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Jonathan Porter

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  1. The flat wound coils on the 5000’s do the same thing. I just had a GPX17 returned because the customer swore the coil was NOT sensing targets at the 10 to 11 O’clock position!! 🤔 🤪 (physically impossible but I was forced to go and test it any way and sure enough perfect), looking at the coil I could clearly see scrape marks in the plastic where the scoop had been passing through that zone along the direction of the windings rather than across them. If you look at the 6000 coils from above you can see an indent line in from the edge, that’s the width of the windings, in essence they are semi flat wound and as such the target needs to traverse that whole section (from edge to the white line) to be sensed by the coil, scoops are generally angled on the bottom so as you move your elbow away from your body to scrape the scoop over the winding the angle will change ever so slightly relative to the position of the target in the scoop. If possible you should always run the target at direct right angles to the windings not along the windings to let the coil see the whole target relative to movement etc. I always give the scoop as vigorous shake back and forth and pass over the coil again on scoop with no target signal just to be sure. Also make sure your coil is a flat as possible relative to the earths field when you’re retrieving a target, any sort of angle lets in EMI and that will drown the small targets by a huge amount. Not saying this is the reason behind the above comments just my observations using the incredibly ultra sensitive GPX6000. JP
  2. The ML 6000 coils are built totally differently so should have much better longevity
  3. It all depends on the construction method. If the shielding is paper then that can move around and eventually become chaffed through micro movement. Traditional ML monoloop vaccume formed foam sandwich style coils used on the GPX5000 are a good example, the shield paper top and bottom between the plastics and the foam holding the windings will rub and eventually the shielding will fail. I'm not sure if this method is currently used on any GPZ coils but it has been one of the main reason for coils becoming noisy in the past. JP
  4. That’s the potential pitfall with second hand coils now coming onto the market, people who have no knowledge in the subject are buying used coils with adapters and have no background idea of the risks associated with constantly extending the shafts and also the very big risks if the adapter is a home made one that has not been made properly. I’m now seeing a lot of well used GPZ7000 mid shafts coming out well past the lock point on the upper cam lock essentially extending the shaft length by 1 to 2 inches (locating lock tab on the mid shaft pulls past the first cam lock tab (there are two silver pins)), that extra few inches will definitely put a lot of stress on an adapter that has been well used previously on a unworn GPZ. I’m now seeing a lot of X coils coming up for sale on FB pages since supply has been cut off due to the war and the release of the GPX6000, some coils can start to wear out internally through constant use, especially things like shielding etc, internal wear is not a major issue other than elevated noise like touch sensitivity ect but incorrectly made adapters could be catastrophic especially if the mid shaft is worn. JP
  5. I have often dug rusty pieces of steel and knew it was steel well before I actually got to the target because of the rust staining spread out in a ‘Halo’ around the target. Remove the halo, place the actual target back at the original depth and orientation in the same hole and no target anymore. Another example is of a number of coins buried by an associate in a test bed in mineralised soils over 30 years ago and how gradually over time all those targets became discernible by detectors when originally they were well past the edge of detection. Yes it is theory and not fully understood but there is plentyof anecdotal evidence to suggest that Halo’s exist 😇, exactly how that works I’m not sure but ground definitely has a chemistry that can alter over time. One example is supergene gold in laterites (most gold wash layers are a form of laterisation where ground water moves through the soils on into the bedrock till it hits the water table, by then a lot of minerals are in solution (especially iron) only to be percolated back up into the wash layer), studies have shown pieces of gold formed in laterite can have a trail or halo of micro gold migrating in towards the seed nugget which has grown over time, I have found a few of these over the years especially around Sandstone in West Australia. If it also a common thing to follow a reef from the surface from rich