Gas welding

dhutton01

dhutton01

Backyard Hack
Because I have no conscience I like to murder at least one new skill per year. :D This year I’ve decided to attempt butt welding panels with an oxy acetylene torch. I got a torch setup from Dagger Tools and watched a couple of YouTube’s. Big Dave also sent me a Gardiner DVD with an excellent section on gas welding.

The idea is that these fusion welds are done without filler rod and because there are no different materials introduced they are easier to planish. I’m all for that since planishing MIG welds is a bit of a beating. MIG welds are very hard because of the carbon added in the process.

Here’s my setup and some of my first attempts to weld some test coupons. I think it will be a while before I’m ready to weld a three foot long seam down the middle of a quarter panel. :) Tight fitting panels are essential to success. Keeping a consistent heat affected zone, HAZ, is key to prevent panel warping. It’s tougher than it sounds.

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I’m going to practice on more coupons and then attempt to weld a patch panel on the dogleg of a 59 Chevy pickup. Let’s see how it goes…

Don
 
Nice work Don. Looking pretty good. One thing you will notice when practicing on coupons of that size is that when switching to a real panel you need a bit more heat in the torch. At least that was my experience when learning. Also .035 MIG wire works pretty good when needed. I don't like the 1/16" rod as it cools the puddle too much. Sand the copper coating off the wire if using the MIG wire.
 
You can see the variation in the HAZ in the corners of the coupons where I clamped it to the edge of my 1” thick welding table. Will be interesting to see how it goes on a real panel for sure. Fit up will be a challenge no doubt.

Don
 
metalman said:
RG-45 or RG-60 are fillers for gas welding steel. The RG-45 is softer and more than adequate for auto panels.
Click to expand...
I bought R45. Is that different than RG45? Does the G stand for gas?
www.ebay.com

Westward 41R243 36" Welding Rod 1/16" Dia., Aws R45, 1 Lb. | eBay

Zoro Select B08200.037.0350 Grade 2, 3/8"-16 Hex Head Cap Screw, Black Oxide. Zoro Select B08450.050.0350 Lag Screw, 1/2 In, 3-1/2 In, Steel, Hot Dipped. & Recepticles. Electrical Outlets. Light Industrial.
www.ebay.com

Don
 
dhutton01 said:
I bought R45. Is that different than RG45? Does the G stand for gas?
www.ebay.com

Westward 41R243 36" Welding Rod 1/16" Dia., Aws R45, 1 Lb. | eBay

Zoro Select B08200.037.0350 Grade 2, 3/8"-16 Hex Head Cap Screw, Black Oxide. Zoro Select B08450.050.0350 Lag Screw, 1/2 In, 3-1/2 In, Steel, Hot Dipped. & Recepticles. Electrical Outlets. Light Industrial.
www.ebay.com

Don
Click to expand...
G stands for gas. R=rod, G=gas. 45,000 psi tensile strength. Mig and Mig wire is commonly 70,000 psi, 70S2 or S6 for example.
 
dhutton01 said:
Because I have no conscience I like to murder at least one new skill per year. :D This year I’ve decided to attempt butt welding panels with an oxy acetylene torch. I got a torch setup from Dagger Tools and watched a couple of YouTube’s. Big Dave also sent me a Gardiner DVD with an excellent section on gas welding.

The idea is that these fusion welds are done without filler rod and because there are no different materials introduced they are easier to planish. I’m all for that since planishing MIG welds is a bit of a beating. MIG welds are very hard because of the carbon added in the process.

Here’s my setup and some of my first attempts to weld some test coupons. I think it will be a while before I’m ready to weld a three foot long seam down the middle of a quarter panel. :) Tight fitting panels are essential to success. Keeping a consistent heat affected zone, HAZ, is key to prevent panel warping. It’s tougher than it sounds.

View attachment 27277View attachment 27279

I’m going to practice on more coupons and then attempt to weld a patch panel on the dogleg of a 59 Chevy pickup. Let’s see how it goes…

Don
Click to expand...
These are great for a first attempt! If you can weld it and not warp the crap out of it and keep from blowing a bunch of holes, you’re doing well in my book.
 
