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Werner 10-20-2021 02:44 PM

Mounting headlight bulbs
 

2 Attachment(s)
Guten Abend A-Spezis.

I have a question about the correct installation of the headlight bulbs. There are two different bulbs. One with two straight, horizontal filaments. The other has a straight horizontal and a triangular tip.
Since the bulb can be mounted vice versa, the question arises as to which filament must be pointed upwards?

redmodelt 10-20-2021 05:58 PM

Re: Mounting headlight bulbs
 

If you look at the bulb with the filaments horizontal, one is on center the other is off set, the off set one goes on top. For best light, the filaments need to be horizontal. Use the bulb with the inverted V. The correct bulbs would have had both filaments V shaped, but we work with what we can get.

Bob C 10-20-2021 06:50 PM

Re: Mounting headlight bulbs
 

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Like redmodelt said both filaments should be V shaped.

Badpuppy 10-21-2021 09:45 AM

Re: Mounting headlight bulbs
 

1928 H-type used 21/3 CP bulbs. The brighter filament is centered on the bulb axis, the 3 CP filament is offset 1/8" above center. The socket is centered in the early reflector.

The later TwoLite reflector located the socket 1/16" above center. The bulbs used have filaments equally spaced 1/16" off center. This locates the lower filament at parabolic focus, with the upper (dim) filament 1/8" above.

Later bulbs may be used in the earlier reflectors, with minor aim readjustment.

Filament shape seems to be determined by manufacturer preference, but the V-shape would tend to produce more of a pin-point.

Badpuppy 10-21-2021 10:08 AM

Re: Mounting headlight bulbs
 

To answer your original question, the first bulb appears to be 21/21 CP, in which case orientation doesn't matter. The other I would guess is 50/32 CP. You should match your headlight bulbs.

Early manufacture bulbs were conveniently marked "Top" or "Down", but that nicety is not available on modern bulbs. You just have to try it one way and then reverse it because, of course, you guessed wrong.

Werner 10-21-2021 10:25 AM

Re: Mounting headlight bulbs
 

1 Attachment(s)
Many thanks for the hints!

Quote:

Originally Posted by redmodelt (Post 2068566)
... The correct bulbs would have had both filaments V shaped, but we work with what we can get.

Yes that's true, unfortunately. Often the quality is really bad. As an example, the light bulb shown at the end: It only had to light up for no more about 2 hours. But the glass of the pear has already turned a lot smoky black inside. https://www.fordbarn.com/forum/attac...1&d=1634831022


Quote:

Like redmodelt said both filaments should be V shaped.
Does everone know a seller or part-no.? Don Snyder don't offer this.

bavArian 10-21-2021 11:24 AM

Re: Mounting headlight bulbs
 

Werner,


Snyder's 'A-13007-12' should have both filaments in V-form. I can take a look tomorrow as I ordered 2 spare bulbs some time ago. (parts are inside the car and that's a couple blocks away in a garage)


Greetings from Bavaria,


Daniel

Werner 10-21-2021 01:34 PM

Re: Mounting headlight bulbs
 

Daniel,


nicht ganz. This Bulb that you mean is a 12 V type. Ich need 6 Volt.

Werner 10-21-2021 02:13 PM

Re: Mounting headlight bulbs
 

Männers,

it took me a long time to understand the slanted light on my white house wall, regardless of the switch position I or II. One of the many previous owners confused the cables of the two filaments of one lamp with one another! This is now noticed when I mounted the other lightbulb with "V" + "-" filament.

But I'm insecure: With "-" + "-" filament bulb I have a clean separation between city lights and high beams. But with the "V" + "-" filamens the horizontal light bar is very blurry. And the reaction to the adjustment of the focus changes only a little bit. The further I tighten the screw, the higher the cone of light rises.

Badpuppy,
yes, the "V" + "-" type is 50/32. The "-" + "-" light bulb shows "Vijaylux (?) 1000".

Bob C 10-21-2021 02:31 PM

Re: Mounting headlight bulbs
 

1000 = 32/32

Badpuppy 10-21-2021 03:00 PM

Re: Mounting headlight bulbs
 

I made a list a while back -

https://www.fordbarn.com/forum/showt...ight=headlight

The reason the beam rises with adjustment is due to the offset of the filament with the parabolic axis of your early reflectors. You must focus first, then re-aim the lamps. It would be best to match the bulbs to each other.

Werner 10-28-2021 02:02 PM

Re: Mounting headlight bulbs
 

Quote:

Originally Posted by redmodelt (Post 2068566)
... For best light, the filaments need to be horizontal. Use the bulb with the inverted V. The correct bulbs would have had both filaments V shaped ...

I would like to ask again, because my light settings gave an unsatisfactory result. I've tried with a) 1 + 1 straight filament and b) 1 straight + 1 triangular tip.



With a) I have a fairly recognizable light elypse for low and high beam.
With b) the high beam is very unfocused.

There is also only a little difference when I try to adjust the focus. I have the best core when the light bulb is as close as possible to the front of the glass. But then the horizontal guidance of the frame is no longer effective.


Any ideas? (Perhaps I'm too exacting/fastidious between the ears?)

Badpuppy 10-29-2021 08:28 AM

Re: Mounting headlight bulbs
 

"Focus" is achieved when all light rays are reflected forward in parallel. This means the pattern on the wall will be 8 inches (20 cm) in diameter, same as the reflector rim, at any distance. Remove the lens to get a circular pattern, the fluted lens simply spreads the beam horizontally. There will also be ambient light from the rays that do not strike the reflector.

The reflectors may need polishing. Service bulletin recommends wiping the silver plate with carbon black (powdered carbon) if tarnished. Silver polish may also be used.

Kurt in NJ 10-29-2021 09:22 AM

Re: Mounting headlight bulbs
 

2 Attachment(s)
These are halogen bulbs, the filaments are curves, not the V shaped, the focus is pretty good, when I put the old original "Mazda" bulbs in the edges were sharper.
Original bulbs of the era were filled with halogen gases to reduce blacking of the glass
The modern production bulbs I have seen look like no effort was taken to align filaments properly

Werner 10-29-2021 03:42 PM

Re: Mounting headlight bulbs
 

Badpuppy,
thanks for the tip about the focus. I will now try this without scatter glass look.


Kurt,
thanks for your advice too!
Please tell me, what halogen bulbs are you using please? The reflective image from your house wall is impressive, my bulbs are scattered miles away from that.

Werner 11-10-2021 08:02 AM

Re: Mounting headlight bulbs
 

Hi,

I want to ask again about the halogen bulbs. Snyder offers it as a two-filament bulb for 6 volts. Is it correct that I can keep the previous reflector for this?
The filament position looks shorter in the halogen bulbs and is therefore positioned closer to the inside?

Badpuppy 11-11-2021 09:12 AM

Re: Mounting headlight bulbs
 

Snyder recommends alternator for halogen bulbs. I don't know why; 25 watts is about the same as 32 CP. You are probably correct that the geometry is wrong. But your concentric reflectors make it more difficult to focus any of the later bulbs as well.


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