I brought this up last year but did not get a satisfactory answer. Hopefully, the market has changed and someone has found a source for what we all could use and can pass it along.
The 6 volt, 32/50 headlamp bulbs I currently on my 1926 Model T have the two filaments side by side so that when the beam is changed from dim to bright, instead of the beam raising to light further down the road, the beam simply goes from one side to another. I have been searching for a source for a 6 volt 32/50 bulb with one filament on the top and one beneath it so that the bright beam shines further down the road instead of one side of the road or the other. Thank you. Jim Patrick
I think I posted to find a set of 15-17 head light sockets. They will turn the bulb to the correct orientation when installed in 18 up head lights.
Mark, did you say these were available in '18 and up headlamps, or that you were looking for them? If available, are they 6 volt 32/50 and where can they be obtained?
You are looking for bulbs with the correct orientation of the filaments, I am giving you an idea how you can get around the problems when using most of the bulbs supplied today.
The sleeve in the bucket can be fairly easy to press out and rotate so that the correct orientation may be obtained, of course you will have to re drill the focus screw hole. As far as I know the re pop head light bulbs have not been corrected. KGB
I need to add another bulb to that chart...there a 50/50 6 volt bulb available now.
After a drive in the dark and the rain on New Year's day, I decided to follow a friend's advice and fit LED bulbs, even though they are £52 (about $75) per pair.
I already had a DIY LED conversion in my stop-lamp with 36 red LEDs soldered together in pairs with resistors.
I encountered the same problem as Jim. The LED bulbs have just 2 'filaments'. One is supposed to shine upwards and reflect off the upper half of the reflector. As this LED is slightly further from the base of the bulb than the other, it gives the dip beam. The other is supposed to shine downwards and, when used with the dip filament, gives you full beam. But in the T headlamp they point sideways! I fitted them so the dip shines to the offside, so the beam ought to have been bent to the nearside. But when I fitted the fluted glasses, I got an oval beam from both - the beam is spread sideways.
On the road the improvement over tungsten bulbs (or halogen, which I have tried in the past) is ENORMOUS. Subjectively, they are about 5 times as bright as the old bulbs. And on main beam, the four filaments take just 2.1A total on 6v. On dip, they take 1.05A.
If I wanted to rotate the bulbs, I would not touch the housings, I would cut off the brass arm from the bulb holder, and solder on another (or the old arm with a small angle reinforcement) at right angles.
The bulbs I bought work on anything from 6v to 24v, but you have to specify either +ve or -ve earth.
The drawing is correct for the early or most of 1926 head lights that did not sit on the bar.
The filaments in the bulbs I have appear to align correctly with the adjustment screw horizontal to the socket.
The filaments do not align correctly with either of the head lights show above, as both are about a 45 degree angle away from correct.
They are correct for a truck if those head lights were mounted with the mounting flange horizontal.
Those lights were evidently left over from trucks that never were manufactured or sold.
Chris : Where did you get the LED headlight bulbs, and do you have a part number?? Thanks : Bruce
I have 2 comments and I am not trying to rain on anybody's parade but just want to make sure you guys don't spend a lot of money going somewhere only to discover that the city you were heading for is not located in the state that you drove to. The headlights and reflectors only will focus on bulbs that have the proper filament shape and I don't see any mention of that. Start with correct low candle power bulbs if you have some with the correct shape filament that is shaped like a teepee and not at all the shape of a horizontal straight filament stretched between two wide apart tie points. Check how the bulbs focus by following the procedure outlined in the service manual or service bulletin. Now check any bulbs you want to use to see if they focus at all since moving the sleeve and modifying the headlight bucket will have zero results if the filament shape is not a bulb designed for the headlight focusing system you have. Tail light filaments have the tie bar style filament to provide a broad wide light for viewing by the guy behind you while headlight bulbs are designed to put the light far out in front in a narrower beam that you can aim after you get it focused. Finally check the headlight amp drain since your electrical system will not be able to keep up with bulbs that draw more than 10-12 amps total and this constant quest for higher and higher power bulbs has no pearl of success waiting for it at the end if you end up with no way to power them. Now if you are doing this for a speedster and have an alternator already on the car then you only have the focus issue to solve. If you simply want brighter lights with the stock system I wonder why nobody is willing to re-silver the reflectors - it really helps a bunch when you have the right bulbs to go with it. Just massive amounts of light in front via LED is nice for YOU the driver but may be illegal if the guy coming toward you is blinded by your headlights. LED's clearly offer a brighter future but LED headlights is a much harder nut to crack due to briteness, focus, and aiming than tail light issue which is simply about briteness. LED's are on the way for headlights so if you convert your car to alternator thinking you need all that power, remember NOT to toss away your generator since in the not too distant future LED headlights will in fact arrive that are workable and then your generator will have tons of power without having too much power and you may wish you had not converted to the alternator.
