Which filament is low beam?

burner31

Well-known member
Which filament is which on a 6V bulb?
 

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I've never seen filaments like that before. I'd guess the straight one is parking, as it looks thinner.


Actually that looks like an early parking/driving bulb. Since both filaments are in the center it won't have high/low beam aim.
 
I think that bulb is the new replacement 50/32 cp bulb with the wrong
shape filament. The picture shows what they should look like.


Bob
 

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I would turn on the lights and see what filament light up then push on the high beam switch and see if the other filament light up. Wiring diagrams are great but many times observation is more accurate.
 
From what I gather, the shorter stems hold the brighter filament, which should be placed lower than the other. Frankly, I can't tell any difference in brightness.

Your #1188 is a 50/32 bulb, I dunno what Bob C has.

A problem I found in my car was one of the bulbs' filaments weren't aligned with the contacts and had a 'dip to the left' when dimmed. The other bulb was an original Gross branded 21/21 cp, with ridged edge around the front of the glass. Still works.
 
It was an optical illusion, and now I see one filament is below the other. The filament on center should be HI beam and the filament placed above center should be LOW beam.
 
It was an optical illusion, and now I see one filament is below the other. The filament on center should be HI beam and the filament placed above center should be LOW beam.


As Tom said, "The filament on center should be HI beam and the filament placed above center should be LOW beam."

It is not how bright the lights are but how the beam is aimed, the shape of the reflectors and lens.


redmodelt has an often overlooked and before now new impossible to get right comment.


Ever have one of those focusable flashlights? The bulb output is the same but the light is more useful when focused even seems brighter. The correctly shaped reflectors are available that are also aluminum coated so as to be as close to polished silver without worry about tarnish.
 
I was thinking of going to Australia once...until I seen what panda's REALLY look like
 

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Yes, the small filament is low beam

Well, Bratton's instructions are wrong. Here's how filaments work:

Longer filament = higher resistance = lower current = less light (dim)
Shorter filament = lower resistance = higher current = more light (bright)

The filaments are equidistant (1/16") from the center plane that intersects the base contacts, so the original headlight reflector opening is elevated to compensate for this, causing the brighter filament to be adjusted along the parabolic axis.

http://www.fordgarage.com/pages/Aheadlampreflectors.htm

So install the bulbs with the longer filament on top and make sure it's the one that illuminates with the light switch in dim position. If not, either spin your (repro) reflector 180 degrees or swap wires at the conduit socket.

Back to bulb spinning.:mad:
 
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