Manticore Puzzle

[midalake]

50 minutes ago, FFX2 said:

Yea I work designing and building injection molds so I obviously know a lot more about it.

Maybe you need to work for Minelab? If coil ears are 2.5 inches long and the shear strength of the plastic is 25psi. Compared to coil ears 3.5 inches long with a shear strength of 25psi>>>Which one breaks first? 

[phrunt]

The lower shaft becomes the sacrificial lamb this time rather than the coil, cheaper to replace for them under warranty and cheaper for us to replace outside of warranty.  I'm fine with this change. 

If they become a problem the aftermarket will come up with stronger lower shafts, perhaps thicker or somehow reinforced ears on the shaft if that helps. 

I've never understood why many VLF detectors designers insist on such thin ears.  They could take a hint of earlier model GPX coils or even the GPZ coils, their ears are rarely an issue if at all, I don't think I've ever seen anyone break ears on them.

Coils like this 25" DDX NF coil weigh 1650g, yet you never hear of anyone breaking the ears on them or any of the older model GPX coils.  I doubt users of them are anymore careful than Nox users with leaning on the coil getting up or bashing it around.   They have to be done up tight too, to stop such big heavy coils flapping in the wind.

[PimentoUK]

"Also the coil cable is very thin at 2mm thinner than the superbly armored Nokta Simplex coil lead"

I assume the Simplex has a conventional coil, and coil cable. Meaning no electronic amplifier inside the coil. So it uses screened cable for the Receive coil wires, screened cable for the Transmit coil wires, and possibly another single wire for an electrostatic shield connection, maybe followed by an overall shield, then the outer sheath. That makes for a fat cable.

The Equinox ( and I assume the Mandingo ) have a pre-amplifier in the coil, with a differential output. So the RX cable doesn't really need shielding. There are additional wires, for a power supply, and a serial data link, but these can all be thin. The net result is the Eqx / Mandingo has a thinner cable.

[dsb]

The coil ears are yet to be thrashed by the weed wacker and crutch types, there's no hope.🙃

[phrunt]

I imagine they've tested the new ears well after the massive flop that was the Equinox ears, lets face it it's pretty easy to test a product for quality.  They just have to get a bit rough with it.

Look at these tests for Mars coils to get an idea how to test a coil. owners of Mars coils including myself have no fear of breaking our ears. 🙂 WARNING:  DO NOT try this at home with a Minelab coil, it will instantly combust.

[Joe D.]

  I don't think that's ML's engineering team!!😂 Looks like the type off "testing" my son used to do with some of my tools, when he was young!!🤣👍👍

[Carolina]

I’ve always wondered why polycarbonate plastic (LEXAN) has not been used in an instance such as this? That stuffs tough !!!

[phrunt]

1 hour ago, Joe D. said:

  I don't think that's ML's engineering team!!😂 Looks like the type off "testing" my son used to do with some of my tools, when he was young!!🤣👍👍

That's the thing, your son didn't care if he damaged the tools so he tested them properly. 

Either way, Minelab's coil ear testing engineer is a very busy man.

 

[Valens Legacy]

Those long skinny ears are for the water wings so you don't lose the detector in deep water.

The wings will also wipe away your marks when beach hunting to confuse other people on where you were.

[PimentoUK]

"I’ve always wondered why polycarbonate plastic (LEXAN) has not been used in an instance such as this? That stuffs tough !!!"

The Eqx coil is moulded from a Polycarbonate ( PC ) & ABS blend. My hunch is they used an inappropriate blend - too much PC , or not enough PC.
Plastic failure is not my area of expertise, but I recall stress-cracking to be a characteristic of PC, so if anything, I would speculate using less PC in the blend would be better.