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Comment by hilbert42 | Hacker News Reader

I cannot understand why silicone rubber is not more commonly available for cable insulation. It is so much better than much of the badly plasticized PVC and other plastics that are now used.

What's made this situation worse is that it seems that worry over plasticizers and health etc. has lead to a reduction in the amount being used in cables. I have some power extenstion cables whose jackets have gone so hard that I can no longer coil them effectively — even though I take care the coiled cable still ends up a tangled mess.

Even if silicone jacketing is more expensive it's so good I'd pay extra. Trouble is it's not normally available on products found at the local hardware shop.

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> I cannot understand why silicone rubber is not more commonly available for cable insulation

Silicone is more flexible and high-temperature resistant, but it does have a major downside of being very easy to cut and strip. That's not great either, especially for power applications where short circuits are a concern.

Silicone also kinda sucks for crimping. Most crimps have one set of tabs which grab the conductor (which is fine) and then another set which grab the insulation, but in the case of silicone the insulation set tend to just slice the insulation and don't mechanically grab it.

I bought silicon 2-line cable to replace plastic insulated cable that came with my trafo-soldering-iron originally about 30 years ago. And how easy it is to cut, is what surprised me. It's still a good tradeof for this use case because dents in the plastic from accidentally touching the original cable with hot soldering loop were getting a little scary.

Unless you're running cables inside an oven just buy SOOW aka EPDM cables. They are the recognized standard for flexible, rugged cable assemblies resistant to just about everything. Silicone rubber is only used in very special cases because it's not as UV resistant or mechanically resilient.

Sorry, not available where I am, nor do I see USB, coaxial cables etc. of that type.

> SOOW aka EPDM cables

AFAIK there's nothing about the SOOW spec that requires EPDM.

> I cannot understand why silicone rubber is not more commonly available for cable insulation. It is so much better than much of the badly plasticized PVC and other plastics that are now used.

PVC, XLPE, and rubber insulation is more durable than silicone. THHN uses PVC, XHHW uses XLPE, SOOW cord uses EPDM rubber.

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