The Stovebolt Site Forums The Shop Area Paint and Body Shop Welding

Here's a sneaky trick that's worked well for me when I'm installing patch panels. Fit the patch as close as possible, of course, but if there's a little bit of a gap, go to the local big box hardware store, and buy a section of rigid copper water pipe, maybe 1" or larger in diameter, and 3 or 4 inches long. Cut a slot in it, and use a BFH and an anvil to flatten it out into a good-sized sheet of copper. Clamp this behind the gap. Now, when you stitch up the hole, there will be a layer of copper behind to keep the weld from blowing through. The wire won't burn through the copper- - - -it conducts the heat away too fast. Do a bunch of short tacks, and the back side will lay out smooth because the melted steel forms itself to the copper heat sink. Works like a charm!
Jerry

Hi Jerry. What would be 'too big' of a gap?

Thanks for the pointer of the flattened copper

I just got my gas conversion kit. I'm looking forward to trying out the welder. What would be a good gas to use? Argon or CO2? Which is more economical?

Your gas supplier that you buy your tank from will give you the correct gas Doug. 75% Argon/25% CO2 is the most common all round gas and will give you the best results for short-circuit type of welding, which is what you will be doing on a restoration. .025” wire is the most common wire that you will use for your sheet metal welding and you will be able to ¼” together with but would be better off switching to .035” wire for any of the heavier jobs.

Not relevant to the sort of equipment that you are using but just in case your interested in adding to your knowledge base; 100% CO2 is used for globular transfer (mode is rarely used) and it will give you deeper penetration but creates a lot of spatter. The arc stabilizes as you add argon and is ideal for the short arc transfer mode. In industry where large clean spatter free welds are called for the mode of transfer is often spray mode. You can’t get a true spray mode when the CO2 concentrations are over about 20% and the most common gas’s used for the spray mode are 90% Argon/10% CO2 or 95% Argon/5% Co2. The spray mode requires rather large high-current industrial welding equipment so you will probably never see metal transfer in this mode.
Hope that
Denny Graham
Sandwich, IL

I use the combo gas and the thinner wire. My stupid mistake was not taking the time to make sure both metal surfaces are real clean and keeping the gap small.

Live and learn. Or cry alot.

I have heard that there is a MIG wire out now that produces welds that are easier to grind. Has anyone tried this wire?

Thanks. I'll go for the Argon/CO2 mix then. I need to find a couple of practice pieces before I cut open the door to weld on the new pieces. I'm really looking forward to this. I'm going to try the flattened copper pipe suggestion someone out there gave too.

How clean did you get the pitted metal? That seems to be the hard part to me? Did you have to treat it with something? How about removing the protective primer on the new sheet metal parts?

How much are gas cylinders anyway? I saw one at Northen Tool that was $209! Harbor Freight for $89 but it was Argon. Do they put Argon and CO2 in an ARGON Cylinder?

there is a straight Argon available, but the 75/25 should have a label that says "Ar/CO2" ... not cheap, the main cost being the initial price of the bottle, after that refills are much less, and if you have someplace around that does that you can usually buy the bottle from them to start

Bill

Fred, if you want a weld that is easier to grind, put less of it in there!
The wire you should be using is ER70S6 and that’s probably them most common MIG wire being marketed. That’s a mild steel wire and you shouldn’t have any problem taking it sown with a grinder.

The welding supply houses around here will not exchange a bottle unless it's got their collar on it, so I would pick out a local welding supply and buy the bottle from them. They can also suggest a size based on the amount of welding you plan on doing.

Straight Argon is generally reserved for TIG welding Bill, because it doesn't give you the penetration or arc stability that a CO2 mix will. Even when operating in the spray mode we us a 95/5 mix to stabilize the arc. And you are correct; Argon has gone up in price a bunch in the last few years and is quite expensive. And this is a good reason to choose an area where the air is still and to use the lowest settings you can get away with on your flow meter.
Denny Graham
Sandwich, IL

Just an addendum to the wire size I mentioned earlier: While I have and you can weld heavier plate with .025” wire, I did notice on one of Miller’s charts that they only recommend using .025” wire up to .050”. We all know you can weld heavier material then that with .025” wire but a new comer to the art of welding might want to keep to the charts to start.

I'm trying to run down a location now. I think everything here in Texas closes at 1200 on Saturday and is closed on Sunday. Harbor Freight has the bottles cheaper but I need to find a place that will fill any bottle. The only place so far I've seen that says they will is on the other side of San Antonio.

And that's a good reason not to get one of those tiny bottles Doug. Unless you're welding steady you will only need a refill a couple of times a year. A 125cf or 150cf bottle is about the most practicle size for the home shop. That should be about 7" in dia and about 48" tall.
I gotta drive about 30 miles to get a refill, just plan ahead a little.

Denny G

check the web Doug - around me places like industrial suppliers, farm supply shops and some auto parts places are bottled gas depots for the major gas suppliers

Bill

Something else you might do is check the want ads, pawn shops and the like. If you educate yourself on the cost of these things, and take your time you can get a really good deal. Last July I picked up a cart, cutting torch with hose and guages, and the gas bottles for $200. The bottles were the large size oxy and acetylene. The oxy bottle was about half full, and the acetylene was almost empty. The down side is it took me almost 2 years of biding my time to find this deal. Oh, I looked up the torch head and body, and while not a Victor journeyman it is the same size, and listed new for $160. Not bad if I do say so myself!!

I drove up to McKinney for my bottle. It is about 3 feet long and cost around $100 for the bottle and mix gas. Probably big but enough to last for my kind of work.

So, let me ask this, does it have to be a Argon/CO2 Bottle or, if I by a used one can it be anything? I assume it has something to do with the pressure of the gas and the type of fitting? I think a used bottle is more in my reach. I know they have to pressure tested periodically.

Yes any bottle will usually do. For example, when we have alot of TIG work we have the empty bottles exchanged for argon. And then exchange those expties for an argon mix when we are gonna be doing alot of MIG

I just didn't know if the actual bottle would make a difference. If I walk in and ask them to fill a CO2 Bottle with Argon/CO2 mix I don't want them thinking I'm a nut.

they don't 'fill your bottle while you wait', they sell you a full one of what you want and take your empty in return to send back to the gas plant, like a core charge - gas bottles are the same regardless, the labels are different, and here any percentage of Argon is in a blue bottle

Bill

Thanks,I guess I should've realized it works like a propane tank for the grill. I wasn't thinking about it like that. Now I'll try to find a cylinder at a good price.