DIY Homebuilt Battery Booster/corded jump box

[2stroked]

Well, my dumb ass left my lighting turned on on the Cyprus yesterday, an woke up to a dead battery this morning. The lights are operated by a separate switch, and are unfortunately independent of the ignition.

Anyway, I went and grabbed my charger plugged it in and nadda. Nothing. It was dead. Well,at this point I was rather pissed off, an I am broke at the moment, so no buying a new charger today. So, I figured I would make one.


I had an old MOT ( microwave oven transformer ) that I was saving for a DIY spot welder build. So, I cut the secondary windings off and using a long piece of 10 guage house wire, I wrapped a new thirteen volt secondary. Now that primary is also ten guage, and has one hundred an twenty three wraps so that makes it ABOUT one wrap per volt. After wrapping the new secondary, I soldered a home made bridge rectifier, using four 1N5401 rectifying diodes, and attached the new thirteen volt AC secondary to the inputs of my new bridge, then attached the charging cables to the output terminals of the bridge. After checking the rectified voltage, it was jumping from 12.9-13.2, so I found a twelve volt regulator chip, and hooked it after the bridge an before the battery.

After a few safety checks I hooked the new charger to the totally dead ( 8.? Volts ) battery,waited fifteen minutes, unhooked the charger, and started my scoot. IT WORKS!!!!!!!!!!! Ugly, but functional, I like it.

I am going to order some better diodes, or perhaps a modular regulator rectifier unit. As well as a voltmeter. The current bridge is getting slightly warm anits in a dissipating silicate sand, so I went and wired a cooling fan with a blockingdiode, so the an voltagf comes from the charger, and not the battery.

[ryan_ott]

Awesome love home brew electronics. My dad was a electrical engineer so we always had "fun" stuff around. I still have a bunch of chargers he built that still work. Props to you!

[niz76]

Nice! I built a homemade DC battery charger for my 60v electric scooter. It was pretty simple since I didn't need a transformer. Just a bridge rectifier a big capacitor from an A/C condenser and voila! 60 volt onboard charger! It pushed about 3 amps or so. It worked perfectly to charge the scoot overnight and all fit nicely onboard in a small tupperware container.

[dan50]

Good Old American Ingenuity!

[2stroked]

Thanx guys, I just like to build things. I would rather build something than buy it, if that makes sense.

I have plans for a stick welder, a spot welder, and even a plasma cutter. The two welders will each use two MOTs as a power source, the plasma cutter uses, believe it or not, a television flyback transformer, and a GM coil and HEI switch as it's power source. I am a bit Leary of the plasma cutter build, due to the extreme voltage therin.

I am going to order some bigger diodes and or maybe a full wave rectifier. The diodes that I have now are getting a bit hot during charging. Thought of trying to find a modular regulator and rectifier, but IDK.

[FrankenMech]

You did good, kudos for ingenuity.

I am thinking about tapping off the AC output side of an old rebuilt 20-40/250A 12v battery charger for a spot welder. I have an old microwave, I may have to investigate it also...

Buck converters are fairly cheap on ebay and Amazon if you eventually need one.

I save my old style transformer type wall wart chargers to make battery eliminators and trickle chargers out of. I buy some at garage sales or Goodwill etc also. I also save the new-style switching power supplies. I am using one on my scoot battery.

I admit I am somewhat of a hoarder...
Mad scientist too, I have a periodic chart on the wall, Four Halloween skulls on the bookshelf. Hundreds of reference books and manuals, some goofy lights, and radiometer. Boxes of junk.

To invent, you need a good imagination and a pile of junk.
-Thomas A. Edison

I am thinking about getting one of those lightning balls but they cost $$ and don't have a good lifespan. Maybe a lava lamp too sometime. Building a Tesla coil...

[renagade281]

May 22, 2016 21:30:17 GMT -5 2stroked said:

Thanx guys, I just like to build things. I would rather build something than buy it, if that makes sense.

I have plans for a stick welder, a spot welder, and even a plasma cutter. The two welders will each use two MOTs as a power source, the plasma cutter uses, believe it or not, a television flyback transformer, and a GM coil and HEI switch as it's power source. I am a bit Leary of the plasma cutter build, due to the extreme voltage therin.

I am going to order some bigger diodes and or maybe a full wave rectifier. The diodes that I have now are getting a bit hot during charging. Thought of trying to find a modular regulator and rectifier, but IDK.

Im assuming u will need to hook it up to an air compressor?

[FrankenMech]

Air compressor... Who needs an air compressor? Just eat lots of beans.

Are you finding plans online somewhere?

[renagade281]

Lol no. I use a plasma cutter at the shop all the time and they usually have to have some kind of high pressure air going thru them right? Idk alot about home made devices

[2stroked]

Yes an air compressor will be needed. The plans are from several sources and what I have done is to pick the better points of each and form my own design. Google " The Plasmanator " and you should find one if the more basic designs from instructibles.

I have two separate air compressor pumps, from old home oxygen machines. They can handle a sustained 80psi from expierience. I just used an old air tank like the old tire tanks without a pump, and built a small rack onto it to mount one of the compressor motors, and plumbed the air into the tank. Easy Peasy!


I am ALWAYS looking for new projects, and new " junk " for parts and supplies.

[2stroked]

Got my hands on an old atx power su0ly for an old tower computer today, used it as a battery charger/ trickle charger for the tractor. Its small enough to be able to bolt to the firewall beside the battery too. At least with that one, I know the exact voltage and current that's flowing at all times,no guessing.


