I have often wondered, if there is some kind of voltage reducing device to cut the voltage from a 12 volt battery down to 6 or 8 volts, in the high amperages needed to start a T. ?? If so, are there any small enough to fit under the car out of sight. I understand reducing the voltage through resistance of some form, generates a lot of heat. So it also would need to be safe enough to use with out setting the car on fire. With 6 volt batteries getting harder to get, I would think some kind of device would sell well. I am not an electric Guru, but I bet we have some Gurus out there somewhere.
I haven't done this myself, but I've seen a bendix spring used as a resistor, mounted on the starter power post one end and the cable on the other.
I didn't think 6V batteries were that hard to come by, Die Hard has 'em, NAPA has 'em, I have one of those plastic red & gray gel type in my TT Firetruck..can't remember the brand at the moment, but remember reading about them being on the market...just keep looking Donnie.
On the other hand, my '12 is on a 12Volt battery and
never have had any trouble with it
some ww2 army vehicles had a 12 volt battery, needed for just the radio, with another lug sticking out of the middle for 6 volts to run the truck.
I do the bendix spring deal on one 12 volt car and it helps the starter not to kick as hard. Went back to six volt on other cars and like it better. If I need 12 volts for an accessory, I just plug it into the portable 12 volt jump box I bought at Harbor Freight.
It sounds to me like you're trying make a duck get down and walk on all fours. It might work, but might also not be the most elegant choice. Mac's has a 12-volt starter for $275.
Considering the price of things nowadays, that's not outrageous. Maybe it's the way to go? I have one in my Flivver and it starts the engine like crazy.
Optima is brand name Tim is thinking of. I have a 6V Optima gel battery in my speedster. It works my lights and aholga horn great.
Using a resistor is a fallacy as voltage drop depends on current drawn by the starter motor. This in turn depends on the load of the starter - which is not constant.
High current MOSFETs driven by a switchmode regulator would do the job, providing a regulated 6V to the motor with hardly any heat dissipation.
6V batteries are far from hard to get. Electric forklifts are going to be around for a while yet, and that's just one modern use they're made for.
If a 6V battery needs frequent replacing, some kind of electrical or maintenance problem is evident. I got 10 years out of my last one.
I have heard of rewinding the 6 volt starter, it might be just putting windings in series instead of parallel. Someone with experience would be able to help you do it.
However, unless you have some other reason for using 12 volts, you can just continue to use 6 volts. they are not hard to find. Last March I was in Sierra Vista Az and neededA a new 6 volt battery. I called the local AUTO ZONE. It was the first parts place I called and they had one. I went down there and it had a tag on it that it had been manufactured in February 2014, so it was almost brand new from the factory. I have also found them at NAPA, and and PEP BOYS Others have posted that they find them at TRACTOR SUPPLY.
Dont ask me specifics on this... but I was told you can coil up 15ft or so of wire under the seat before it goes to the starter. This drops the current down.
Years ago I "converted" my 26 to 12 volt and promptly broke the bendix spring. Then I broke another and another. Finally, I mounted a bendix spring in series with the starter lead and haven't broke a spring since. That was 20 years ago.
Some say you will eat the bendix often, others say they have used 12 for years without an issue.
Personally I am going to use 12 volt not because six volt wont work but because in todays traffic I want the best lights I can get and almost all modern equipment works with 12 volt. Becker was selling 12 volt alternators and starters for 145. as I recall.
Im was just interested to see what options are available. Ive see the diagrams to rewire a 6 volt starter to make it a 12 volt starter, Its not really that hard to do, Ive also heard of the bendix spring idea. Macs has the 12 volt starters. They do not look like an original T starter but are close enough to not be noticed. The high current MOSFETs driven by the switch mode regulator sounds interesting but way over my head ...... Ill probably just use a 6 volt battery and buy an inverter later to run the cell phone when on long tours ... or I could buy the 12 volt starter and not need the inverter, choices, and choices, and choices .....
Paul. The 12 volts for the brighter lights is also one of my concerns ....
