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Old 08-04-2018, 08:23 PM   #1
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LifeSling box

I installed a fiberglass LifeSling box on the back swim step a couple years ago to replace the rotting vinyl bag. It has been great. However, today as I went for a swim off the swim step (I even got in twice!) I noticed that the retaining strap that holds the lid on had come detached.

The nylon strap is riveted to the sides of the box and then snaps at the top. A simple and effective system. However, the two rivets on the port side disintegrated because of rust. It appears they didnít use SS rivets. The rivets on the starboard side are ready to go as well. Iím pretty disappointed that something designed for use in the Marine environment would have such a simple but obvious flaw.

Iíll replace them with SS rivets when I have a chance.
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Old 08-04-2018, 11:34 PM   #2
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Be careful with stainless pops in fiberglass. It may be best to use a washer on the pin side of the rivet adjacent to the fiberglass. It will prevent the rivet from pulling through the fiberglass or cracking it. It may be better to use aluminum pops with a large head as well as a washer to spread out the stress of the rivet on the fiberglass surface. If it's not in contact with another metal, the aluminum will last. Use aluminum mandrel pops. Mixing aluminum pops with stainless or vice-versa will almost always result in electrolytic corrosion.
If you want to rivet aluminum but need higher fastener strength than an aluminum pop provides, use monel pops. They will hold up far better in aluminum than stainless. Actually, the stainless pops hold up, it just creates electrolytic corrosion of the aluminum being fastened. The monel doesn't.
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Old 08-05-2018, 02:36 AM   #3
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My seven-year-old lifesling plastic box is still at work.
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Old 08-05-2018, 05:30 AM   #4
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Can you use another, less complicated fastener? Small bolt, nut, washer, and lock washer or a screw into a sturdy backing?
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Old 08-06-2018, 10:25 PM   #5
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Quote:
Originally Posted by GregBrannon View Post
Can you use another, less complicated fastener? Small bolt, nut, washer, and lock washer or a screw into a sturdy backing?

Yes, I could. I just need to be sure that the inside is smooth so as not to hinder deploying the Lifesling.

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Be careful with stainless pops in fiberglass. It may be best to use a washer on the pin side of the rivet adjacent to the fiberglass. It will prevent the rivet from pulling through the fiberglass or cracking it. It may be better to use aluminum pops with a large head as well as a washer to spread out the stress of the rivet on the fiberglass surface. If it's not in contact with another metal, the aluminum will last. Use aluminum mandrel pops. Mixing aluminum pops with stainless or vice-versa will almost always result in electrolytic corrosion.
If you want to rivet aluminum but need higher fastener strength than an aluminum pop provides, use monel pops. They will hold up far better in aluminum than stainless. Actually, the stainless pops hold up, it just creates electrolytic corrosion of the aluminum being fastened. The monel doesn't.

Thanks Maerin, I wouldnít have thought about SS rivet damaging the box, but it makes sense. Aluminum would work find as there is no other metal involved. This application requires very little actual strength.
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Old 08-11-2018, 07:51 PM   #6
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Acorn nuts can also be used to effectively provide a smooth cover for the machine screw screw end.
Apply a wee bit of BLUE loctite so it stays put.

I have also used HDPE pieces, Starboard, as a nut for a screw, wood or tapping.
Smooth the HDPE edges and corners nicely, drill a definitely undersized pilot hole for the screw and drive the screw. The HDPE is tough, and if the pilot is drilled to grip the screw shank/shaft and not just the threads I've found it will not let go,
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Old 08-11-2018, 08:23 PM   #7
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Acorn nuts can also be used to effectively provide a smooth cover for the machine screw screw end.
Apply a wee bit of BLUE loctite so it stays put.

I have also used HDPE pieces, Starboard, as a nut for a screw, wood or tapping.
Smooth the HDPE edges and corners nicely, drill a definitely undersized pilot hole for the screw and drive the screw. The HDPE is tough, and if the pilot is drilled to grip the screw shank/shaft and not just the threads I've found it will not let go,

Great suggestions. Acorn nuts are an obvious solution. Again, one that I would never have come up with.

I have yet to work with starboard but I have a bunch of projects that I keep thinking about...
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