Blackout Light Conversion to 12V

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Buster1
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Blackout Light Conversion to 12V

Post by Buster1 » Sun Sep 12, 2021 12:55 pm

I just acquired this really great blackout light! It’s got the protection guard and everything. Check out the date too! 1952! The wiring is shot, frayed, and cut in many places. I want to convert it to 12V by removing the original bulb and wiring up a modern bulb or LED of some sort.

I’ve searched the forum here, but can’t see how I can free the glass bulb from the housing. Is it even possible?

I’m thinking maybe of gently cutting the back open to extract the old bulb (green line in photo).

What am I missing? How can I replace the old bulb with something modern and not ruin this cool piece?
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Re: Blackout Light Conversion to 12V

Post by jnissen » Sun Sep 12, 2021 1:12 pm

It’s a sealed beam so there is no way to remove the bulb. It’s one piece. I looked into modifying mine for 12V but went with a newer design that did allow for a bulb replacement.

I’ve used it only on occasion so other than looks you could just leave it and clean it up.


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Re: Blackout Light Conversion to 12V

Post by Buster1 » Sun Sep 12, 2021 4:51 pm

So as a sealed beam unit, how did they replace bulbs when they burnt out? Was this whole piece discarded for a new sealed unit? Just curious.

I can’t find a way to open this piece up.
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Re: Blackout Light Conversion to 12V

Post by jnissen » Mon Sep 13, 2021 5:21 am

Yes the whole bulb assembly was replaced.


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Re: Blackout Light Conversion to 12V

Post by mdainsd » Mon Sep 13, 2021 6:03 am

The one you have has also been altered from the looks of it. Someone has opened the top of the slot across the front of it.

In WW2, the vehicles that were 12V used a 6V blackout driving light. There was a dropping resistor in series with it. Those resistors are still available today.
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Re: Blackout Light Conversion to 12V

Post by W. Winget » Mon Sep 13, 2021 6:19 am

Since it's dead, why not take a dremel, slice open the back portion like you have indicated, insert a 12V LED, JB weld it in place and then install it in the housing.
It's not very useful, especially at shows during the daytime... :D
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Re: Blackout Light Conversion to 12V

Post by YLG80 » Mon Sep 13, 2021 7:44 am

I would not hesitate to “Dremel” the creamy sealing compound around the back of the bulb where the wires are fried.
And I would post photos so that everyone could see how it was assembled :wink:
Cannot wait :lol:
And afterwards you can seal a new lamp socket or LED with epoxy. Take care of à correct grounding.
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Re: Blackout Light Conversion to 12V

Post by GPW1263 » Mon Sep 13, 2021 9:38 am

As they have already said, it's entirely do-able if you want to play with it and invest a little time. JB weld or other epoxy works wonders and as mentioned, use an LED bulb. I just recovered a blackout lamp that's completely rusted out on the back of the bulb. It went in the tub with the rest of the recoverable stuff, to be dealt with later.

An additional word of advice. If you remove the bulb from the front ring, take care not to damage (or lose) the retaining clips. Put 'em in a zip-loc bag and mark the bag with a sharpie.

But in the final analysis, if you have a nice vehicle and you feel you must have a working blackout light (even if only for braggin' rights) treat it to a new 12v bulb.

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Re: Blackout Light Conversion to 12V

Post by Buster1 » Tue Sep 14, 2021 5:07 pm

Cutting commenced! The outer layer is just rubber, and the bulb housing is pretty thin metal.

In the last pic, you can see some kind of flux or solder around the bulb housing for securing it to the main metal housing/opening. My soldering iron won’t melt it though.
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Re: Blackout Light Conversion to 12V

Post by Buster1 » Wed Sep 15, 2021 2:13 pm

Got it! Old bulb is out and glass intact. The Dremel bullet-shaped sander worked great to carefully open up an smooth out the glass hole.

Now I just need a LED!
1FA20CCD-A482-4E18-8250-6555DC15B752.jpeg
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Re: Blackout Light Conversion to 12V

Post by jnissen » Wed Sep 15, 2021 8:00 pm

Way to go. Surprised it cleaned up that easily. May need to try a similar mod on one I have here.


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Re: Blackout Light Conversion to 12V

Post by YLG80 » Thu Sep 16, 2021 2:55 am

Buster1 wrote:
Wed Sep 15, 2021 2:13 pm
Got it! Old bulb is out and glass intact. The Dremel bullet-shaped sander worked great to carefully open up an smooth out the glass hole.

Now I just need a LED!

1FA20CCD-A482-4E18-8250-6555DC15B752.jpeg
Waah, thanks a lot for the detailed pictures.
Was the old bulb simply tin soldered?

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Re: Blackout Light Conversion to 12V

Post by Buster1 » Thu Sep 16, 2021 9:39 am

YLG80 wrote:
Thu Sep 16, 2021 2:55 am

Waah, thanks a lot for the detailed pictures.
Was the old bulb simply tin soldered?

Yves
Hard to say. There were copper wires that entered into the metal housing, plus a lot of other hard plastic-like gook and stuff. It all cleaned and scraped away pretty easily. The actual bulb didn’t seem to be attached to well to the glass there, which was fortunate I guess. The bulb separated from the main glass wall very easily leaving a 1/4” hole. The dremel helped open it to 5/16 but it’s still a fairly small opening. I’ve been researching LEDS and anything that small seems to be fairly dim. Going to keep searching small halogens, or maybe motorcycle lights, etc.
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Re: Blackout Light Conversion to 12V

Post by jnissen » Thu Sep 16, 2021 4:41 pm

Believe me a high brightness LED can easily fit that area. It is a blackout light after all so it doesn’t need to be a 100W pencil beam!


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