Trade Rated?

But (when I bought some) they had a clear envelope through which you could see the halogen capsule.

The LED itself - yup. The problem in mains rated applications can be the support electronics when exposed to vibration.

(I expect you could do a vibration resistant one using the long sting filament style LED strips since you can get away with a very simple "driver")

Is this one of the original Hoover senior style machines with the illuminated headlamp/log on the front?

Actually a Panasonic. But same idea. The original bulb lasted weeks. A 'normal' type that fitted, days. So gave up on it, nice though it was.

The vacuum must be 30 years old. Still as noisy as ever, but does its job very well. Next door must have had half a dozen Dysons in that time. ;-)

no, they have extra filament supports

Lots of people did, from moron to genius. Better to use the halogen type if you're not prepared to replace the luminaire for some reason.

NT

And just how does that reduce the light output compared to a same wattage GLS?

Every filament support conducts heat away from the filament. That's heat lost plus it reduces the temp & thus light output of nearby filament.

NT

I bought some rough service bulbs years ago for a student lab experiment because

The trouble with those is that they seem to fail very quickly. I have a box full of dead ones (mostly Osram). They all seem to have the same failure mechanism - they flicker for a bit with some of the strings getting extra-bright as the others go out and then they die completely.

John

So far I have had reasonably good performance from the LED hut ones I got. Most are still running after lots of years. I have a few 40W on dimmable that lost brightness with age, but most were ok.

In one.