Manticore Puzzle

[FFX2]

FYI those ears are made the way they are so that they are flexible AND DON’T BREAK!! 

 

[PimentoUK]

The ears are long so that they can easily bend inwards when the bolt is tightened. The bending is spread over a longer length of material, not concentrated over a very short length, like on the Eqx coil ears.

Take a 12 inch plastic ruler. Fix one end, can the free end deflect two inches either way? Yes, easily, it's never going to break the ruler. Now take a 6 inch ruler, and deflect it 2 inches. It's straining the plastic more, and if you repeatedly bent it, you may get some cracking and failure.

I would've liked to see the carbon rod fit INSIDE the end-fitting, rather than the other way round. That would be a stronger solution.

[Sandheron]

Why are they not carbon fibre as well with a nylon threaded insert? 

[PSPR]

I thought that was the "receiving ears" of the detector.  If you break them it won't be able to hear the signals!  

[midalake]

48 minutes ago, FFX2 said:

FYI those ears are made the way they are so that they are flexible AND DON’T BREAK!! 

 

43 minutes ago, PimentoUK said:

The ears are long so that they can easily bend inwards when the bolt is tightened. The bending is spread over a longer length of material, not concentrated over a very short length, like on the Eqx coil ears.

"Flexibility" has NO bearing on breaking or not! This is really an equation of plastic compound and engineering forces, one which failed on the Equinox. 
Fractures occurred along the entire ear where it meets the coil, also through the coil bolt hole not affecting the base of the coil ears.   

[PSPR]

52 minutes ago, PSPR said:

I thought that was the "receiving ears" of the detector.  If you break them it won't be able to hear the signals!  

You guys are a humorless bunch.    Now that was funny!!  

[FFX2]

53 minutes ago, midalake said:

 

"Flexibility" has NO bearing on breaking or not! This is really an equation of plastic compound and engineering forces, one which failed on the Equinox. 
Fractures occurred along the entire ear where it meets the coil, also through the coil bolt hole not affecting the base of the coil ears.   

Actually flexibility does have bearing on breakage as does the radius molded into the corner for strength.

[midalake]

Just now, FFX2 said:

Actually flexibility does have bearing on breakage as does the radius molded into the corner for strength.

OK, we will disagree. 

[mn90403]

4 hours ago, strick said:

They made them long so they have more flex so the dummies that over tighten their coils wont break them as easily 🙂 But yea they look kinda long. That plastic is very flexible... to be seen how the set up lasts for prolonged water use. 

strick

In my experience with the Explorer coils and the CTX (which I broke many years ago) Strick is right.  They used that same coil 'design' on the Equinox, and it is faulty.  I lobbied on these forums many times to make the coil ears longer, but I see on the Manticore the 'ears' have been shifted to the shaft.  You now have a fork if I am seeing it correctly.

This will keep the integrity of the coil even if the ears/fork breaks.  A new 'fork' can be inserted in the bottom of the shaft, but it may be glued so strong that is not possible.  The coil has no ears now to break.

This fork may be a bit longer than needed but if made out of the right material it should not affect the swing of the coil or its balance.  Those of you who have them can tell.  I'm not on a list yet.

Going back to the old coil ears style, mine were too short and the tightening bolts with the big heads were actually torquing against the ears where they attached to the coil.  Sometimes you could not tighten the shaft in position so you would break the coil in the shape of the tightening bolt.  The cracked coil got a curve from the thumb screw right at the coil.

When this happened to me and my CTX 17 I had to grind off the remaining 'ears' and attach an external holder with tie straps and it still works.  At the time I researched a solution years ago I didn't even know you called the coil attachments ears.  If those ears would have been a bit longer, I am convinced they would not have broken and would have still been flexing on my 17" coil today.

As you can see, I'm a bit obsessed with this coil attachment problem and we'll have to wait and see if this new 'pinch system' from Minelab will stand up to time and detectorists.  

[FFX2]

1 hour ago, midalake said:

OK, we will disagree. 

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