my LED light from a vintage automotive lamp

[cledry]

I bought this small light from tin machine a few weeks ago. It turns out to be a reverse light used on General Motors products from the 1930s to the 1950s. The lens dates this one to about 1939.

It uses a common automotive bulb that is still used and which fits a bayonet mount.

I researched different LED bulbs that used this base and decided to use this one for several reasons. It has a built in soft start circuit, a built in lens, a built in heat sink and a fairly wide voltage range.

I had to cut a bit with a Dremel tool on the carriage bolt that holds it all together which was swaged in place. After that it came apart easily. Initially I soldered the negative lead to the spring and the positive to the old centre terminal, but didn't like the result. So I now have a piece of an old gold speaker bi-wire jumper soldered to negative and attached where the carriage bolt comes through the housing. Everything is heat shrinked.

I had to soak the lens and housing in acetone to remove a black tarry substance that apparently was a seal of some sort. I shall replace it with a rubber or cork gasket.

All rewired using a long cable that was formerly a 12 foot RCA to RCA connector. New LED in place.

All buttoned up. Cleaner but still with some age to it.

I hooked it up to a 12 volt power supply and it works really well. The old glass lens disperses the light but enough projects forward. On 12 volts it will light up one traffic lane clearly for 40 feet but is visible much further. I plan to run it on a higher voltage, not sure if that will increase the output. The LED is listed at 200 Lumens but it doesn't say at which voltage.

I'll be deciding on where and how to mount it next, followed by wiring and battery construction. I will also be working on a suitable tail light.

 

[deven_science]

Well done.

 

[Harold_B]

Nice! Likely since there's a soft start circuit there's a regulator too (most likely current). The input voltage range on the box shown as 12-24VDC so unless the light turns on dim at a lower voltage then the 200lm rating is for the full range. The only suggestions I can make if you want to keep the current bulb socket is to use an 1157 replacement. Those typically are omnidirectional so you would need to make the inside of the light housing reflective at the minimum, preferably an actual parabolic reflector. On the other hand, if you don't mind gutting the housing you could retrofit a copper slug or some other heatsink and mount a Luxeon M LED. They are 12 VDC so you would need a voltage regulator also. Probably more input than you really asked for so sorry if I seem pushy but if you want brighter I think you'll need to ditch that LED bulb.

 

[cledry]

Not too much input, too much output.

200 lumens is fine for riding on the roads. The Luxeon M uses too much power, almost an amp is too much for me and 900 lumens is overkill. I had a light on my Mtb and at 400 lumens it was blindingly bright. This bulb actually did light on a single 9 volt battery but was very dim.

Nice! Likely since there's a soft start circuit there's a regulator too (most likely current). The input voltage range on the box shown as 12-24VDC so unless the light turns on dim at a lower voltage then the 200lm rating is for the full range. The only suggestions I can make if you want to keep the current bulb socket is to use an 1157 replacement. Those typically are omnidirectional so you would need to make the inside of the light housing reflective at the minimum, preferably an actual parabolic reflector. On the other hand, if you don't mind gutting the housing you could retrofit a copper slug or some other heatsink and mount a Luxeon M LED. They are 12 VDC so you would need a voltage regulator also. Probably more input than you really asked for so sorry if I seem pushy but if you want brighter I think you'll need to ditch that LED bulb.

 

[Harold_B]

I see. I had the impression from your post you wanted more light. I understand that about 100lm is plenty to be visible. Another option would be a Bridgelux SM4 at about 450lm, 350mA. I am never happy with enough light. As long as I can switch to a dim mode for oncoming traffic I want it as bright as possible! Currently my headlight is 1400lm when in the bright mode....

 

[redrkt]

could you post up a couple more pictures of how you did the wiring on this?

 

[kingfish254]

Never seen one of those LEDs. Nice work!

 

[expjawa]

Maybe I missed it, but how are you planning on powering it on the bike?

 

[Porsche930dude]

nice. the early jeep cj-2a uses that style bullet lights in the grille they look very similar to that. but theyre not chrome and getting expensive.

