Coil Ear Stiffener Recomendations?

[Badger-NH]

37 minutes ago, phrunt said:

I put wax on my skis and snowboard to make them more slippery, I put wax on my surfboard to make it less slippery. Defies logic but works ?

Come to think of it, wax and silicone are both petroleum products and are made from the same basic thing.

Surf wax has sticky stuff added to it. You wouldn't want to use it on your snowboard. Nor would you put ski wax on a surfboard.

 

[67GTA]

That's the same design I was looking at. Seems like it would help transfer a lot of the pressure back to the coil. Found out my local library has a 3d printer but they only use pla. It won't be as strong as abs. It's only 6 cents per gram so I am going to have them print one to try out. I can get one made from abs later if I decide to use it.

[GB_Amateur]

On 10/30/2020 at 8:53 AM, GB_Amateur said:

Pretty sure I have spare 'washers' for that so I'll try the silicone on one set.  If I don't like the result I can revert to the other set of washers.

Silicone lubricant arrived but first I made some measurements.  I noticed some differences on the ML rubber washers.  Here is what I measured (estimated single measurement uncertainty ~0.01 mm):

3 sets of the 'teardrop' shape for the Equinox:  Four of them were within 0.01 mm of 5.00 mm.  The other two were 5.07 mm.  The only set that has been used was of the smaller size.  There may have been a tiny bit of wear loss (0.01 to 0.02 mm) on one of the used washers.  (4.99 mm compared to 5.01 mm)

2 sets of the special (toothed on one side, flat on the other) washers for the X-Terra:  (Note:  I'm using the X-Terra lower two shaft sections on my Eqx to convert it to S-shaft).  The two used ones were thinner by about 0.15 mm!

So if my measurements are anywhere near correct, both manufacturing tolerance (Equinox washers) and usage wear (X-Terra washers in particular) come into play.

I've put the silicone spray lubricant on the X-Terra washers and installed the newer (thicker) ones on my shaft to accomodate the Equinox coil(s).  The fit so far is snug but I didn't have to force the coil ears over the washered shaft end.  I'll be going detecting tomorrow so I'll see how well the assembly grips -- i.e. how easy/difficult it is to change the coil angle.

 

[GB_Amateur]

On 11/2/2020 at 4:11 PM, GB_Amateur said:

I've put the silicone spray lubricant on the X-Terra washers and installed the newer (thicker) ones on my shaft to accomodate the Equinox coil(s).  The fit so far is snug but I didn't have to force the coil ears over the washered shaft end.  I'll be going detecting tomorrow so I'll see how well the assembly grips -- i.e. how easy/difficult it is to change the coil angle.

Worked like a charm so far.  In standard operating mode the coil angle is easy to change but doesn't do so without my intent.  When I lay the detector down it does flatten, but that doesn't bother me one bit.

[FloridaSon]

Quote

it does seem more of an issue for water hunters. 

...not in my case, beach hunt only but no surf, or in water. Took every precaution including detect-ed washers. I noticed the stock washers were so thin the shaft end rubbed on the ears. They would make the coil creak due to the plastic to plastic rubbing. Thought the thicker detect-ed washers would protect it. After it broke yesterday, when I disassembled the coil from the shaft I noticed grains of white sand between the washers and coil ear bearing surfaces which were scored. Maybe i should have been taking these apart and cleaning them. Don't think silicone and sand would help in my case. 

The white areas are wear. So spraying the bolt might help reduce scoring and scraping. The edges of the coil ear are white and may have been cracked before breaking.  Man this is all over the place! 

[Joe D.]

FS,

    We are not doing anything wrong with our coils! It's a poor design, and/or the poor choice of recipe for their thermoplastic! In a nutshell, the coil ears are too thin and brittle! I'd much rather have the tab's reversed, like the AQ Ltd.! Makes for a much beefier design option!??

[FloridaSon]

18 hours ago, Joe D. said:

FS,

    We are not doing anything wrong with our coils! It's a poor design, and/or the poor choice of recipe for their thermoplastic! In a nutshell, the coil ears are too thin and brittle! I'd much rather have the tab's reversed, like the AQ Ltd.! Makes for a much beefier design option!??

True, but 'they' are not going to fix it. My coil is enroute to ML for hopefully replacement. And I want to keep hunting, so I don't mind being proactive a little bit. You make all good points. regards

[FloridaSon]

On 11/2/2020 at 4:11 PM, GB_Amateur said:

So if my measurements are anywhere near correct, both manufacturing tolerance (Equinox washers) and usage wear (X-Terra washers in particular) come into play.

I can see wear between the washers - the whitish areas. Also across the break point. And look in the holes that accept the bolt. So may be a combination of things.

[Againstmywill]

2 hours ago, FloridaSon said:

I can see wear between the washers - the whitish areas. Also across the break point. And look in the holes that accept the bolt. So may be a combination of things.

From the looks of this, for the wear to be the cause of the breaking, the fracture would have to follow the arc that is scored in the plastic. It did not; it snapped perpendicular to the possible weak spots. While there is stress that causes the failure, it seems likely that it has more to do with the composition of the plastic, IMHO.