Filament distortion from horizontal storage?

[Chris Kocsis]

Is there any danger of filaments bending or sagging permanently because the bulbs are stored horizontally?  This is obviously of concern only for significant lamps, particularly early carbon with horsehoe or other long filaments (e.g. Weston) that are supported only at the lead-in wires.  My guess is that permanent distortion is negligible or nonexistent.  Can anyone confirm?

Thanks!

[PCris]

This is a good and interesting question, and while I do not have a definative answer, I would tend to agree with your guess that distortion would be negligable or nonexistent. I have a few bulbs laying horizontally in my bulb cabinet so that the early bases can be viewed, and I have never had a problem with distortion, including one lamp that has a break in the filament at one of the leads, and even this filament looks perfectly normal. It seems very resilient.

What I have noticed on a few lamps with long hairpin filaments that had obviously been in service at one time (as evidenced by carbon "patina" on the envelope) is that the filaments seemed slightly distorted, possibly from the intense heat during service? Or was that a manufacturing fluke when the filaments were carbonized?

I hope other collectors will weigh in on this thread.

Regards,
PCris