7" Headlamp comparison +

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Since V8 #322 was a tad late hitting the front doorstep, Bruce Blair and
I have had a few emails pass back and forth prior to his printed concern
in #322: "If those Cibies are the old concave type lens (makes me think
they are, since you mention P45 base bulbs), they were designed before
the advent of halogen bulbs. The concave face was supposed to be more
self-cleaning than the typical convex lamp.

"The P45-based halogen bulb was not an approved E-Code bulb in the days
that
I marketed Cibies. They were produced as a way to get more light out of
old
lens assemblies. The Cibie factory vigorously opposed their use in the
concave lens lamps, since the placement of the filament in the focal
point
of the parabolic reflector put it too close to the lens glass, and would

cause heat stress and cracking. This was the standard 60/55w variety. If

there is a lower wattage P45 base bulb available, it should lessen the
risk of cracking those expensive lenses."

**********

My reply was: "Bruce, much appreciate your input and will readily admit
I learn more about headlamps and their various bulbs, if not daily,
certainly frequently.

"I'm a bit confused on the 'self-cleaning' aspect, but since these lamps
are
quite bulbous (I assume to accommodate the city lamp) the bulb
will be more than somewhat distant from the inside face of the lamp.

"The sole importer (and a friend of mine) where I source the lamps did
not
caution against higher wattage, but implied anyone currently using
tungsten
bulbs in their lamps would be 'astounded' by the brightness of the
45/40W halogen
bulbs with the P45 base.

"From your comments, I might well cease offering the 60/55W halogen
bulbs with the vintage lamps (just in case)."

***********

To which Bruce replied: "The old lamps I was talking about have a
recessed (concave ) face.  If these are bulbous (convex), then they
should be fine.

"The ones I remember had a Cibie part # of 66-70-022 - not sure if they
are still using the old numbering system."

**********

And to which I replied: "Bruce, thanks once again for your input. The
outer point of these lamps must be at least 1/4" farther away from the
bulb than a 'normal' lamp, let alone a concave one.

"I checked to see if I could find the part number you included, but came
up blank.

"I do appreciate your concern and input,..."

*********

Final notes: There are four (??) embossed E2 'stamps' on these
headlamps. However, as Bruce pointed out, that does not mean they were
approved with the P45 based halogen bulbs. My supplier / main
distributor was unconcerned with the use of the 45/40 W halogens in
these lamps. I have seen E3 on some lights, and assume it is something
like the Snell (?) dating on crash / safety helmets. Comments?

"If there is a lower wattage P45 base bulb available, it should lessen
the
risk of cracking those expensive lenses."  At $88 per lamp (not
including bulbs) they are not inexpensive, but are $52 less expensive
than Carellos and $62 less expensive than Lucas PL reproduction lamps.

Thank you all for your patience and should anyone return a #7" - CRA
lamp purchased from me, had been using a 45/40W halogen bulb, and which
was broken from the inside out, I'll return your money in full.

Biba
Irwindale, CA USA

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