Technical Rebuilding a 1930's tail light

Somehow I lost a thread I was reading on the HAMB about rebuilding a Model T Tail Light, so I'm asking this question. If a tail light has TWO sockets and you want to convert it to 12 volt and use the best sockets on the market, have running lights, stop lights and turn signals, what bulbs will you use, how many contacts, and TOTAL number of wires coming out of the back of the light housing? What is the perfect gauge of the wires?

REASON FOR ASKING? I want to run the wires in a tube down the forged light bracket, and need to know what size tube will allow all the wires to fit. I'll be 71 next month, too old to wire anything, just want to leave finished brackets for the next guy. Thank you!

Bob

 

There will be 4 wires, these wires will be two from each socket. They come with the sockets you purchase. The size of the wire is dictated by the manufacturer of the sockets you purchase.


Edit: Thinking about it, you may only have one wire from the socket, I was thinking the 1157 bulbs sockets.

 

Okay Bob- what day is your birthday in Dec? I'm the 12th, Mrs. Yankee is the 16th, and our infamous middle Yank, Daniel was born on the 7th !

 

so it's the 12 days of Bob at your house... pretty cool !

 

I guess if you will have two sockets in each light and want turn, stop and running lights I guess it will depend on what you are using for a turn signal switch.
If you use a turn signal switch that will turn off the brake light on the side that you are signaling, ( you know, that uses the same element for turn and brake light function) you can use both sockets/bulbs for all three functions and that will give you two wires from each socket, with the housing grounded. Use 1157 bulbs.
If your turn signal switch does not turn the brake light function off on the side you are signaling, you can use one socket for brake and running light and the other socket for turn and running light. This would also use two wires for each socket. Use 1157 bulbs.
If you want to use only one socket for running lights, turn signal and brake and the other socket for just running lights, you will need the brake light canceling turn signal switch and you will need only one wire from one socket and two from the other socket. Use 1157 for the three functions and 1156 for the running light only socket.
You don't say what light you are working on but if the sockets are mounted completely inside the housing, you may be able to connect the wires together from both sockets inside the housing and end up with only two wires exiting the light assy.

As we got off topic a little with birthdays, My Father was born Dec 2. I was born Dec 30, and my son was born Dec 16... all exactly two weeks apart.

 

Mine is the 23rd. Dad's was the 10th.

 

Not a bad idea to run a ground wire as well up the stalk too, as good paint will prevent the electrons from finding their way.

 

If this got bead blasted and new sockets pressed in the old sockets would be safe to use? No idea what the odd stuff is or how it worked, gut it and run whatever the total number of wires out the center and into a conduit of unknown diameter.

 

If one ground wire is added why not two so the other socket has one? Should they be a larger size?

 

https://www.amazon.com/uxcell-Socke...ocphy=9017876&hvtargid=pla-569308783907&psc=1

Some sockets like this would be easy to solder into your original bracket/bucket. You can get them at your local parts store. I'd grind the old bayonet parts out of the hole so one of the new sockets slide right in. Blast the old part to clean it all up. Then slide the new socket in to the right depth (check with a bulb in it to make sure it clears the housing and lense) and solder the outside of the new socket to the old bracket. Paint the old bracket stuff white, after taping off the inside of the new socket.

Since the same bracket/bucket holds both light sockets, a single ground is all that's required. Maybe you could weld a short stud inside the bucket to attach the ground wire.

I would remove the stubby pigtail wires and solder new full length wire into the new terminal ends. Less splices are better.

After all this fun you will probably start to enjoy wiring!

 

I had hoped to keep this a totally mechanical question, how many wires in a two socket tail lite will come out of the housing, and then into a conduit of undetermined diameter. With these sockets and the additional ground wire/wires we have totals of 3 to 8 total. The conduit may be a larger diameter than the forged bracket. The original socket part has to be as clean as the new sockets correct?

 

This is the plan, I'm NOT the guy running the wire, that shit scares me. IF the TWO new sockets have TWO wires each and a ground wire is added to each that is SIX wires. Taped together SIX wires will run through a 3/8 ID tube, if the tube has a 1/2 OD it will look good bent to mimic the forged early 1928 Forged bracket. WILL THIS WORK? If not why, and what would be needed to correct it? Thank you.

Bob

 

1 wire for tail light element,
1 wire for brake element,
ground each but do it inside,
buddy welds on a section of steel brake line bent to match the tail light stand and runs the wires through them to protect/secure the wires...

 

There is a large steel brake line that NAPA caries, that was my first thought until the wire total started climbing.

 

One ground wire can serve the whole light assembly.

