which LED bulb for old-fashioned inspection lamp?

Since it will be inside a metal cage and with your stated requirements for plenty of uniform sideways light I would go for a cheap and nasty corn on the cob type at the highest wattage you can find. No diffuser. eg

You may need a diffuser or shield to make it bareable to be near. Mine has a metal plat to obscure the lamp on one side of the cage.

Big advantage is that after long periods of use it will barely have the chill off and will survive drops better than a fragile filament bulb (but if you drop it far enough or into water all bets are off).

I think what you want is a high powered 'corncob' bulb BUT these dont come easily in bayonet, so a complete new lamp assembly may in the end be cheaper

Also battery powerd lamps are possible thase days with decent battery life and are often handier than haing a lead trailing

ObDIY; In my case, made from a Coke can ...

Which is the single biggest advantage. The bulbs in inspection lamp generally only survive a few hours. I bought a rechargeable LED one.

Not thought of getting a re-chargeable LED one? Much safer than mains, and no trailing cable. Decent ones run a very long time on a charge.

BTW, even with a cabled inspection lamp, a low voltage one makes sense, as the bulbs are more robust. Even rough service mains ones didn't last that long here.

Overheating of LEDs in a fully enclosed lamp could be an issue, is strobing of moving parts being inspected likely to be an issue?

A "filament" style LED would give plenty of illumination to the side, but I'm not sure how well they'd stand up to the rough and tumble of an inspection lamp ... maybe the corn-cob type, or just stick with rough service GLS?

Even the 5W cheapo one from Aldi/Lidl with a magnet on the back can serve as a useful source of good light in a tight spot.

Especially not when dropped.

Thanks for all the points here. I had forgotten about the corn cob lamps, which would be good except that as said they seem to be difficult to get in BC.

I should say that I am not using this for actual 'inspection', but for general illumination of the loft whilst some plumbing work is going on. I have some small fluorescents already up there but thought of hanging this up high for general illumination.

I do have a cheap Aldi/Lidl rechargable LED inspection lamp from a few years ago, but I expect technology has come on a long way since that. This may be usable for the close part of the (plumbing) work however.

I may just put the biggest CFL stick light I can find in there (or stay with a service GLS) for this job, and see how well that provides general illumination

Thanks, Jon N

A 'filament' style bulb might not be ideal but it should be considerably more robust than the thin white hot filament of a tungsten bulb.

Search eBay for B22 15W (or other popular high value) avoid the ones coming from China unless you can afford to wait. I'd be prepared to use them in something with an earthed cage around it. I'm a bit wary of how well made some of the cheapo Chinese corn cob LEDs are.

jkn has brought this to us :

A 'corn cob' LED is what you need, but be wary of too high a wattage - LED's will not like heat build up in an unventilated lamp unit.

'Corn cob' LED's are rather like a corn on the cob which you would eat. LED's around 360 deg of the sides and more on the end face.

Mine is the old metal wire cage style. No build up of heat at all. It used to be insanely mad hot with a 100W bulb in it though.

I would have thought the filament style would be ideal in this case. LED hut do a frosted one as well if you want with the same radiation pattern as a normal GLS lamp.

Why not install a traditional fluro tube as a permanent addition the loft? It will come in useful year after year then. Also much easier to pop your head through the hatch and flip a switch, than tit about with portable lamps on wires etc.

Actually, as mentioned in my followup post I do have a couple of florrys in there ... however I mounted them a bit low down (ease of installation) and although useful they do not illuminate the whole area sufficiently. I would prefer to move/improve those in truth, it's a round tuit issue...

Cheers J^n