Flashbulbs

[mickeyobe]

I have been given a musty smelling old box containing 16 different kinds of flashbulbs. They range from tiny AG-1's to a bulb the size of a 100 watt incandescent bulb that is filled with crumpled foil.
They should make a nice display.
The left overs will be inserted in old cameras and flashguns.

I do not want these bulbs to fire from any cause including static electricity.

If I coat their bases with clear nail polish will that act as a sufficient insulation to prevent their self destruction?
Will it also prevent discolouration of the mostly brass bases?

Mickey

[Stephen]

Flash bulbs should not fire from static, they might fire with say a Van den graff HF machine connected! The voltage of static is high, but the power very, very, low. Varnish might stop low voltages getting to the pins, but not static. To fire one pin must be earthed anyway, if both are unconnected even a high voltage will not set them off as there is no real circuit.
I have never heard of any firing accidentally, in many years in the Photo trade.....I am also sure people have had them go off, but I have no real evidence.
Stephen.

[Stephen]

The mains sized bulbs are probably PF100 or PF60, I think the guide number for the PF100 was over 220, just a little more than the usual small electronic units!!! I used to use PF60 in multiple firings for large building interiors, twenty in all on bulb exposure!... they were not cheap, even in the late 60's.
Stephen

[mickeyobe]

Thank you Steven.

Years ago - about 1959 I think - I had a sleeve of 12 Philips No 5 bulbs go off in my hands. So I am living evidence. I don't know what set off the display but after the first one they went off one after the other - approximately. I think some may have fired two at a time.

Mickey

[Stephen]

You must have been the fabled exception to the rule! I know the shops worried about accidental firing, but it never happened to stock in the shop. For insurance, the surplus stock was kept away from film, and any heat sources, and there was a strict stock limit on the quantities for safety reasons.

The small bulbs could be set of by close proximity to another going off, so the packs wrapped the bulbs in silver paper, or plated plastic recessed packing to minimise the risk. Some earlier makers only packed them loose and that's where trouble occurred.

I do recall Flashcubes all firing at once!!! Kodak and Sylvania said it could not happen, but it did, and risked a burnt forehead with the standard 110 designs, made worse with make up on the forehead. Hair with lacquer on it was also in danger of being singed. Kodak moved the cube socket as far forward as possible or put it on the end on the camera for this reason.

I handled the PF 100/60 bulbs with great care to make sure they fired only as needed, as they blinded you if you were looking in the direction of the bulb.

Stephen.