I've had a 12v in my TT for 14 years and only broke one spring, however, I did nothing to the generator and it slung the winding out of the armature which caused the steel gen gear to stop while the fiber timing gear continued. Made me glad I had a fiber gear rather than steel!
I ordered a 12V Fun Projects regulator from Lang's today to use for my Hack (no magnets). That seems to be the cheapest way to convert to 12 V.
The problem I've come across in using 12v, is the splitting of the paw drive for the bendix head, I've never broken a spring. An 8v dropped in works good for me and don't have to change globes or gen setting. (As yet)
Mike: You made me think again. Twice in one day may be a dangerous thing .... I have heard that it is OK to run a T generator to charge a 12 volt battery. But it will charge at 1/2 the rate. (takes twice as long to charge) Does anyone know if that is true .????
There was a post that recommended using 50 feet of number 8 copper wire between the starter switch and starter on a 12V system. I have the wire but have not installed it yet.
#8 wire is rated for something like 40 or 50 amps. Sounds more like a fuse than a starter cable. Yeah, I know it only sees the current for a short period of time, but still......
6 volt batteries are not hard to find. I live in what most would consider a small town. I could find a 6 volt group 1 in probably 3-4 different places on any given day. One thing leads to another. Somebody feels the need for a 12 volt, but then they have to find ways to keep from ruining the starter. Then how to charge it. No problem, install an alternator. But wait, I don't want it to look like an alternator.......And so it goes. Good source of amusement, though.
Do what you will to yours, but mine does just fine on 6.
You don't need an 'inverter' to power a cell phone. Most phones now charge from USB which is 5V at 0.5-2Amps. I used a DC to DC bucking converter to drop 6V to 5V at up to 3Amps of power. More than enough to run any device that needs usb power.
Its also really easy to go the other way if you pick-up a DC-DC boost converter. Just make sure to watch your power draw so that the design limits of the converter aren't exceeded.
Headlights are another story...
Simple fix, just drive your modern car and you will have all the 12 volt power you need! KGB
Any farm store will have six volt batteries available. A lot of farmers are still using old tractors that run on six volt systems.
That being said, it might not hurt to have a backup plan for if and when six volt batteries become hard to find. Maybe it's the prepper in me coming out, but it would be handy to know I could convert my car to 12 volts if needed.
If brighter headlights is the only reason you want to switch to twelve, what about LEDs? Is anybody making 6v LED bulbs? That seems like a much simpler and most likely a cheaper solution than replacing a battery, regulator, and starter.
I have no problem getting 6 volt batteries problem is someone had already converted my car to 12 volt and had no resistor since the starter is designed to be a slower reving 6volt even though it has been "wound" for 12 volt nobody changed the bendix to account for higher "kick in" forces so I broke 2 bendix springs before I took 10 ft of 4 ga. copper wire and wound it around a broom stick to make a resistor to soften the blow when the starter engages. Now if I could just teach the "Kids" that install batteries that my '46 Plymouth is 6V POSITIVE GROUND oh! I'm sorry that is a topic for another forum.
It is fairly easy to modify the Model T 6 volt starter to run on 12 volts.. The change involves rewiring the two stator coil to be in series rather than in parallel. If you poke around the web you can find details or send me a PM. The Model T generator can reliably put out 72 watts, so at 6 volts you can set the third brush to generate 10-12 amps. For a 12 volt system then the output must be reduced to 5-6 amps which is marginal. For my customers who want 12 volts, I recommend an alternator.
I think what you mean by "resistor" Is inductor, or induction coil. The resistance in the copper wire is not what slows down the kick, but the surge of current going through the coil causes inductive reactance. Once the current flow stabilizes, it becomes 12 volts.
Sorry Norm I'm not an "Lectrical" genius I just called it what I thought it was all I know is it works it's been 2 years since I broke a spring
If you use a 6 volt system for your T and need to connect an iPhone cell or ipad, simply go to Monoprice.com and order a #10071 car phone charger and 12 volt female receptacle. Most car chargers will work. I am currently using the 10071 to charge my iPhone 5s for a GPS speedo. This is the Best and the least expensive site for cables also.
By the way not all 12volt car chargers will work. The cost of all except the USB cable is less than 25 dollars.