Beach Hunters And Carbon Fibre Rods

[Erik Oostra]

Beach hunters might’ve heard the mighty uproar over at the prospecting side of the forum.. They’ve got their undies all knotted up over their high frequency VLF detectors reacting to carbon rods.. As if they’re the only ones.. Whilst Geotech’s excellent video shows that carbon rods don’t react when the detector is in multi-frequency beach mode (where the rod’s signal is filtered out just like a salt signal), not all beach detectorists hunt exclusively in beach mode.. Nor do they just hunt on beaches.. I for one also hunt gold, silver coins and the occasional bit of ‘old junk’ (relics)..

I don’t buy any manufacture’s claim that reactive carbon rods only effects a small, easily disgruntled, part of the metal detecting community.. Prospectors are not the only ones who demand the best performance from their tools.. When I read about this ‘problem’ I straight away started to think about ways to fix it.. Even if there's only a slight chance that a carbon rod is gonna make me miss a gold ring (or anything else!), then to hell with it..

To this end, I’ve put the original lower plastic rod back on my Nox 800 (with a carbon fibre upper rod) to serve as my general purpose detector, whilst the fully carbon fibre Nox 600 stays in beach mode as a beach detector until I can get another plastic lower rod for it.. Just like every other detectorist, I don’t want anything to screw up my chances of finding my favourite bit of metal.. 

[Tin Can]

Carbon rods sound off on the Deus 2 in beach modes "machine wide open" i can only presume other machines will if you open them right up, however the carbon fused stem made by XP isn't effected,

I brought this to light back in December 2023, from my test you will only ever have an issue when diving "tapping the coil on the sea/river bed to straighten it up.   

[midalake]

2 hours ago, Erik Oostra said:

I don’t buy any manufacture’s claim that reactive carbon rods only effects a small, easily disgruntled, part of the metal detecting community.

Carbon fiber rods at a Salt Beach/water have ZERO effect on anything.

Have been using carbon fiber for over 20 years when no one even knew what it was.  Also have used this style rod on at least 5 different detectors. 

[Skull diver]

I have no way to create a mold right now and it will probably be a job to be done within two weeks.

Certainly, with all the coils I can't go more than 20 points without encountering false signal, and in spite of what it sounds like, the rod might instead have some weight, because only moving the detector really slowly will reduce the effect.

I am not contradicting @midalake or confirming without first testing with a plastic rod end... We shall see

[TampaBayBrad]

38 minutes ago, Skull diver said:

I have no way to create a mold right now

If you're really that curious, why not just detach the coil from the shaft and hold it in your hand and sweep a bit next dive. Use it for a few yards until you can tell if there is any falsing difference than when it's attached. (Don't wear a wrist watch that arm!)

[Skull diver]

5 minutes ago, TampaBayBrad said:

If you're really that curious, why not just detach the coil from the shaft and hold it in your hand and sweep a bit next dive. Use it for a few yards until you can tell if there is any falsing difference than when it's attached. (Don't wear a wrist watch that arm!)

This is a very good idea and will probably also be the quickest way to find out.
Although with three coils available I would need two more rods to change them frequently.

[Erik Oostra]

4 hours ago, midalake said:

Carbon fiber rods at a Salt Beach/water have ZERO effect on anything.

Yes, Geotech's video in another thread about carbon rods shows this clearly.. The rods don’t react when the detector is in multi-frequency beach mode (where the rod’s signal is filtered out just like a salt signal).. I'm thinking about times when I'm not using my detectors in beach mode..

For me it's a bit like noticing a weird engine noise when I'm driving along.. It could be nothing and have zero effect on the car's performance, but my mind won't rest easy until the noise is gone.. I know that's probably irrational and I agree that for many years no one realized there even was a problem.. But now the problem has been brought to our attention, I can't stop hearing the weird engine noise.. And for simple peace of mind I'll fix the problem even though it might not be a problem at all.. 