Hope this helps and your mileage may vary.
I have seen some head light bulbs made in the last few years that have both a tepee and horizontal filament.
Thanks everyone. I have gone the route of trying to figure out how to modify my buckets to correctly orient the available bulbs, but I don't want to take the chance of messing up and ruining my buckets. I don't drive all that much at night if I can help it and I almost always can (help it). Hopefully, someone will come up with a headlamp bulb with filaments of the correct top to bottom orientation to allow proper focus of dim and high beams on our Model T's, like was available in the day. Until then, I will continue my search.
Note. The drawing above shows no gap in the rope gasket, but there is a gap of about 1" once it has been properly placed into the reflector rim groove. I knew an old timer back in the 70's, who drove Model T's in the day and told me that the rope gasket gap should be positioned at the bottom of the reflector, so that no water can flow into the light through the gap and, if any water does, somehow, get in, it has a way to flow out.
I'm in the UK and I bought them here:
good point about dazzle, but -
a) I checked the focus - the normal T adjuster does work - and as I said, the beam is a wide oval. I also made sure that the lamps were pointing in the right direction.
b) No-one has flashed me or otherwise indicated that the lights are disturbing to other drivers. And my 'ENORMOUS' improvement still means that they are not quite as bright as the common 7 inch Lucas lights used on 1960s MGs, Sunbeams etc!
I would think that any LED bulbs designed specifically for head lights should emulate the typical teepee shape so that is no surprise but there are many LED type concoctions on the market in the USA that pretend to be exact replacements for various bulb numbers and there are no two of them the same for any bulb number you might look up. Headlights are just way more demanding than other bulbs. LED's will soon be here for headlights no doubt about it since I had heard they were available in UK but had not seen any personally. Unfortunately they probably will not be available for 6V at least not right away.
John is right, you must use the correct bulb. I seem to recall that last year or maybe the year before this was discussed at length. The original poster intended to use regular stop/tail round bulbs with two straight filaments, one bright and one dim. Maybe a catalog even listed them as headlight bulbs, I'm not sure. It was pointed out that those bulbs were incorrect, and that the correct bulbs were the flat front bulbs with two teepee filaments. Charts and drawings showing how the light is reflected and focused on the reflector and pictures of the correct bulbs were posted along with explanations of why the stoplight bulbs wouldn't work. It was pointed out that the with the proper position of the filaments, even when they are both the same candlepower, you get high and low beam, (not bright and dim) although high beam appears brighter to oncoming traffic due to it's higher projection. As I recall, the OP and others basically called BS and decided that they were going to use the wrong bulbs since they offered bright and dim. Sometimes you just can't help someone.
I concur with John on the subject of re-silvering the reflectors. I had that done to two pair of reflectors and the increase in light output was quite noticeable.
Also, good ground path is essential; from the socket, through the lamp, to the fender iron and to the frame. A little rust here, too much paint there and the resulting lower voltage will decrease the bulb output.
