The Lamp Room

Not sure the poll says that the humble 70's pop-pack wasn't good, just reflects the fact the Europa was slightly better. If Thorn had a quick-release coverplate on their older pop-packs, it'd be an even match! That for me is the only reason the Europa JUST won out over the pop pack. I personally thing the Thorn offerings from back then are extremely high quality.

I don’t think the 70s thorn lamp holders were as good as Europa some i come across now are really suffering

On the flip-side tho, I've seen Europas with burnt out lampholders too. Maybe it's more a case of people installing tubes with bashed in pins, than a case of either having shit lampholders. One snag I've noticed with the Europa lampholder, is the little bit that always snaps off on on, other or both side. It's not important in terms of functionality or safety, just looks a bit shit!

Do they differ in how they provide the contact to the lamp pins ? - Maybe in the ones that burn the contact is deeper inside so have problem with lamp pins with tapered ends, or is not as springy ?

Fitzgerald's pull-to-release lamp holders are definately less springy than the competition, I've been using one just today and after the lamp is inserted, you really have to give both lamp holders a tap to fully insert the pins. Thorns aren't bad, but slightly less springy than the Europa, especially if the springs have gone a bit rusty (as they do). By far the best IMO is the Crompack 3, the lamp holders are mounted on a hefty piece of spring steel and hold the tube very securely with little chance of the pins being left not fully inserted.

I think part of the problem (with burnt lamp holders) is people who don't know what they're doing. I've seen the situation several times now at work when apprentices have been relamping, the lamp pins are just sat on their tips on the contacts of the lamp holders, barely making a connection. Usually all the tubes requires is a small 'wiggle' to allow the lamp holder to seat properly, which is something I always do when relamping any fitting with pull-to-release lamp holders.

The actual copper contacts inside the holder probably make a big difference, if they are tight and the end cap spring is weak then it might not get proper electrical contact, hence the high resistance, heat and burning up.
That’s one thing that twist lock has going for them, a positive engagement.

The biggest difference with twist holders is that the lamp pin scratches against the contact when lamp is inserted. So it provides for a fresh contact point even with aging socket (that have corrosion set in on the contact surface)

Some T8 tubes nowadays are 1mm or more shorter than spec, maybe that was a contributing factor