On board welder
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onboard welder
I Have an onboard welder in my BJ70. it really works well.. in fact i can blow a 5/32 rod through 3/8 plate no problem. also i have tig welded with it a few times. Its a real joy to have in there and ive used it many times.
my welder is completely homebuilt and it resides where the a/c pump would sit on the 3b.
im thinking of making brackets and selling them with the alternator if there was any interest.. the lead time would be around 1 month once i got the cad drawings made.
my first prototype would be transferred to CAD and i would make the dimensions or a pre made piece available.
as far as the alternator welder goes internally, it has twelve 50A diodes in a custom heatsink as well as a custom wound stator.
I should tell you, a fellow amateur radio operator designed and built this alternator.. he has retired and has a few of these welders still in service around the area with satisfied owners, hes not building them any more but i know that i could definately take up the slack since he has retired.. in fact, the old guy is not in the best of health and if i really made any profit off of these it would only be right to give back some to the original designer.
anyways... we shall see how much interest this post generates
I Have an onboard welder in my BJ70. it really works well.. in fact i can blow a 5/32 rod through 3/8 plate no problem. also i have tig welded with it a few times. Its a real joy to have in there and ive used it many times.
my welder is completely homebuilt and it resides where the a/c pump would sit on the 3b.
im thinking of making brackets and selling them with the alternator if there was any interest.. the lead time would be around 1 month once i got the cad drawings made.
my first prototype would be transferred to CAD and i would make the dimensions or a pre made piece available.
as far as the alternator welder goes internally, it has twelve 50A diodes in a custom heatsink as well as a custom wound stator.
I should tell you, a fellow amateur radio operator designed and built this alternator.. he has retired and has a few of these welders still in service around the area with satisfied owners, hes not building them any more but i know that i could definately take up the slack since he has retired.. in fact, the old guy is not in the best of health and if i really made any profit off of these it would only be right to give back some to the original designer.
anyways... we shall see how much interest this post generates
mk1pickle, sounds like a good idea. I would like to have an onboard stick welder. But my problem is I have an onboard air comp instead on my 3B. so I am running out of space for another alternator.
Although I could run it off the york. But an alternator like that needs a could belt running it.
Although I could run it off the york. But an alternator like that needs a could belt running it.
the welder that i have has rewound internals and 12 x 50 amp diodes and can push 300 amps at 30volts.
its not a regular alternator
you might get 100 amps out of a regular alternator, and it will have a poor duty cycle.
if you want to try building your own alternator welder.. go for it.. but remember that the open circuit voltage of an unregulated alternator used for welding is high voltage wich adds a safety issue to actually using a welder as an alternator without rewinding it and having a proper regulator.
its not a regular alternator
you might get 100 amps out of a regular alternator, and it will have a poor duty cycle.
if you want to try building your own alternator welder.. go for it.. but remember that the open circuit voltage of an unregulated alternator used for welding is high voltage wich adds a safety issue to actually using a welder as an alternator without rewinding it and having a proper regulator.
I have used a 105 A large case Ford alternator a la Jeff Fretwell "option 2". I only use it for trail emergencies.
Wiring is drop dead simple: I just run a jumper wire from the field terminal of the alternator to the battery + post and use jumper cables as the stinger and work piece leads. Disconnect the jumper when you are finished welding. Welding power is regulated by engine RPM and it needs to run at least 2,500 RPM.
I have run 3 3/32 6010 rods in a row without burning it out, so the duty cycle is good enough for any trail repair you are likely to encounter.
The OCV can exceed 120V DC, which is enough to run brush type power tools and it can give you a good buzz. The OCV on my Linde Heliarc welder is about 90V, so it can give you a buzz too.
These alternators are $15 in the junk yard. I tried rewiring the stator on one from Y to delta configuration to bias it to current production, but it didn't seem to matter noticably for welding.
Wiring is drop dead simple: I just run a jumper wire from the field terminal of the alternator to the battery + post and use jumper cables as the stinger and work piece leads. Disconnect the jumper when you are finished welding. Welding power is regulated by engine RPM and it needs to run at least 2,500 RPM.
I have run 3 3/32 6010 rods in a row without burning it out, so the duty cycle is good enough for any trail repair you are likely to encounter.
The OCV can exceed 120V DC, which is enough to run brush type power tools and it can give you a good buzz. The OCV on my Linde Heliarc welder is about 90V, so it can give you a buzz too.
These alternators are $15 in the junk yard. I tried rewiring the stator on one from Y to delta configuration to bias it to current production, but it didn't seem to matter noticably for welding.
Charlie- So engine RPM regulates current, and field regulates voltage, so can't you put a rheostat in the jumper wire to accurately control voltage? (primarily to limit voltage to 120v for incandescent bulbs and brush motors)
Both the field current and engine RPM regulate alternator power (amps x volts). The voltage and amps depend on the load: low load = voltage high, amps low. high load = voltage low, amps high.
You can put a rheostat in there if you want, but I don't see the point in running the engine any faster than you need to just so you can turn the power down with a knob. You need to have a way to control the engine speed anyway, so you just turn up the speed until you get the voltage you want depending on the load. It is kind of cool running your grinder at 150 V.
You can put a rheostat in there if you want, but I don't see the point in running the engine any faster than you need to just so you can turn the power down with a knob. You need to have a way to control the engine speed anyway, so you just turn up the speed until you get the voltage you want depending on the load. It is kind of cool running your grinder at 150 V.
I know I am resurecting an old thread but can any one tell me what year the ford alternator would come off from.
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Both the current and the voltage are unregulated....you're essentially de-regulating an alternator. The faster it spins, the more output it creates limited only by it's own design potential. When the circuit is open, voltage goes sky-high. When the circuit is closed, the current goes high and the voltage drops to about 20 to 30 volts.
What's happing is instead of the regulator rapidly switching the field current to the rotor to average about 14 volts, short the regulator, or full-field the alternator providing constant current to the rotor. This give you unbridled current and voltage which can be used for welding, running brushed power tools, or stopping your heart! It's a concept dating back to the fifties or sixties and you can whip it up in your garage, buy it in packaged form under the name of Link-Arc, Resco, Thunderbolt, or Premier.
The MOBI-ARC Control unit uses a much different technique to create voltage and current from an alternator using state-of-the-art solid-state circuitry, and does so in a way that limits both current and voltage thus making the concept safer and more reliable. It's the difference between a hot-wired alternator whipped up in one's garage, verses a professionally engineered and patented unit like MOBI-ARC.....but I'm biased.
Scott