 

[cledry]

Maybe I missed it, but how are you planning on powering it on the bike?

I'll post photos of that soon. Basically it will be rechargeable Lithium Ion batteries putting out 14.8 volts, will give 9 hours of run time for headlight and tail light.

 

[cledry]

could you post up a couple more pictures of how you did the wiring on this?

I'll see what I can do but basically there isn't much to show. I had an old shielded cable that was a RCA to RCA cable, I used the shield as negative and attached it to the chassis of the housing. The centre is positive and is soldered to the centre pin of the lamp holder. All the switching will be on the case that will hold the battery.

 

[XC204]

Nice I'v used SuperBrightLeds stuff before never noticed that bulb thanks.

 

[LukeTheJoker]

Nice job! That light looks spot on for a Rat Rod Bike!

Luke.

 

[cledry]

I've ordered the Lithium Ion cells the common 18650 3.7 volt jobs. Going to start with 4 for 14.8 volts and see how that does. Plan to mount battery box above the kickstand between down tube and rear wheel.

 

[expjawa]

I've ordered the Lithium Ion cells the common 18650 3.7 volt jobs. Going to start with 4 for 14.8 volts and see how that does. Plan to mount battery box above the kickstand between down tube and rear wheel.

OK, makes sense. That's where I mounted the battery for my lamp on my last build off bike. But since I was using a disembodied 6V Big Beam flashlight, I was squeezing the battery case portion of it into that space. Wasn't easy. I expect that building your own pack will give you a bit more freedom, not to mention will be more compact.

 

[cledry]

I've ordered the Lithium Ion cells the common 18650 3.7 volt jobs. Going to start with 4 for 14.8 volts and see how that does. Plan to mount battery box above the kickstand between down tube and rear wheel.

OK, makes sense. That's where I mounted the battery for my lamp on my last build off bike. But since I was using a disembodied 6V Big Beam flashlight, I was squeezing the battery case portion of it into that space. Wasn't easy. I expect that building your own pack will give you a bit more freedom, not to mention will be more compact.

I want it to blend into the bike and be secure from picky fingers. Probably bend up a metal box on my brake.

 

[Sayisse]

I bought this small light from tin machine a few weeks ago. It turns out to be a reverse light used on General Motors products from the 1930s to the 1950s. The lens dates this one car navigation system to about 1939.

It uses a common automotive bulb that is still used and which fits a bayonet mount.

I researched different LED bulbs that used this base and decided to use this one for several reasons. It has a built in soft start circuit, a built in lens, a built in heat sink and a fairly wide voltage range.

I had to cut a bit with a Dremel tool on the carriage bolt that holds it all together which was swaged in place. After that it came apart easily. Initially I soldered the negative lead to the spring and the positive to the old centre terminal, but didn't like the result. So I now have a piece of an old gold speaker bi-wire jumper soldered to negative and attached where the carriage bolt comes through the housing. Everything is heat shrinked.

I had to soak the lens and housing in acetone to remove a black tarry substance that apparently was a seal of some sort. I shall replace it with a rubber or cork gasket.

All rewired using a long cable that was formerly a 12 foot RCA to RCA connector. New LED in place.

All buttoned up. Cleaner but still with some age to it.

I hooked it up to a 12 volt power supply and it works really well. The old glass lens disperses the light but enough projects forward. On 12 volts it will light up one traffic lane clearly for 40 feet but is visible much further. I plan to run it on a higher voltage, not sure if that will increase the output. The LED is listed at 200 Lumens but it doesn't say at which voltage.

I'll be deciding on where and how to mount it next, followed by wiring and battery construction. I will also be working on a suitable tail light.

These led lights looks awesome. Just one question from where could I buy them?

 

[cledry]

I bought mine from these people. http://www.superbrightleds.com/

 

[expjawa]

Digging up an old post. Any update with how the battery pack came together?

 

[LowpowerD]

I'd like a progress report too.
Very good work, sir. Could you run two 9v batteries in series for 18v?