I don't recommend using brake line for anything structural like the taillight stalk. Find some mild steel round tube with a bit more wall thickness. I remember way back when we used some brake line tubing for sculpting a rib on a body panel, and it became brittle when we welded it. Not really detrimental as a rib on sheetmetal, but not what you want when it's supposed to hold up a light.

 

Just me; but I would only run two 14 ga wires; one tail and one brake/signal. Get the old sockets out of the bracket, blast the bracket, solder the new sockets in place, and connect the appropriate wires from both sockets to the two feed wires.

If for some reason you don't think you can maintain a ground from the bracket to bucket to stand to chassis; then add a third wire for ground.

 

I want to use the tubing to house the wires, KEEP THEM DRY IF IT RAINS OR SNOWS. I NEVER AT ANY TIME SAID it would replace the FORGED STEEL ORIGINAL BRACKETS. The thread was started to find out the TOTAL NUMBER OF WIRES, once I know that I can find a tube that will fit on top of the FORGED BRACKET in the photo. People wonder why I'll die not understanding electricity.

 

Ah, now I understand. I thought you were replacing the forged bracket. I actually made a new tube/bracket to mount early A drum taillights about 30 years ago. I didn’t use any of the original forged as I wanted them pulled in tighter and lower. And all the wiring hidden. There’s no way I will remember the size though.

 

The Cadillac tail lights will be on eBay later today, I can't deal with the mental problems they cause.

Bob

 

So that's what's wrong with you guys!!?? This ain't gunna end well with Bob playing with lectrick. Be careful.

 

Don't sell them, Bob- someone will be able to set them up for you!

 

I don't like looking at things that bring up bad memories, they have some value I can turn into fuel oil.

 

I'm going to give this one last shot, it is a MECHANICAL FABRICATION question NOT a wiring question, nobody can explain that shit. The 1930 Cadillac tail light housing has TWO sockets, I want to replace the sockets with new metal ones. The goal is for someone someday to be able to provide running light, stop light and turn signal using the two new 12 volt sockets. Somehow power comes from somewhere to do this through wires, up the forged steel original Ford tail light bracket. I want the wires to be inside a steel tube to protect the wires from the weather. Here is the question, HOW MANY wires come back from where ever, then up the bracket and into the back of the tail light body? I don't need to know what they do inside the taillight, just need to know how many wires and the gauge of the wire so I can buy some tubing to bend up. Two wires, Three Wires, or more? I'll be dead before the wire gets run, just making brackets for the next guy, hope it is my grandson. Thank you.

 

Might be a good idea to understand what each component of a vehicle does if you're going to build one.
Two sockets with one filament each?
Ground through chassis?
12 volts with ten feet or less from source?

Two 14 gauge wires

 

I have several books on each part or system in a car, probably half dozen on electricity alone,
This is my main go to for traditional wiring

 

Look at the sockets and see what kind they are.
Also we need to know if both are the same diameter.

Important to know what kind of socket they are as well. The bulb has two tits on opposite sides of it, the tits slide through the slots in the socket and twist into place.
Now. If the socket is made for a single element bulb, the holes in the socket at the bottom of the slots will be the same depth. If made for a dual filament bulb, one will be higher/lower than the other.
Take a Google and look for an 1157 and 1156 bulb, you’ll see what I mean.
The single filament bulbs use one wire, dual filament bulbs use two wires.

Now here’s the deal, if you have an empty socket, you can clean up the inside with a battery terminal brush, use the part that cleans the cable end.

Now the good thing is if you can get it clean inside, you should have a good ground for the bulb and all you need is the “pigtail”. It comes pre-made and fits into place.

Only thing I can’t recall is if they come with a new spring or not? Or what ever is used to keep tension on the bulb.
I’ll let you know later if no one lets you know, have to make a trip to autozone. In fact I’ll take a pic of what they have hanging up.

 

Look at post #8. He doesn't have "sockets", he just has funky side slots and weird contacts built into the base of the light. That's why I was suggesting he modify it to use a modern style socket.

I guess he needs to decide if he wants the lights to include turn signals or not. Need to know what he wants to do before he can decide if he needs single filament bulbs or double.

 

Running lights, STOP lights, TURN SIGNALS 12 Volt system. How many wires come out of the car up the bracket and into the tail light housing? TWO TAIL LIGHTS one on the Left one on the Right. What is the total number and safe gauge wire to run through a protective conduit?

 

Use one new socket that takes a two filament bulb.
Ground through bucket/stand/chassis.
Run two 14 gauge wires through conduit

 

Thank you! I can fit four wires in the brake line, so I'm all set if the rules change and I need more. Bob