Pot metal - was something else
The Natural Philosopher <[email protected]>
| Newsgroups | comp.os.linux.misc,comp.sys.raspberry-pi |
|---|---|
| Organization | A little, after lunch |
| Message-ID | <[email protected]> |
On 09/08/2026 01:47, c186282 wrote: > The alloy does not seem very resistant to vibration. > It's soft enough you'd THINK it would be, but its not. > The problem is mainly that its has no fixed composition, Its random non ferrous scarp mainly. Use a magnet to get the iron and steel and melt what is left over perhaps > Most aluminum alloys and 300 series stainless are > not super-good with vibrations either - though > better than 'pot metal'. I've seen 'magnesium' tire > rims crack too. > Pot metal is heavy and brittle in my experience. Came across it back in the day in toys, carburettor castings, thermostat housings..valve covers..all stuff that needed shape retention but no great strength > Only steel - esp nearly pure iron - seems to stand > up to vibration, but it's HEAVY. Some cast iron, > like that previously used for engine blocks, can > be pretty good but will fracture on a sharp impact. > I've seen old cracked engine blocks too. > Cast iron is brittle.That's why they used to use wrought iron - but it was expensive. Then making steel got super cheap and that was that. Whole generation learned to treat and alloy steel to get almost whatever you want > Plastics - they start 'crystalizing'/decomposing > the instant they're made. Not all of them. Like steel, there is a huge range. There's many a radio case made of 'Bakelite' or stuff skinned with 'Formica' or floored with 'linoleum'....still functioning Epoxy and glass fibre PCBs dating from the 1970s are still OK, as are phenolic resin items PVC however is very short lived, In the sun Nylon is intermediate - UV ageing often gets it Jury is still out on polycarbonate, ABS and ASA. In fact one of the eco gripes about plastics is that they *don't* degrade. Nevertheless there are plastic gobbling bugs thriving at the bottom of the sea apparently, eating all those microplastics. Beware the SweepingStatement... -- WOKE is an acronym... Without Originality, Knowledge or Education.