LocostUSA.com

OK guys I've got the welder open and before I stick my fingers in there and get my gizzards fried, is there any place I shouldn't touch? I'm attaching several different shots of the internals to make it easy for you to warn me "There be dragons"

The issue is a non-continuous arc which I am presuming is coming about from some minor corrosion on some internal connectors caused by sitting unused since 1998. It was new at that time. Now if I turn it all the way up and the wire speed almost all the way down I can almost hold an arc. It's not inadequate 110V supply as I've tried it at 3 different locations, 2 of which already have operating welders using it.

I've already cleaned all the connectors I can get to without opening the cover so it was time to open the cover and delve inside.

I also need to change the gas connector out for a standard one so that I can use just any old regulator. Does your welder have the little plastic line internally like this one?

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

I was thinking there should be a large capacitor in there somewhere, but I don't see one.

_________________
Too much week, not enough weekend.

OOPS I did it again
http://www.locostusa.com/forums/viewtopic.php?f=35&t=17496

Blood Sweat and Beers
http://www.locostusa.com/forums/viewtopic.php?f=35&t=15216

Uh Oh, I'm getting the dreaded "Resource Limit Reached" and the intermittent connection to the forum.

I removed and then reseated the slip connectors on the voltage control to cut through any surface corrosion that might be present. I found one of the connectors wasn't seated tightly so I crimped it a little more and now it seats like it ought to. Could it have been as simple as that?

I still haven't touched any of the big connectors till I hear from you guys there's no residual voltage that will give me one of those weird Einstein type of hairdos.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

Yes I was too, but nothing there that I recognize as a capacitor. Without it I think I'm safe to go dicking around in there, but I want someone smarter than me to tell me that.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

Have you got a multi-meter? If so, go searching for voltage before you take anything apart.

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Bill H
Winnipeg, MB, Canada

I'd already done that, but I've found electricity can be sneaky and hide in places you don't expect it. Also we're talking some pretty big coils here so a surprise there might be your last.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

Carguy,
If it has been unplugged for a while and no BIG caps to be found, you should be good to go. The transformer should have no residual voltage.
Walt

Ok, but I'm going to tell all my future life insurance beneficiaries you said so. This way they'll know who to look to for food, shelter & clothing.

That loud buzz and light flash in the sky you guys will soon see will be me.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

EUREKA!

It works! Not quite perfect, but dramatically better than before.

I could not clean the largest wires because they were mounted on some kind of fragile standoff that wouldn't allow me to apply any pressure to remove those nuts so it's not perfect. But....I''m thinking that with usage it should take off, or burn through, whatever is on those and it will only get better.

I don't know if it was that one connector or the minor corrosion on some of the others or what, all I know is that now it works well enough to actually get some practice in.

Before if I turned it to 4 (the highest setting) it would maintain an arc about 1/3 longer than at the lower settings. Now at 3 I can get a continuous arc and run a bead. The machine says the setting ought to be a 2, but I can live with that.

Now to go buy some more of that .35¢ a pound steel to practice on and build some heavy duty roll around dollies for my big ass plants.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

That's good, making progress definitely helps point you in the right direction. I'd guess it's the loose connection you found.

Does this welder not have a circuit board of some type in it?

Ideally electrical connections should be gas tight. That prevents the corrosion. It's done different ways, but on power circuits you should see things like star shape lock washers with sharp edges. This is critical in electronics circuits - things with transistors and low voltages and power. The connectors you fixed use the edges of the sliding part to scrape to clean metal.

Now that you have got this far want to buy a capacitor and install it? We had that described in a thread somewhere in this forum. My Lincoln 180 has one, they seem to leave them out of the lower power and lower cost units.

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

No circuit boards, except for on the rheostat of the wire feed.

The wire connectors were of the split washer variety and the bigger wires are just bent around a bolt. These were the ones I couldn't get off because of how the piece they are connected to is mounted.

The capacitor benefits me how exactly?

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

My local welding store has the brass pipe fittings.

What were looking at is the things you need to do to cost reduce a welder for entry level people. Working after 10 years of being idle probably isn't on the list. Mind you the engineer put it on the list but his manager said "no you ignorant slut!". My 175A welder has different part numbers when sold by Lowes, Home Depot and my local welding shop. Guess which one costs the most but has the metal feed mechanism for the wire...

I didn't see the wire wrapped around bolts, that sounds a bit marginal. It wouldn't hurt to add a star washer but I wouldn't mess with things that look like you might break them. It's cheaper that way, but a swaged lug on the cable makes a gas tight joint and the lug makes a good place for a washer that does the same. I saw a wire nut used in one of your pictures and they also make gas tight joints where the thread cuts the metal. That's why in electrical stuff you should replace the wire nuts and washers if you take it apart several times while you are debugging them.

So what your looking at in that box is a big transformer on the left side. It converts your high household voltage to a lower voltage with a lot more amps. In plumbing terms it would make a high pressure to a low pressure with a lot more volume to it. The high pressure is good for moving long distances, like from a power plant to your house.

On the right side of the big metal piece is another wire winding that is an inductor. We are considering adding a capacitor. These are both energy storage devices. The inductor will try to maintain the voltage or pressure. It's a little harder to imagine as plumbing, but think of a long pipe and the momentum of the liquid inside of it. You won't be able to change the rate of flow until you do the work to change the rate of all the weight in that pipeline. Imagine shutting off a 100 mile long oil pipeline quickly. A capacitor stores charge like an Accusump would do for an engine. Think of a ballon or rubber diaphram that stretches.

Used together they will provide the most stable arc. A capacitor is not expensive but more then the turns of copper, so that's why it's missing. The power coming in is AC, since that is alternating current, it also implies it's no current at all 120 times a second. The capacitor will allow more current to flow thru the transformer when it is available and supply that while the input current is alternating ( no current ).

This is simplified the affect at the arc can be to make more energy available for short bursts to vaporize the wire.

In real life the engineers at these places design this stuff for the materials being worked on, the skill of the users and the applications. Then their manager says "no you ignorant slut". Then some in production or an accountant finds a way to save 3 cents, which will allow someone in upper management to add the letters AMG to his Mercedes. The last 3 cents comes from using washers made from powdered rust manufactured in Burma.

So there you have it!

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Arc stabilizer, I like it.

I'll have to do a search for that thread and see what kind/size of capacitor and where to wire it in.

This will give me a chance to clean the other 4 wires since I'll have to break the mounting bracket to put on the capacitor so I can put new ones on and clean those connections all at the same time.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.