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This question is not about my truck. She is 12 volt, alternator equipped and electrically OK.

I am building a portable, mechanical, 12 volt battery charger. I am using an old 12 volt Delco-Remy 1102096 generator. I noticed that the communicator in the unit is worn down. I was thinking about sending the armature assembly to the rebuilders, when I remembered that I had a clean, rebuilt, unused, D-R 6 volt generator for a White truck in my basement. When I compared the generators and looked at the communicators they appear to be identical between the 6 volt and the 12 v unit. In fact the gauge of the wires on the armature appear to be the same in both units.

My question is can I just swap armature assemblies, or is there some magic "Boss Kett" magic powder in the 12 volt unit?

I always thought that a generator will just start making volts on a speed dependent linear scale from 0 to 20 or so, as it spins. Therefore the 6 or 12 volt ranges were all set by the regulator and storage battery used.

The 3100 Rule,


As long as the commutator doesn't have any shorted bars, it can be turned down and undercut many times. I have seen commutators turned so much I wondered how the generator could 'gen', but it did so just fine.

I don't know this for sure, but if the 6 volt armature has the same exact physical dimensions, most importantly, the armature proper is centered in the field shoes, It seems it would work fine. This is a non-engineer, backyard observation though.

Interesting project..you must be part mad scientist too!


Stuart

I agree with "atomarc". Neat idea. How ya going to turn it? Water power or wind? Post a pic when you're done.
On a more serious note: Count the segments or bars on the two commutators. Is there not a different number? Also check the width of the brushes? Get back to us.

That is a good question Beltfed. I am using a 3/4 horse electric motor. I will take some pictures after it is up and charging.

The brushes look the same and the communicator bars appear to be the same number. I'll check, but I think that I will get the job done right and have the com cut down and cleaned up.

Why not hook the 6V gen up to a 12V regulator and see what it puts out?

Good questions, and answers here. My thought is: even if it is the same physical size, the number of turns in the commutator windings would likely be different between the 6v and 12v units.

Years ago we had a big generator mounted in a kids type wagon we used for starting big trucks. We had a 5 horse gas engine on it & when you hooked it up it would slow that engine way down & it would labor & ping. 3/4 horse won,t do it. Why not use an alternator. It has more power & will not destruck itself if allowed to overcharge.

Well Wrench I was considering using an alternator until I noticed that all of the one wire jobs, as well as the stock wire set-ups, all required a working live 12 volt battery to tickle the alternators innards and make them transform motion into electricity. A good old fashoned generator did not require that kind of excitement. As the original purpose was to charge a dead battery, I thought that a modern alternator was out.

I have created a pulley transmission between the 3/4 horse motor and the generator. Sheer mad science just may make this deal work.

Man, this is a great thread! Some of us don't got enough to do!

Go to mine E=I over R if you want to see an electrical situation.

Hey, this is a cool concept.

Let us know how it works out... and maybe write up a tech tip... you know, if you wanna...

I am new to this picture thing, so I set up a page on MSN just to share this mad science project with the Stovebolt community. I have the first two pictures up if you want to see them. Here is the URL:

http://wrlynch.spaces.live.com/

The transmission is a 5 speed. It can be belted from about 575 RPM's to about 3,580 RPM's. Once the generator is on, I should have a good range of torque and speeds to find the sweet spot for making 14.5 volts and 20+ amps.

You are right about needing to energize the field. I don,t think a 3/4 horse motor is going to generate 20 amps. Why not use a gas engine so it will be portable. If you are going to plug it in any battery charger would work. I,ve got a couple of big H.D. generators out of a Start-all. The cost of shipping would be prohibative.

Wrench, I have come this far on electricity. If the amp meter shows that a faster spin will do the trick, I will try a new and improved gasoline powered version.

I know what you mean about using a conventional transformer battery charger, but it seems that every time I need one it has died. I had just purchased a new Schumacher charger in Oct. of '06, and it died on the second use. It has been sitting at the Schumacher factory for 20+ days now waiting for a repair. I just got fed-up The last charger only lasted about 6 years or so. In the meantime, these generators, electric motors and voltage regulators have been around for decades with no sign of croaking out anytime soon. It just made sence to me to give it a try.

You guys seem to think this is a new idea. This is the way chargers were made in the 40s.

We have a new Schumacher too & i don,t like it. It,s all eletronic & digital. It cuts itsself back when you want it to keep charging.

Thanks Cletis! I had no idea that it was a 1940's device. It seemed too simple an idea to be an original.

Wrench, just wait till it needs repairs! You have to send it to a po box in Hoopeston, IL. I sent mine certified mail, so I know that it arrived in the po box 21 days before they even bothered to pick it up. I have no idea when they will repair it, or even bother to send it back. Either they are swamped with bad products, or they are totally messed-up or perhaps it is a combination of the two.

Wrench,
I take it back! After a month of waiting, Schumacher just sent me, via UPS, a brand new battery charger. It appears to be improved over the old one as it has a better switch to click among the charging modes. Time will tell. I am still building my 1940's generator charger. More details to come.

