Waterproofing a Hole in Plastic Casing
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AlanCranston
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Waterproofing a Hole in Plastic Casing

by AlanCranston » Wed Nov 27, 2019 5:58 pm

Hello, this is a very specific and minor question, but I have not found an answer by searching on product. I have an outdoor light fitting which started life being waterproof, but is now not. It is a suspended plastic fitting, bit like a flying saucer. Quite large for a light fitting, maybe small for a flying saucer. It is suspended by three thin wires very like bicycle brake cable which go through the plastic on the top of the fitting, with a nipple on the end of each to secure and some sort of sealant over the hole in the plastic. The problem is that, through swaying in the wind, the sealant has broken and the hole enlarged slightly, so rainwater leaks in. I've tried to repair with silicone but (slightly to my surprise) that's lasted no time at all. It's likely the swaying of the fitting is an issue as well as the wrong material.
So what material might I use?
Or else, is there an alternate solution. Something like a mini eyebolt and appropriate grommets/washers. I've not been able to find anything ie, nothing seems appropriate to the less than 1mm diameter of the wires.

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