specimens laying over the stump of the reef that when found produce reasonably good grades of gold (but not big like the surface gold was) then have it turn into a massive enrichment right on the water table only to dissipate away into sulphides or low grade ore as you go deeper. I’m pretty certain most nugget patches are old water table gold enrichments that have weathered out into the environment with the nuggety gold coming from adjacent iron rich country rock in close proximity to the gold bearing reefs. This would go a long way to explaining why the nuggets often tend to be in the upper gravel layers and do not continue to depth even though the wash layer is still going down (particularly obvious phenomenon in flatter country where gold has weathered from colluvial/elluvial deposits like we have here in Australia). Once again just my 2cents, I am enjoying this discussion. JP
  6. I have dug many many nuggets in goldfields where the actual purity of said gold is in the 82% range with the other metal predominately silver and copper. Those nuggets have presented as looking very good purity until the thin surface layer has been scratched or rubbed during digging then you see the actual lower purity metal beneath, in essence those nuggets have had a reverse gold plating technique applied to them where the oxidisable metals have weathered out leaving a purer layer of gold microns thick on the surface (this is also one of the reasons why I’m skeptical of purity tests done on nuggets with an XRF, ingots are OK) . A lot of Australian gold is in the 90% range due to enrichment, the process where metals such as copper and silver are leached out over time through mobilisation ect (gold going into and out of solution in the oxidised layers). Halo effect is VERY probable and acknowledged by metal detector developers who I associate with, when a nugget has been in-situ for a very long time any oxidisable metals such as silver and copper can weather out into the surrounding soils over time. This halo then presents to the detector a much larger target than the actual original seed nugget and goes a long way to explaining why a nugget can be sensed at far greater depths that an in air test can achieve. Ground chemistry can also have a part to play especially when the ground is disturbed (this is really evident in push and detect operations where the freshly opened ground is extremely noisy and variable compared to undisturbed ground or dozed ground that has been left open for a period of time (especially if it has rained then dried out)). Ground is a lot more complex than most people realise and has a big impact on metal detector behaviour and also oxidisation of nuggets etc, a good example is the coating of iron oxide you often see on nuggets dug from oxidised tertiary gravels etc, conversely you often see nuggets coming from the ground that look bright and polished, that is from the acidic nature of the soils they came from. Just my 2 cents JP
  7. Beats my biggest bits by a whopping 16 and 20 ounces ounces Reg, I too live in hope that my bigger one is still out there somewhere. 😝 Maybe I need to find some cursed ground to work in? 🤔 Shouldn’t be too hard to do in Victoria, they’re closing more and more of it every day. 😞
  8. Got up early as usual, got my morning coffee sorted, sat down and made myself comfortable then tuned into my favourite forum for my daily ‘Miners journal’ fix only to find there are no new entries. 😢 Have been throughly enjoying reading these posts every day, a window into a bygone era that is very hard to put down once started. Might have to go back and read yesterdays entries all over again or I’ll go mad!! 😆 JP
  9. I am absolutely useless in trashy areas unless there is depth to the ground and enough space between the junk targets to get a swing in, I’m pretty good at pulling deep targets in those scenarios assuming the deeper sections are undisturbed. If the ratio of trash to good targets gets too high on the deeper stuff then I shoulder arms and get “The Hell out of there” for less trashier sites. There is still a lot of good gold to be had for the brave souls in amongst the trash, there is also a lot of insanity too. 😝
  10. The key to the GM is simplicity and if you’re not driving the thing too hard sensitivity wise they run very quiet thanks to zero threshold. I personally prefer the EQ800 because I have more control and the discrimination is excellent especially with the 6” coil, just wish the coils weren’t webbed, they are a pain on a gold machine. The 24K sounds very interesting I have a lot of fond memories of my Whites VSat, but alas I’ve since been severely infected with PI snobbery. 😂
  11. Monster sells really well here Simon, I think right now it is the most popular volume selling VLF on the market world wide. The key is its simplicity for new chums.