The 3100 rule.You really have to much time on your hands. JUST KIDDING

This is a bit of a sidetrip but I have to ask. Reason being that I have a vintage travel trailer that will eventually require a deep cylcle battery and the transformer/charger seems to be working fine. Question is, hasn't the battery charger been around forever? And aren't they pretty reliable products?

Orchidskip, I have had conventional charges which have lasted 7 years or so. That was on the high end. I never dropped them, or kicked them around. They were always stored in a dry safe place. I never had long term luck with them. Maybe I should have parted with more cash when I purchased them, as I have seen the big shop chargers on wheels which appeared to be older than I am and still in service.

I just suspect that a pure mechanical charger may last longer in service and be easier to repair should it fail, than a transformer and a bunch of circuit boards in a box.

Yeah, I guess you get what you pay for. Not knockin' your plan in any event. I think it's worth doing if for no other reason than to learn something along the way. No reason why it wouldn't work. Let us know. Skip

I had a little 2/10 amp charger that lasted 15 years until i hooked it up to a six volt battery.

I bought a 53 chevy with a six volt gen and a 12 volt regulator that seemed to work as 12 volt. i used the gen as 6v on another car so don't know how long it would work.

Some battery chargers don't like small wire gauge extension cords or very long extension cords. Mine is well over 7 y/o, a Schumacher, I never move it, always plugged straight into the wall. I had a buddy go thru several chargers by using 200+ft of cord to start cars(too lazy to pull the battery out-but he does now). Brian

Actually they go bacl much further than the 40's.... As Briggs&Stratton built and sold a full line of what they called "Power Chargers" beginning in the 20's through the early 50's. They cam in a range of voltages (6v,12v,18v,24v,36v), and were powered by a 3/4hp engine direct coupled.

They were originally designed to be used on farms, back when most farms didn't have electricity. The farmer would use the charger to charge and maintain a bank of batteries that would in turm supply electrical power to the house and/or what ever else he needed. The voltage was dictated by what the farmer was operating as well as how far away he needed the electricity. When the REA came into being in the late 30's and rual america began to get electrified, alot of the old power-chargers were either tossed on the junk pile, or (for the 6/12v ones) relegated to the barn/garage as battery charger/jump starters for the farm equipment. During WW2 and Korea Uncle Sam saw a further use for these as field units for charging the battery on, or jump starting equipment in the field..... You'll notice that most all military gen-sets of the era (PE-73/PE-105 etc.) were also set up to not only provide 110v AC, but also provide 6/12v DC for radio equipment or battery charging as well.....

I happen to have one from the early 50's that is 12v and the output leads are HD cables with jumper cable style clamps on the ends. the unit even has gauges to show volt/amp output. Of course this one is painted OD green...lol

I also have several old 30's,40's gen-sets floating around here...lol

Just curious as I ran across a page that tells about using alternators to generate power and they say you can charge batteries or power an inverter direct with no batteries. I guess my question is how are they using alternators without a battery? I always thought alternators put out power no matter what?
Here is the link if anyone is interested.
http://www.theepicenter.com//tow082099.html

Some alternators will self excite on what is termed residual magnetism,but in just about every case when an alternator is "open circuited" i.e. the battery disconnected,the regulator has nothing to referance the output voltage to and therefore the output can for instance on a 12 volt unit end up around 30-40 volts,a 12 volt,80 amp alternator can be used as a welder but with a low duty cycle,that being infrequent use with extended cooling times but once again this is a very crude way of doing things.As one of the other members has pointed out they do take a bit to drive and this will increase with the load placed on the alternator,happy experimenting

When we did our conversions from 6 to 12 V, most rodders would change the generator, starter, and voltage regulator, I remember asking the friendly old guy that ran the auto electric shop why not just use the 12 v regulator. His answer was that it could work but the 6V generator doesn't have as many windings in the field coils. and would require a higher rpm to put out the same voltage as the 12V design. So, it doesn't mean that it wouldn't work, but that you would have to turn it faster.
He was also the guy that told me to save my money and keep the 6V starter, it is wound with heavier wire and would work just fine. I never had any problems.
I have a dirt simple 12V plug_in charger that is still working for me (20 + years ) and I even use it to jump start my old Bob Cat loader. I even ran over it once, blush, and it still works.
Bob

I've been told by F___ folks that a 12V reg on a 6V gennie works fine, the gen doesn't know how many volts to make until the reg tells it... they usu do that on flatheads as alt conversion is (or was) near impossible

I've converted many of the old trucks to 12 volts over the years and never changed out the 6 volt gen unless it was worn out. With a new 12 volt regulator properly polarized the 6 volt gen works fine. I've been told many times it wont work it don't work it can't work but I just say ok and go on about my business.

hi guys new to this site but just have a thought on this.the dc generator and dc alternator where never designed to recharge dead batteries.They where ment to supply power for the electrical system load after start up and replace power in battery used during starting.they where engineered to the amount of accessories on vehicle.the more current or amperage the generator produces the more heat it produces.if run uncontroled it will work until you let the smoke out and then you can never put it back in again. :confused:

starterman your on to it mate even the best wire wranglers have trouble putting smoke back in the wires most i know are good but not that good Remember if your meter becomes a motor your pointer becomes a pretzel. sparky talk for a u/s meter