Thought about replacing the magnetic shunts in the charger I built. They are there to choke the current kinda and to keep things as even as the can. Far as I can tell, they are almost useless. Found a medicine bottle full of old 1N5404 diodes this evening, thinking of using eight of those and building a full wave rectifier that can handle more than the charger puts out. I did use it on the old tractor battery this more ng, took twenty minutes from so dead the starter wouldn't even click, to full enough to spin the motor fast enough to easily catch. Nottooshaby for hand made.

[2stroked]

FrankenMech, these MOT's are extremely handy, I am finding new projects for them almost every day or so. Old flyback transformers from old CRT televisions are pretty cool too. I have the plans for a Jacobs ladder eight feet tall that uses two fly backs. I don't think I will ever get around t building that, a little to dangerous.


If you look, you will probably find plans for a lightning ball. Static electricity isn't that dangerous, and can easily be harnessed. Tesla coils are a fun project as well, and can also be built using recycled flybacks.

[FrankenMech]

You know the condition my hands are in. I still keep collecting parts for projects though to keep the mind active. I have several old CRT monitors and a TV, -more can be had on 'big trash days' around here. I can still kind-of take things apart, not so much on assy. I will have to look for microwaves on big trash day also. I am hoping to keep functional enough to get on Medicare when I reach 65 and maybe get some neurological help. That will take two years yet and prospects are not looking good for being able to last that long. I am flat miserable not being able to use my hands after an entire life using my hands to create, repair, and work on things...

Thanks for the plasma cutter place.

I did join the instructables site, not the pro version though. They want more for that than I pay for a half year of Netflix etc. I am trying to figure out a good user name. I spent money on supporting this forum instead.

A Jacobs ladder 8 feet tall would be fun. I have a good place for one where it would light up the neighborhood. I have a welder in that sunroom now that I have used in the past to freak everyone out. I am not afraid to build high voltage or power electrical devices. I had good mentors when I was young that schooled me well and a lot of OJT training and in institutions of higher learning. One of my childhood mentors built things like Tesla coils with a high degree of skill. I have designed, constructed, and supervised construction of motor control centers for 100's of HP, complex automation and machine control centers, instrumentation, along with many electronic power units, microprocessor controls, automation controls, and interface cards for use with PC's and PLC's when the right card was not available. After a few strokes I don't do that anymore. Scoot electrical systems are still extremely simple.

I have bought some high current and HV diodes and bridge rectifiers on ebay and amazon in the past for cheap. Singles are expensive, bags of 10-25-100 are really cheap. Procuring such parts are what keep me occupied and from going completely insane. Some call that 'retail therapy'. Some of the part electrical ratings are suspect though.

They're coming to take me away ho ho he he ha ha. To the funny farm where life is beautiful all the time, and I'll be happy to see those nice young men in their clean white coats...

[2stroked]

My Dad used to sing that song when I was a kid.

I had a long and thoughtful post, about our imagination, and the stuff we have built and will build, also about the hell of a neurological problem. I for real didn't think I would survive my issues, before we figured the magical medicinal combo for control of the shakes and shimmies.

Then my POS phone, decided to take a quief moment.......



Don't you qualify for that Obama care??? Seems everyone here in Kentucky has Obama Care, and most are healthy, and don't need the coverage. I do know, that when I was injured, and denied WC and TD, the Obama Care, picked up all the bills for my surgeries, and they are still paying for my Rehabilitation. As well as covering my medication, that damn Gabapentin is high as shit!!! 90 of them used to cost me 287 a month, plus the other shit I am on. Honestly, I would be SCREWED without it.


I wish we lived closer together, we could get into a lot of trouble, building that Mad Scientist shit.

[FrankenMech]

You and I could get in real trouble...

I used to sing that song. I used it for a ringtone for family members.

They have found no magical combo for my ET. It has also been over 10 years since I have seen a neurologist or heaven forbid, -a motion control specialist. The last time I saw a doctor was in 09.

I have difficulties qualifying for Obamacare due to some of my own neurological problems. I have never made it through the application process and the other paperwork and reporting requirements. I just can't hold form crap and instructions in my head. The memory and ADD are too bad. ET makes it damn impossible to search through files and physical paperwork. Healthy people are what Obamacare WANTS. They don't want unhealthy people. We cost too much even though my health issues are mostly genetic and a result of childhood disease that could not have been prevented at that time. Some may be aggravated by exposure to chemicals in the workplace.

I forget what my gabapentin costs. I only take 60/month. I only have 10 prescriptions I pay for and they run $70 every 4 weeks. I try to cut down. I have stopped taking some of the more expensive cholesterol stuff AMA since they are for things that won't kill me quickly.

I have two more prescriptions that I sometimes get for free (PAP) but neither of them are coming now due to paperwork problems. Samples of one are being provided by a county clinic but not the Victoza used for diabetes. Therefore my sugar levels are way high. The Victoza stuff costs around $500/month, it used to cost $1400/month. The company that makes it thinks Medicaid should pay but I am not on Medicaid. Catch-22, or a rock and a hard place.

Medicaid is called Kancare in Brownbackistan and NObody that NEEDS Medicare is wanted in Brownbackistan. Governor Brownback, his cronies, and his legislators are trying to force anyone needing Medicaid or food stamps or any other form of aid to leave the state. Unfortunately I am tied to a house here that is almost paid for and I certainly don't want to have to rent and be dependent on the whim$ of a landlord for the remainder of my time. Repairs, upkeep, and maintenance are a real pain with ET and little income but the income may get better for a few years. Eventually I will have to pay someone to do all the maintenance on the house, yard, scoot and cages.