  12. Don’t think it’s about forcing you to buy into a new one but more to do with developing tools for the end user to upgrade which requires a lot of R&D dollars etc, when you consider the vast majority of Monsters end up in Africa where there are largely no computers or even service centres it ends up in the not viable basket. Just my opinion of course I really have no idea behind the real resistance but would say its down to resources on a mass selling extremely simple product into markets where the upgrade would never be used anyway. But I will say this, the new forced GB feature transforms the Monsters usability, the auto GB is really good over the ground but the second you lift it away it goes out then takes ages to get back again, in most cases I would just power cycle and let the forced GB at start up deal with the problem rather than pumping endlessly waiting for it to get its act together. It is also very handy to force a GB on a suspect hot rock, giving you more info to help make an educated guess. The GB on the Garrett 24K sounds interesting especially here in Australia where even our quiet ground can be quite variable.
  13. Simon does your GM1000 have the forced GB feature via holding in the disc on off? I pushed for this right from the start, it was introduced in later machines with no fan fair. An absolute must in an auto GB only machine.
  14. In a lot of cases the simple truth is that’s all that’s left. Hurts to realise that but some patches have been pounded so much they need a GPX6000 to bring them to life again or you have to move on to fresher fields and hope for the best. Finding even a tiny crumb is far better than nothing at all especially if you only have limited time or are constrained by a goldfield that has seen a lot of action over the years, I for one would go detecting for a fix on the most flogged ground imaginable if that was my only choice, having a chance to ping even a tiny crumbs is better than not going at all or coming home empty handed. The 6000 will be in vogue for years to come because those tiny pieces are so plentiful even on flogged ground, I can’t imagine what the sensitivity will be like when we get our hands on a 10” elliptical or some such, a PI with VLF like sensitivity, mind boggling. 😳 JP
  15. The GPZ 7000 sells really well in Africa, the 6000 is a PI so its GPX monicker is relevant. Other than coil choice the 6000 punches just as deep as the 5000 on large gold, when more coils come online (thanks to Coiltek) then coil choice will no longer be an issue. IMO Minelab have marketed for the smaller more plentiful gold finding ability of the GPX6000 because that is where it is excels with a very clear advantage, for larger deeper gold we have the GPZ7000, most places having already been pounded for years by the GPX5000’s etc with all sorts of coil types and sizes. The GPX6000 is not a toy but a fully fledged serious gold finder designed for all sorts of terrain, green fields ground or pounded flogged out areas. The coils provide for the GPX6000 tell the real story, GPX11 Mono for general purpose detecting with crazy sensitivity and very good depth, the GPX17 Mono for patch hunting also with crazy sensitivity for small pieces and good depth and the GPX14 DD for nasty areas with high EMI or salt ground. JP
  16. All the Hipstick’s we manufacture here now are actually printed around the D rings, with the original 3D printed versions developed by Chris Porter the ring was first split then forced through the printed head part after printing. In hot weather or in hilly terrain where sideway’s forces occur the D ring could be forced open and come away from the head. I not only use a Hipstick to control the weight of the detector (including the 6000) but also use them to help control and maintain smooth movement of the coil. It takes a while to learn how to swing when first using them but once learned they are invaluable for coil control. I can swing a 7000 without a bungee for about an hour but then all the connective tissue and ligaments around the elbow area and shoulders start to burn and ache, it’s nothing to do with strength but more to do with the need for those parts of your body to finely control the coil without hitting the ground, the better the control the better the gold find outcomes. Life without a Hipstick is just a recipe for a lot of unnecessary pain and potential long term injury. At The Outback Prospector we supply a free Hipstick with every GPZ 7000 we sell, including used ones. Buyers should also be wary of cheap counterfeit copies being flogged off on eBay and unscrupulous dealers etc. 😡 JP
  17. Hi Rob, fire us a contact form via our web site (just use the detector hire link). You’ll get a closed for Christmas break email back but we can then get onto this once we are back in the office. My wife manages all the business emails etc so this is the best way to streamline things, I get yelled at if I verbal anything to her 😂 https://outbackprospector.com.au/contact-us/ JP
  18. Hey Rob, my son Timothy has taken on the Australian manufacturing of them here through our OBP store. Haven’t spoken with Chris in a while but would have no issue in helping out our mates across the pond. Store is closed for the summer holidays but will be back on deck again in a few weeks time on the 17th.