The original bulb was a 21-2 or 3 combination. I can see no reason for going above 32 on the bright. What good would a 50-50 do you anyway? A stock 6 volt generator can't keep up with that kind of a draw.
Thanks Chris : Exactly which ones did you select? Bruce
Another thing to add, even back in the day there was more then one combination of filament, contacts and sockets. So even finding an era bulb does not mean the bulb will be correct.
I have the BA15d bulbs, negative earth.
They work on anything from 6v to 24v.
I have the stock Model T 6v system (with John Regan's regulator).
The circuitry inside each bulb manages the voltage, and it also arranges for dip to be one LED and Main to be both LEDs, without any modification to the car's systems or wiring.
As I said, the normal focus adjustment works. The only odd thing is that on dip, you see just the off-side half of the lamp lit.
I have read with some interest your happy experience with your LED bulbs. In your last post (at 4:49 pm) you mention that on dip, the off side of the lamp is lit. When you speak of "off side" I have to ask if you are referring to the center of the road and, if these LED bulbs, being European sourced, do have a bias for driving on the left hand side of the road and there by not suitable for here in America where, of course, we drive on the right hand side of the road? Cheers, Bill
That was a very interesting UK supplier - I tend to say a "UK Fun Projects" or "UK John Regan" as he apparently does similar voltage regulators for 6 and 12 volts as well as all sorts of very interesting LED bulbs including the headlights Chris are using. He actually makes a "bulb" that will fit in the model T rearlamp! I have been speculating in eventually designing and making one myself, but now this chap have done it, I won't even bother.
I'm in for making both my model T's LED equipped all-around and turn the max ampage on the generator down to 4-5 A.
John - take a 5 minutes ride down that chaps website and see that all his bulbs is found in 6V versions.
And remember: support our vendors also goes for a vendor from the UK.
I used the term 'off-side' to try to avoid confusion! I am in the UK, where we drive on the left, and the offside is the right. The ba15d bulbs have 2 connectors on the base and two symmetrical pins, so you can fit them into the bulb holder in 2 possible ways. My bulbs would work just as well in the USA if I just removed the bulb, turned it 180 degrees and put it back. Then the dip LED would shine left and there would be some bias (though not much) to the right - the nearside in the USA.
It sounds iffy, but we are not talking 21st century optics here; just a simple parabolic reflector (in OK condition) and the fluted glass 'lens'.
It is much much better to drive and I don't believe it dazzles others.
If you modified the holder so that the dip shined up and the main shined down, you would just get a vertical dip. Note that dip is half the brilliance of main (but still much better than 6v tungsten).
I see about four issues here:
1) filament orientation to the reflector & the road, yes needs to be correct
2)LEDs do not send light out in 360 degrees like a filament , so need to be correctly oriented, both to the reflector and to the lens (multiple LEDS)
3) LEDs will require much less Amps, a good thing!
3) rope seal, yes, the gap should be at the bottom, but it only needs to be 1/16" to 1/8" not one inch! You want enough to let any water out, but you also want to keep dust and excess air out, especially if you have silvered reflectors with no Pyrex overcoat.
This brings up 4) Reflector finish. Chrome is a lousy reflector, providing only about 60% or less reflectivity; this is why it was/is outlawed as a reflector coating in many states (An old law that pre-dates the development of the sealed-beam headlight bulb; which was such a safety improvement that it was quickly standardized nation-wide in the USA). Silver reflects about 96% when new, but quickly oxidizes to somewhere in the 80% range. The modern aluminized, Pyrex coated reflector surface reflects 92% and doesn't deteriorate. This is an important factor if you drive at night any.
Long-range, I see a correctly-made LED bulb matched with good reflectors as being the answer to good headlights.
The idea of making an altered socket to work with the wrong-oriented bulbs one way of "living with what is available," but it's a backwards way of "fixing" something that should be fixed at the source (bulbs!).
If these are as good as claimed, and I have no reason to believe otherwise, I will not be long before someone in North America like Don Lang will be making them available (I hope). Bruce