My new HF welder

[Chris64]

So I decided to try and repair some of the rust on my hood. It's probably not worth repairing given the price of a new hood and the level of corrosion that goes through the front (top skin and bottom)...but before I try to tackle the cab, I see this as a good learning chance. I used a sand-blaster adapter on my pressure washer to clean off the rust and that worked really well except for all the sand that got in my hair.

Welding did not go well. I was ready to throw in the towel. I have a Lincoln Pro-175 Tig that I've used quite a bit before but never anything as thin as body sheet metal. Not to mention rusted out super thin swiss-cheese metal. My plan was to put in patches (new 12ga 18ga sheet metal) on the big areas and maybe just fill the small pin holes. It all just translated to burning holes. After turning the amps WAY down it got better but it was still acting like it didn't want to arc and by the time it did it just burned through before I could move in with filler. I could get about 2/3 welds to work but that 1/3 was burning a hole through. I've watched plenty of videos of people tacking in their "patches" and even the skilled guys who tig will use their mig for this. That got me wondering if this is the wrong tool for the job.

Also my argon was almost empty. Thinking of what that will cost to refill my argon and my utter failure to do clean welds with a tig, I bought the $150 HF Titanium 125 mig welder.

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I have to say, so far I'm impressed. It's 120v first of all so that makes it way more mobile. It only weighs about 15 pounds. The settings needed to be turned WAY down still but I could easily do little peck mig welds that had good penetration and is WAY easier to not burn through than my tig (for my skillset anyway). And if you do, it was relatively easy to fill with a bunch of little welds. Also a lot less heat.

I still need to do more dialing in and the spatter sucks, but for body panels I think this will work great. I'm planning on tacking in a ~1" wide backer plate just because it seems safer (less likely to burn through).

I can't wait to get back to work on it. OK, let me have it

 

[Fri00]

Use copper backers when welding over thin areas with mig, it’ll help prevent burn through.

 

[squaredeal91]

Copper works really good for that. The first time I learned about that trick It blew my mind lol

 

[Sad Sack]

Great source of information:

MIG Welding Tips and Techniques for Beginners | MillerWelds

Metalworker Ron Covell shares his best MIG welding tips for beginners, including how to set up your machine and techniques.

www.millerwelds.com

 

[Latvius]

The rusty metal will just burn until you get to good metal. It's not the amperage or the welder you are using. It's just one of those things where you have to judge is it easier/quicker to try and weld pin holes or cut it out and weld in a patch.

 

[YakkoWarner]

TIG welding is hard - I havn't been able to get the hang of it yet. It also doesn't work if there is any wind or air movement. But what the previous post says about rusty metal is 100% correct - if its corroded that thin it will just burn away. It took me days to get all the pin-holes in the small (12x6) area under the pedals on a British car because they often became screw-size or pencil size holes. Fortunately that wasn't a structural area and cutting out/replacing would have been very hard because of where it was. On the passenger side I did do a cut and patch because there was more room to work. I have not had the opportunity to try a copper backing piece - mainly because I don't know where to get one locally.

 

[legopnuematic]

TIG welding is hard - I havn't been able to get the hang of it yet. It also doesn't work if there is any wind or air movement. But what the previous post says about rusty metal is 100% correct - if its corroded that thin it will just burn away. It took me days to get all the pin-holes in the small (12x6) area under the pedals on a British car because they often became screw-size or pencil size holes. Fortunately that wasn't a structural area and cutting out/replacing would have been very hard because of where it was. On the passenger side I did do a cut and patch because there was more room to work. I have not had the opportunity to try a copper backing piece - mainly because I don't know where to get one locally.

Harbor freight used to sell copper welding spoons.

Or take a piece of copper pipe and smash it flat.

 

[legopnuematic]

12 gauge for patches? That’s like .100 thick. The OE metal should be 18-19 gauge (could be thinner or thicker depending on the stamping, if an area is a stretch or shrink, deep draw, etc).

What can help on a troublesome area is I focus the torch over the filler metal to heat and flow it onto the parent metal. The wrong thing to do for structural work, but body panels is a different game.

Also more amps is generally better than lower amps. Too low of amps will just heat soak the material and not form a useful puddle. Get in and get out. I also use 1/16” filler rod for almost everything. Just my preference though.

 

[Chris64]

12 gauge for patches? That’s like .100 thick. The OE metal should be 18-19 gauge (could be thinner or thicker depending on the stamping, if an area is a stretch or shrink, deep draw, etc).

What can help on a troublesome area is I focus the torch over the filler metal to heat and flow it onto the parent metal. The wrong thing to do for structural work, but body panels is a different game.

Also more amps is generally better than lower amps. Too low of amps will just heat soak the material and not form a useful puddle. Get in and get out. I also use 1/16” filler rod for almost everything. Just my preference though.

You're right - I think it's 18ga. It's the same as the stock sheet metal.

Also, you're right about heating the filler. That's what I found worked-ish. It was still super unreliable but it was the only way I could keep it from burning through.

 

[Bennyt]

Just in case you need supplies. Never expires. Been using it for around 7 years at HF.

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[Hilllbilly]

Harbor frate welders .... I hear they're better than Miller ....

 

[Steelbuddha]

Re: the copper welding spoon, there's also this hands-free gizmo:

https://www.amazon.com/dp/B07ZG59SHV/

 

[squaredeal91]

Re: the copper welding spoon, there's also this hands-free gizmo:

https://www.amazon.com/dp/B07ZG59SHV/

That's pretty slick

 

[Bextreme04]

Harbor freight also has their 10 days of deals going on again right now. Tomorrow is $300 of the Titanium unlimited 200 multiprocess welder and 30% off all welding cabinets and carts.

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[Ricko1966]

TIG welding is hard - I havn't been able to get the hang of it yet. It also doesn't work if there is any wind or air movement. But what the previous post says about rusty metal is 100% correct - if its corroded that thin it will just burn away. It took me days to get all the pin-holes in the small (12x6) area under the pedals on a British car because they often became screw-size or pencil size holes. Fortunately that wasn't a structural area and cutting out/replacing would have been very hard because of where it was. On the passenger side I did do a cut and patch because there was more room to work. I have not had the opportunity to try a copper backing piece - mainly because I don't know where to get one locally.

You make one get apiece of copper tubing from your scrap pile,beat it flat with a little curve with a hammer or vice.
Just noticed that's flux core. I think you'd be better off with a gas shielded mig and 75/25 mix for body work.