I never got more than the 4.5" guard. I got the early version with the regular slide button. They make a trigger style one now I think.
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I used to buy Dewalt right-angle grinders and the extra warranty when I had my shop and used them daily.I kept 3 grinders at my workbench so that I did not have to change from a grinding wheel, to sanding disk, wire cup, or what ever so often. I was using them in my business and this saved time. the one year standard warrenty, plus the the second year usually extended some of thier lifes, so it paid off. I still have a couple now that I am retired.
kent
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Has anyone ever come up with a current limiting device for stick welding with batteries? I was welding the form rebars together with the electric gulf cart, and started thinking about this again.
Could a LiFePO4 BMS be made to work?
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The BMS will probably not be a suitable solution, since it is a system for controlling the voltage of an individual cell and thus regulating the charging… I think that this could be done with a minor modification of the inverter welding machine, since it charges the power capacitors according to the PWM process and maintains a low voltage for welding. How much voltage do you have on the batteries?
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I have four 12vdc batteries @100ah capacity. I welded these bars with 36vdc and no amperage control. It was a bit hot.
In the past I tried electrodes in a pail of water, and having a battery with a dead cell in series.
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Thats what happens some times trying too get more done than you have time for, Though i usually only chop one out of three wires, and hot welding spratter sparks burn down too the wire some times, Good luck with your replacement wire.
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This is from a book called " do it yourself 12 volt solar power."
"Car batteries can easily give out up to 300A, But that’s more than you really need to weld. The electrodes would get too hot and the welding area too big. So you have to bring the current down with a simple resistor of fence wire wound around something heat resistant and non conducting, like a brick.
Iron fence wire regulates the current perfectly. If it’s cold it lets all current flow, but if it gets hot the resistance increases very quickly and it regulates the current down. For electrodes with 2 to 2.5mm dia. use 6m of 3mm fence wire.The exact length varies with the age and capacity of the batteries and the current you need for welding. Make some connection points on the fence wire at say 10cm/20cm/40cm/80cm/1.5m/3m/6m/, then you will always be able to set the right current.
I don’t know if that’s any use to you Bruce. There are some small diagrams. You can get the book on Amazon. There are other sections about converting other tools to 12V.
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Yes, what Tom said. Resistor. The fence is a nice diy solution.
Bms wont work. Most will just cut of everything if current is to high. See it as a safetyswitch.
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A resistor to reduce the welding current is a solution, but a lot of energy is lost in this way, a much better solution is the PWM mode, where the power electronic switch allows shorter or longer current pulses and with this the input energy for welding is controlled, this is how newer welding devices work. I could use a classic PWM regulator, which would open a power thyristor,… or a transistor.
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Not sure if I understood Tom perfectly, but steel can be used as a low value resistor. One could move the ground clamp, on the work piece, closer or farther to the weld. This will allow you to fine tune the amount of current.
Rindert
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That was a quote from the book Rindert. My own knowledge of such matters allows me to reset a breaker. I just collect information on various means of self sufficiency.
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Argh! I actually have a 15A, 6, 12, 24V battery charger. I could get two car batterys and 20ft 10ga steel wire and make a very effective DC stick welder.
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Erma Gerrrrd! Rindert! I think you just described the speed control for the Melex golf cart. I should try those speed control resistors.
@Tone I wonder if the pwm golf cart speed controller could power the stick welding? I am not going to lose $250 on a blown controller to find out though.
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LOL. I have no idea what that means, but it sounds really cool. 
Note: I never said this thing would be efficient, only that it would work. When you charge a lead acid battery you loose about 30% of the energy to heat. And when you discharge that same battery you loose 30% of what you put in. .7x.7=.49 You get back about half of what you put in.
However, the very fine current control this would give you might help you weld very thin material.`
Rindert
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When making these resistors and coils, don’t you have to use insulated wire, so they don’t just short across the wraps? TomC
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Bruce, I don’t think a PWM controller from a golf cart can handle that much current.
Tom,
I don’t suggest you actually do this, except maybe as an experiment or a learning exercise. Here you can see how I have laid out 50ft of steel wire and connected my Ohm meter to it at two points. The wire is not touching itself anywhere. This is a very basic sort of rheostat. Something like this might actually work, but it would be a PITA to work with. If you were going to actually use something like this, I think you would want four 1x2" pieces of wood with notches cut in them and the wire wrapped around to form a regular sort of cage.
Rindert
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Thanks Rindert for the picture. That confirms my understanding of coils and rheostats. The other day I needed a 2 ohm resistor for a project. I took my ohm meter and set out measuring the resistance in every piece of wire in my shop. For the project I didn’t have the luxury of a room as you have shown. I had to be able to stuff it into a quart jar. Had to shelf that project. TomC
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My 2003 Dodge Ram came up with a code P0441 evporator bs stuff, I just clear it when it pops up every once in a while.
So checked my system hooked up my Eliti Auto Scanner tool made by Actron. Just too look at what my engine was going fuel trims , O2 , and the like. Looking at my timing adv. As I run the engine speed up and down and noticed the highest I could get it to change was 32° advanced. Humm. It should beable to go higher then that I was thinking.
So I hook up the scanner to Dana’s 2001 Subrau Out Back 2.5 L 4 cyclinder box engine. Ithad the same code to clear P0441 evpor. Cleared the code. Running engine speed up and down I noticed something the advance would change from 12° to 48° , well the computer system has a lot more range built into it. This little Out Back gets good gas mile over 27 mpg. On long traveling trips even better.
I have a 1996 Subrau Out Back that I am going to check it advance degrees out .
So if a engines computer system can change it’s advancement to over 48 ° just by reving up the engine you should be good to go running a OBD2 system on wood gas. Do you thing?
To hot now for me to check this out it is 105° f in the shade. Sitting here siping on some southern style sweet iced tea. Sweeten with honey is the way I like it.
The honey in the jar is 6 cups. It came from just one of frame out of the bee hive. Thank You Yehovah’s bees. And thank you Dana for the fresh baked bread. Yummy. Are you smacking your lips yet?
Bob
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Well ya! As i sit out of the 85* heat in my ac office drinking cruddy Arizona sweet tea from a can…
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