Welding 1/4" steel- Mig or stick?

   / Welding 1/4" steel- Mig or stick? #1  

BTackett

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I am going to be attempting to weld 1/8" thick 2in square tubing to flat surface and then welding a 2 1/4" flat bar stock that is 1/4 thick on the ends. Will a Mig welder handle this? Or should I let someone stick weld it? I am taking a cat O plow and making it into a cat I by beefing the arms up.

I have used the Mig on 1/8" small stuff and plenty of sheet metal but nothing this thick.


Any ideas?

thanks,
Bill
 
   / Welding 1/4" steel- Mig or stick? #2  
Without know what MIG you have and the specs on it, it's impossible to answer your question.

My Miller 210 would do it effortlessly...
 
   / Welding 1/4" steel- Mig or stick?
  • Thread Starter
#4  
Ooops, sorry. It is a Craftsman # 20569 model. 120Vac, single phase max 85 amp output with a 40% duty cycle. It states in the manual that it will do from 24gauge to 3/16 in a single pass but thicker metals can be done by beveling. I call them fillet joints but the book calls is beveling??

I used to dream about the Miller 210 but Craftsman $299 sounded better.


thanks,
Bill
 
   / Welding 1/4" steel- Mig or stick?
  • Thread Starter
#5  
I used all my gas on sheet metal welds so I will also be using a .030 flux core wire without gas on these welds.

Bill
 
   / Welding 1/4" steel- Mig or stick? #6  
Mig will do the job, any thicker go stick. I suggest using the thickest wire the machine will handle.
 
   / Welding 1/4" steel- Mig or stick? #7  
It will do it but in my own opinion is more critical to fabricate and fit your joints properly than how hot you make the weld. There are some drawbacks to using flux core wire, one is that it is a more brittle weld than welding with gas. the advantage is that it can penetrate deeper. I put a new bed on my dump truck using my Lincoln sp125 and I havnt had any problems with welds breaking but I did however spend a lot of time on properly fitting the joints. Ive also welded 1/2" plate with it but for metal that thick I pre heated the metal which helped.
 
   / Welding 1/4" steel- Mig or stick? #8  
I could be wrong, but I suspect that this is about the limit for this machine. It's not a lot of welding in linear inches, but it may be enough to trip the thermal overload switch. You might end up welding some and waiting for the machine to cool back down to do the next weld.

I'd tack it together and then do the welds.
 
   / Welding 1/4" steel- Mig or stick? #9  
According to what was said in another post you can bevel the edges of the metal then make a pass and weld that grind it smooth then keep on making passes until you have filled in the bevel. This is a pretty common topic and in the thread I am talking about there were some pretty firm opinions aired. I know my 175 amp mig welder says that it will do 1/2 in one pass. I have been making a new mounting bracket for my forks. I am using 1/2 in x 3 in strap to make the mounting bracket. It is doing well I am getting great penetration and am very happy with the results. On the back plate the forks actually ride on it is 3/4 inch I had to put a piece in the middle to make it wider. I beveled all of my edges and made repeated passes on the 3/4 inch pieces and I am very very happy with the results on them.
 
   / Welding 1/4" steel- Mig or stick? #10  
I've never had much luck with 120ac mig welds on anything over 1/8". If I have to weld anything thicker than that I go 220 mig or stick. I just don't think you get enough penetration with 120volts.
 
 
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