If I get any falsing I usually slow my swing speed.

Nice knives, the seated probably gives you a guestimate on age of knives. Very cool.

If the machine has good audio modulation then you can judge older targets by depth over the superficial trash.

Hunting around properties the trash I run into is usually bits of flashing sometimes foil from bbq's that met its match from mowers. I tend to listen for the deeper stuff.

Machine looks promising. I would like to see it in action in a real world hunt where iron infestation is an issue like old barns, cellar holes etc. and where people dumped their burned coal. I'm less concerned over highly mineralized soil here because that is generally near wetland and not where there would be high concentrations of refined iron which is more of an issue.

Open fields iron contamination isn't as concentrated and targets much more spread out. There are many machines that would be tough to compete with in those conditions. I tend to hunt where the higher concentration of activity was first. Those areas are brutal with new machines.

If it can pick out a silver dime 8"-9" in mild ground then I think you got something there.

8 hours ago, NCtoad said:

Here’s my scoop.  Plenty strong (and heavy), but even though it’s small compared to most beach scoops, it’s still way too big to get in crevices between rocks.  Needs a pointy end instead of rounded.  I wish someone with better design capabilities could come up with something just for rocky creeks like this.  

Same exact scoop as I have!

I agree it should have a point to it, almost a trenching shovel end with fairly open top to be good in gravel.

Higher frequency means you have a wider gamut of detection on lower conductors (more spread on targets in that range). This crunches the mid and high conductors up high and making them more susceptible to iron wrapping. Other issue with high frequency machines is when you have rusty targets with halos they will respond to those too aggressively when the ground is wet which will smother other targets nearby. Using a dd coil will make that even worse as dd's tend to be very perpendicular in detection.

Big question is then is the NFD 90 chasing the nugget hunter market in mineralized soil as your comparing it to the Orx with HF coils OR are they pursuing the relic hunters looking for coin sized targets in iron infested grounds?

Prospecting machines can be used for relic hunting, I often use my Gold Racer for that but not around a 1700's barn or old cellar hole from a house that burned down and especially not after a soaking rain.

Not for nothing but I think there is a market for concentric coil machine at lower frequencies for iron infested grounds. Something the SMF trend seems to be skipping over as those machines seem to be more targeted towards beach hunting and general coin and jewelry hunting.

Good looking river there makes me want to dust off my fly rods 🙂

I bent the @#$% out of my first basket scoop on gravel like that, Not easy at all to fish targets out. Thought of using a mud shovel but not sure how well that would work either. Kind of need a half shovel half scoop for that kind of water hunting.

Nice gold, bet theres more stuff there. Congrats

I am curious about this machine still but hesitant as high frequency machines get slaughtered here when the ground is wet due to high iron content here in new england. When its dry I have no problems picking out targets with 56khz or even 40-45khz on d2 but start hunting near the wetlands or after a good rain the high frequencies tend to be too noisy. Tesoros I have at 14 khz and 17khz do very well and D2 I end up using mostly 13khz smf or mono.

Average for older coins tend to be in the 6-10" range but sometimes bit deeper here depending on area and previous activity.

Still wondering if your machine would do better in the 10khz range and concentric coil. That I think would make it a nice relic machine in this neck of the woods.