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Comment by dsfyu404ed | Hacker News Reader

Cable lacing is used in aerospace because it's lighter and they use such generous safety margins for preventing abrasion and securing wires that the issues with the cable cutting the insulation or abrasion that make loom the obvious choice are non-issues and aircraft, it's easier to inspect cables that are laces (vs ones in a loom) and spending a few grand to save a few pounds is justifiable in that context.

Temperature/environmental concerns are basically irrelevant because loom can be made out of the same or similar materials as the wire insulation. I know I've seen braided loom in small aircraft. I can't remember where though.

Cable lacing is usually the right tool for aerospace. It is not the solution to every problem like the internet thinks it is.

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This is why I'm glad I shared this article, because it's the one thing on HN I'm qualified to give an opinion on - making harnesses is my job! The wire insulation is an extruded polymer, not a heat shrink, so we can't use the same material as nice as that would be.

We had an issue with Airbus a few months ago where their own approved heat-shrink actually failed the flammability new testing (it smokes profusely...) We can now only use it in 50mm increments for protecting wire bundles from potential high abrasion sections (around connecters, through holes, grommets etc.) The weight aspect has never been discussed. It's so insubstantial that it's not even accounted for on our units. Occasionally we'll use shielded round-it for high voltage cables to prevent arcing, or sensitive data cables to prevent noise, but below that round-it is still wire and lacing cord. It's simply the most practical assembly method. The same applies to freighter ship looms too; lacing is not just relevant the aerospace industry!

Installation in buildings. Try pulling a bundle of CAT6 cables from a comms closet with huge plastic blocks from zipties jutting out every other foot through 10-50 feet of drywall and/or drop ceiling. Loom doesn't even warrant a sarcastic comment in that context. The biggest advantage is of course the string takes the brunt of the stretch stress.

I'm not gonna go lace up a DC but it's still useful enough that every hardware store around carries rolls of twine right next to the cable spools and zip ties.

Industrial use - zip ties inside a control cabinet are incredibly rare if you ignore the tiny zip ties used to fix cable name plates. Slotted cable ducts everywhere. Transition to outside world using control cable, bundling stuff is rare, if necessary, it'll be a wire loom, cables being loose in the loom, no zip ties. It's way more common in machines to have a cable duct go to an energy chain which fixes each cable individually in every segment.

Lacing looks cool but in 99 % of applications bundling cables is not just not necessary, but would be counterproductive.

Also PVC cable jackets especially for industrial cabling have come quite a long way since the 60s in terms of mechanical, chemical and UV resistance. The PVC sheath of an industrial cable is a couple cuts above the material used in the H03VV of the average desk lamp.

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