70s2 has silicon and titanium, which helps with controlling impurities…..from memory.
I used a lot of 70s2 on 4130 chromoly.
I’m sure Metalman or DAT can elaborate.
It’s been 20 years since I did anything technical.
 
Chris_Hamilton said:
@metalman Ernie, I have only used S2 TIG rod and MIG wire? Is there a difference in what you recommend? If so, what? Softer?
Click to expand...
Yes the gas rods are softer. The Tig and Mig rod or wire is harder. The numbers tell the story, 70S-2 or 6 is 70,000 psi tensile. The 45 or 60 gas rods are 45,000 and 60,000 psi. So RG-45 is almost half as hard as the Tig, Mig wires.
Nothing wrong with using the S2 fillers with gas welding, just that the RG gas rods are specifically designed for ox/acet and you would likely notice a difference when planishing. I don't know the chemical answers. IIR the tensile psi of cold rolled sheet metal is only around 36,000 psi so the RG-45 rod is still stronger.
Don mentioned strictly fusion to not introduce a different alloy or hardness into the welds but the reality is filler rod is needed more often than not.
An alternative to filler rods is to sheer the rods from the cold rolled metal you are using and twist them to straighten. Then the filler is the same as the panel. Not easy without a good sheet metal sheer. I have done that with aluminum for a perfect color match.
I used plenty of 70S-2 with Tig on sheet metal and I have used RG gas rods with Tig.
I use an old Smith Airline torch for gas welding sheet metal. I do it about every 10 years or so just to remind me where it all came from. Then I go immediately back to Tig. Not a fan of Mig welding although it does have it's place.
 
metalman said:
Yes the gas rods are softer. The Tig and Mig rod or wire is harder. The numbers tell the story, 70S-2 or 6 is 70,000 psi tensile. The 45 or 60 gas rods are 45,000 and 60,000 psi. So RG-45 is almost half as hard as the Tig, Mig wires.
Nothing wrong with using the S2 fillers with gas welding, just that the RG gas rods are specifically designed for ox/acet and you would likely notice a difference when planishing. I don't know the chemical answers. IIR the tensile psi of cold rolled sheet metal is only around 36,000 psi so the RG-45 rod is still stronger.
Don mentioned strictly fusion to not introduce a different alloy or hardness into the welds but the reality is filler rod is needed more often than not.
An alternative to filler rods is to sheer the rods from the cold rolled metal you are using and twist them to straighten. Then the filler is the same as the panel. Not easy without a good sheet metal sheer. I have done that with aluminum for a perfect color match.
I used plenty of 70S-2 with Tig on sheet metal and I have used RG gas rods with Tig.
I use an old Smith Airline torch for gas welding sheet metal. I do it about every 10 years or so just to remind me where it all came from. Then I go immediately back to Tig. Not a fan of Mig welding although it does have it's place.
Click to expand...
I typically use welding rods and tap them flatter. Running them through a wheel works nicely I’m sure.
 
No comment on the welds as they look good to me!

BUT I have the same Harbor Freight welding cart and while it is a good value for the money be aware those bicycle wheels will soon fail!
I spent about $60 on a good set of replacement plastic rims that have lasted so far. Other than that I have been pleased with the cart. Other cart prices are many multiples of the HF one.

Another one of those Harbor Freight tools that are about 80% complete when you purchase it and then the end user has to add the last 20% for it to work well.
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I have a small set of oxy/acetylene tanks but find I mainly use them for the cutting torch.

Way, way back when did my first restoration of a 1968 Mustang, it was what I used to weld in patch panels. It was so long ago, I would probably have to relearn the whole process again.

A ways back I bought my gas MIG welder, which at the time I was told would be much better for the work I was doing. It is set up with .023" wire and once dialed in produces some decent welds. So this whole thing seems like a step backwards to me.

I have never had welding training, other than my dad and he used the coat hangers as well. So is there some great advantage to this fusion welding?
 
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