  19. Not at all, mine is tongue in cheek also. 🙃😁
  20. It’s a lot like reading FB and other online dross, sometimes you’ve just gotta dig through all the ‘lead shot’ posts to get to the gold nuggets.😬 😊 With the 6000 I can literally ping a nugget any time I want, it’s that good! So good in fact I actually don’t feel challenged by it, sounds arrogant I know but I really am spoilt for choice when it comes to finding gold, so the 6000 waits patiently for when I get into a gold slump and desperately need a fix to get me back on the straight and narrow. I have one of those scenarios in play right now so the 6K battery will be getting charged up over the xmas break so I can finish the year off with a flourish and maybe even harken in the new year with some fireworks action of my own, no alchemy involved just pure science. 😊 JP
  21. I think Simon has done a brilliant job of this thread, he’s written his POV and it has polarised some pure gold in the form of conversation and interaction, I for one thank him for having the courage to express his opinion in a visually enjoyable way. 😊 Many years ago a person who I respect told me that ‘opinions are like backsides, everyone’s got one’ 😝 (guess who? Hint his name starts with S 😊), so long as those opinions are not expressed in a way to cause another harm then you have a right to them including expressing them. Back to volume, Steves method IMHumbleO is best used with elevated Gain/sensitivity, you can kind of do this with the 6000 by using Auto+ in the hopes that the ground conditions will allow the auto sensitivity to rise above the pre-set level of the manual mode, the best way to confirm this is to listen to the variation of the threshold, if its gets a jitter going in auto+ mode then that suggest there is a bit more EMI flutter that becomes evident with elevated sensitivity. DO NOT be afraid to use the Manual control with the volume method described by Steve, I find I can run a lot more Manual sensitivity control with the volumes down. The other thing I have found is the BT volume of the standard headphones is pretty powerful so I tend to set them half way (push the - button until the volume is at it lowest level then slowly push the + button till it reaches its highest setting then divide by 2 (10 from memory)). The 6000 has a very dominant threshold so I recommend you set the volumes with the coil held flat in air as movement signal variation adds to the base threshold position. As Steve has said so long as you can hear the threshold you are good to go and you will be amazed how low you can run the volume before it starts to impact on threshold volume. I actually prefer to use the standard headphones direct wired so there is only one volume control, I do not like the way BT compresses the audio. The advantage of the lower volume is it smoothes out all the dross in the base threshold, all the imperfections that are not target related, the 6000 is a very nervous twitchy hyper sensitive detector and you need to train your brain to ignore a lot of the variability, when I see complaints about EMI this usually suggests poor coil control and too much volume being used as a sensitivity control which is back to front for good detecting. The above methods I’ve described are slightly different to what I’ve been playing with on the 7000 branching out from what Steve has touched on but in principle it all ties in extremely nicely when you think about it logically, where I was coming unstuck was not being prepared to increase Gain/Sensitivity on the 7000 sticking to more conservative operations and not taking advantage of the ‘pop through’ that Steves method achieves with high sensitivity, with low volume being the key. Once I combined the insane sensitivity with much lower volumes everything just fell into place. Once again thanks to Simon for creating this thread it has galvanised some good discourse on the subject of metal detecting and I hope he can forgive with all the drifting away from topic....
  22. Flak your opinion has merit in my eyes, thanks for the heads up. 😊 JP
  23. Steve, that’s the beauty of this forum, it allows for polarised views and also provides the opportunity for people to become enlightened and then change their POV, me very much included. 😊 As an example I’ve this past season taken on board your comments about running your machine flat out, something I have always discounted as nigh on crazy, because of that walleyed view I was missing a vital piece of information that you’d provided with your insane settings suggestions....... do you know what that is/was? Volume!! 🥴 I totally missed that you run your volume low. Well what a turn around that has been for some of my approaches to certain aspects of my detecting when the conditions allow for it, of course I’ve tweaked the concept to suit my particular tastes but the whole thing has coalesced out of your personal approach to detecting and willingness to share your ideas, so thanks mate. 😊 JP
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