Welding my floor

Mig welding a patch into my drivers side floor - where's the best place to ground the welder?

Battery is off, red rag underneath will be soaked with water and I have a fire extinguisher at the ready. Anything else I should do?

 

Get it as clean as you can where you're welding.


What size wire you have in the welder?


Do you have something thin to practice on?

 

Oh yeah, planning to hit the edges with the flap disk.

0.030 wire

I'll practice on the offcut of the 16ga I cut the patch from, thanks for the reminder - this is why it's good to take a step back before burning steel!

 

Yeah you might consider smaller wire, depending on how practice goes. I did some welding on my bed a while back. The results were, uh, suboptimal.

 

Oh man, while I appreciate the quick reply and solid advice, I just can't bring myself to "like" that last post. Way to give a guy some confidence lol

0.030 is all I have. Worst case I tack it in and take it round a buddy's house to finish it off I guess.

 

No shame in just doing a zillion little tack welds. Maybe pull up some youtube videos on it, there are techniques to keep it from warping.

 

Flux core or solid wire with gas? You’ll get a cleaner weld and go can with a slower feed if you are doing gas vs flux core. Definitely practice...I’m gonna weld a hole in my bed soon and plan on practicing on quite a bit of scrap.

Also, .030 is pretty damn thin. I think my 110V welder is set up to run .030 and .035

 

Flux core. I guess that's not technically mig

 

Hey man no shame. Most MIGs come with a spool of flux core to start...I just burned through mine. It’s great for getting broken bolts and stuff out, dirt cheap and don’t have to worry about gas. Simply point and shoot.

I’m definitely not a welding expert but I think you’ll have better luck with gas. I wanna sayyyy CO2 or an argon CO2 mix but don’t quote me on that. Your welder should have a little “idiot chart” somewhere on it that gives you gas, wire, voltage, and feed rate recommendations for the metal you’re welding.

 

I plan to get a C75 bottle at some point but yeah, time and money. Good point about the idiot chart - just checked and it gave me the same settings as practice resulted in. Speaking of which..


Not super confident here lol.

 

The tack on the left looks okay..what’s the underside look like? Did you get good penetration?

 

https://youtu.be/C0M5tUQSaps

Watch this video, I love ChrisFix. He gives a bunch of good tips too

 

They can`t make self shielded wire yet smaller then .030 "

prep work is 95 % welding is the other 5%

You can cheat by using a Aluminum heat sink if things are to hot under the joint.

Lap joints are much easier in thin material then butt joints.

Practice practice good idea to have a Fire Watcher that pays attention rather then once the fire is involved

Pay attention to wiring harnesses fuel or brake lines under the floor .

Did I say practice !!

 

I just decided this is my practice piece since it will be hidden under the carpet

 

So my welder has 4 settings - min/max and 1/2, then wire speed 1-10. Tack on the left was min-1, speed 3. Cheat sheet says for 16ga use min-2 and that is the middle tack. Min-1 did not get good penetration but min-2 was blowing holes. I decided to use min-2 and pull back a little but it was still blowing holes so I dropped back to min-1 and turned the speed up a little. Still blew some holes, I maybe should have made the patch bigger to find better steel but all in all not bad for a first try. I'm going to go drink a beer and decide whether to take it to my buddy to finish or just epoxy over it. Leaning towards the epoxy.


Quench bottle for small fires

As done as it will get from me.

 

Oh and by the way - if you live somewhere they salt the roads and you don't have weathertech or similar mats, go buy some right now - that is straight salt you see piled up against and on top of the air duct:

 

Looks pretty dang good for flux core...make sure to put undercoat or some sort of good paint over it and check for any holes with a flashlight.

 

This is true of just about everything. If you prep right, the job will come out fine.