I don't need additional background noise when detecting, where I'm constantly second guessing myself wondering if that iffy signal is the rod or a juicy bit of gold.. Just like everyone else I like to squeeze the most out of my detectors, and this means that from now on I'm using plastic lower rods even in salt water.. Maybe an overkill but also peace of mind..  

[Steve Herschbach]

13 hours ago, Erik Oostra said:

I don’t buy any manufacture’s claim that reactive carbon rods only effects a small, easily disgruntled, part of the metal detecting community.

I and quite a few others on the referenced thread do not either. Non-conductive lower rods have been a near absolute (there are exceptions, CTX for instance) industry standard for decades. Why? Because a conductive lower rod might cause issues. Not will, might. The simple answer for companies like White’s to make sure it could not be an issue was to use fiberglass lower rods on all their models, as White’s did for ages. It never had to be thought about or engineered around because the problem could not exist.

I do not have any issue with anyone making an informed decision to use an aftermarket rod that is conductive. It will not affect most lower frequency applications, beach modes in particular which tend to knock out the salt range. Informed decision being the key. What I do think is not wise is for manufacturers to use anything but non-conductive as a general standard. It’s just a common sense solution to keep accidents from happening. I’m sure Minelab simply overlooked the possibility of an issue when they switched from non-conductive lower rods on the Equinox 600/800 to conductive lower rods on the 700/900 and Manticore. For most people it will be a non-issue but for anyone running Gold Mode in particular it’s going to bite you. But it can show up in any mode that has a 20 kHz or higher frequency as a component, either singly or in multi. Easiest way to tell is just lay the coil back flat against the rod and wiggle it. You’ll know fast if there is a problem.

There are quite a few people who obviously are very defensive over all this and react poorly when it is brought up at all, insisting it can’t be real or a problem. Check it out and decide for yourself instead of listening to anyone, including me. The idea is for people to have information to make their own informed decisions. You know, learn something - knowledge is power. Simply knowing what this is and why it occurs can help alleviate or avoid the issue entirely, as long as you are expecting it. Not everyone who owns these models will use them exclusively in Beach Mode. And that’s where Minelab erred in my opinion. The standard rod should be perfect for all modes and applications, not just most of them.

 

[phrunt]

2 hours ago, Erik Oostra said:

Yes, Geotech's video in another thread about carbon rods shows this clearly.. The rods don’t react when the detector is in multi-frequency beach mode (where the rod’s signal is filtered out just like a salt signal).. I'm thinking about times when I'm not using my detectors in beach mode..

While that's true with the Equinox, it's not with the Manticore, the shaft reacts reasonably badly in Beach low conductor and Beach deep.  What this tells me is someone that looks for small gold jewellery on beaches has a lot more hope finding it with the Manticore, and that's a great thing, the Manticore no doubt in my mind is quite a big improvement over the Equinox as a beach hunting machine after seeing how much more it picks up a carbon shaft than the Equinox in some of its beach modes, it's been said a few times the Manticore was intentionally designed around being a machine for this task, and it does seem that's the case, although in all their testing they must have missed something as the firmware update included this, "General Stability Enhancements: Including improvements to Beach Mode Ground balance on dry sand"  

The Equinox in general doesn't react near as badly as the Manticore does on the shaft, in any situation, demonstrating the extra horsepower the Manticore has.

I'm a lot like you Erik and your car noise analogy really suits my way of thinking, stuff can drive me mad and I can't let it go until it's fixed 😛  I've been known to pull many all nighters tackling tasks as I can't let them go until resolved, no point going to bed as I won't sleep until it's fixed! 

The best thing about this whole shaft debacle is I'm more impressed by my Manticore than ever, seeing it's differences over the Equinox, it's not just another mildly modified Equinox like the 900 is, it's a new animal, different enough to be a new detector, not something that could have been done with a firmware update to the 800 like the 900's software changes.