Welding mufflers

[cookies]

The wire feed speed is your amperage adjustment on that style mig making it a pta to get dialed in to make decent welds. Essentially your having to fight the machine to use it, you can change wire diameter to help offset the required feed speed. I think there are a few videos out there showing how to modify that model of welder with a bigger capacitor for a more useable unit. I would suggest looking for a used infinite adjustable unit if you plan to weld thinner materials or even make solid welds. One thing never mentioned is you need to have a 30 amp dedicated circuit to run those 110 welders or you will risk damaging them from under current.

 

[unknwn]

Something I learned while using my TIG for repair work is that the triple de-oxidised filler wire I used for nearly all the shielded-gas repair work also worked wonderfully for oxy-acetylene work too'.
That 3-deox flows like butter under flame.
If you can get your muffler/exhaust repairs made solid using the steel filler, then follow up with a low-heat bronze for brazing as a filler for any porosity and smoothing out for appearance left to be done in the repair.
The problem with -just- brazing for this sort of work is that often-time just brazing can be vulnerable to cracks & associated failure.

 

[gumneck]

Heinmannm has you the info you need. Get yourself a Mig setup with the correct Argon/CO2 gas 75/25 and you'll throw away your present welder if it does not support Mig.

 

[Canyon Angler]

The problem with -just- brazing for this sort of work is that often-time just brazing can be vulnerable to cracks & associated failure.

Not in my experience. If anything, I've found brazed joints to be more ductile than those welded with steel, particularly migged joints subject to quenching by the substrate. Those joints can get harder than the hammers of hell, one reason why tig is preferable for auto body work where you want to sand/blend the joint fair. YMMV...

 

[ning]

If your flux core wire is E71T-GS, realize there are no standards for that stuff and quality varies wildly.

Make sure you're using E71T-11. Don't run out the old stuff, just throw it away, unless you've got a friend learning to weld that this like to turn into an enemy.

Also, my experience with the really thin metals and wire is you definitely don't want to run the wire fast as that'll burn it through quickly. Try to find some similar scrap and practice different heat & speed; on my little wire feeder (Miller 130) I think I'd be on #1 with ~15-20 max speed.

 

[ssteve58]

Practice on something else. You have done a great job fabricating the parts. Treat the welder like a spot welder. High heat, spot, let off on the trigger, move a little, repeat. Practice on something else similar first.

 

[davidwyby]

Practice on something else. You have done a great job fabricating the parts. Treat the welder like a spot welder. High heat, spot, let off on the trigger, move a little, repeat. Practice on something else similar first.

Exactly. Small wire. Go MiG.

 

[calamari]

The better the welding machine, the better the weld. The better the brand of flux core, ditto. I'd say you have a lot more "weld" material on that piece than what you need to hold it. With a smaller bead it would look better but as someone noted, it doesn't look like it's going anywhere. Looks nice from the other side.
Practice on something with similar material, thickness and joint mechanics. I was going to use my small 220v Lincoln MIG welder to weld aluminum so I practiced on scrap aluminum long enough to understand what the machine would do and got reasonable beads. I also got quite a substantial aluminum sculpture of scrap pieces that "SHE" refuses to let me put on the mantle for our friends to appreciate.

 

[Huskybill]

I do a lot of welding (mainly stick and tig) but I've found it easiest to braze mufflers, using brazing rod and oxy-acetylene. I know that doesn't help you with your mig rig, but it might be an excuse to get a O/A rig. They're handy as hell for heating, brazing, cutting, etc...you'll get plenty of use out of it!

I don't have a lot of hood time on mig, but in general, if you're welding pieces with different thicknesses, you want to start your puddle on the thicker piece, then "wash" it over to the thinner piece. And if doing a lap joint, start your puddle on the lower piece, then wash it over to the top piece. (If you start on the top piece in a lap weld, you'll just melt back the edge without fusing it to the lower piece.) HTH...

I plan on trying a low temp silver soder with oxy/acc

 

[Huskybill]

With MIG welding you may need stargon gas. Using gas will establish the arc better when you start over flux core wire. I would put tac welds around the circle then collect the dots with a continous bead. The the exhaust pipe won’t warp if you weld it with no tac welds.

 

[TheTone]

Helps to have the steel thickness as close to the same as you can get too

Yes. MIG welding a thick piece to thin piece will usually burn through the thin piece and fail to penetrate the thick piece. I have a Lincoln 110v and weld mufflers at power setting A with a wire speed at 3. With metal this thin, spot weld the piece at 4 points and then alternate spot welds all around until they join. It's just too thin to do a nice continuous weld. For contrast, repairing a 1/2" fireplace grate would be D with a 7 wire speed on my welder.

 

[Jasonrkba]

While the welding job does not look good it does hold well and you can't see it on my 10-10S. This saw was damaged by the previous owner.

 

[pioneerguy600]

Looks very nice, reminds me of my Pioneer 1450 muffler, some of the bigger P series also.

 

[Jasonrkba]

I forgot to mention I removed the baffle and installed a stainless steel mesh to act as a spark arrestor. I ran it today to retune it. Wow it screams and a little more responsive.

 

[mutt07]

Im teaching myself how to weld. I have a harbor freight mig welder chepo. I am trying to weld a small piece of pipe to a cover I made for a 10-10. The welder has two heat settings min and max. I had the heat on max and the wire at 3.5. I just dont seem to be getting enough penetration. I know my weld looks bad as I said learning. Any ideas what Im doing wrong?

Hi Jason. Keep this in mind. Preheat steel items when using smaller or weaker welding machines. Also if you are using GMAW, which is gas metal arc welding then you have to contain the inert gas which acts as a flux. If you are using fluxed core wire you do NOT use inert gas. Make sure your electrodes are set properly for what you are welding. Should be on inside lid of machine. If all checks out get an acetylene torch and move it over the items to be welded until dull red and preheated. Then try to weld up. Also try to PULSE the trigger one pull off two pull off three pull.... muffler material is thin and cheap junk. Might help you. Let me know.

 

[LoneOak]

No filler tig welds.

 

[Jasonrkba]

Im going to play around more in the morning. I have an idea for dual exhaust using smaller pipe. Think staggered short pipe.

 

[Jasonrkba]

The paint is still wet but build #2.

Preheating the metal made a huge difference.

 

[mutt07]

The paint is still wet but build #2.

Preheating the metal made a huge difference.

Yea. Ole timer when I was a kid told me when he saw us struggling with trying weld up a mini bike frame. My buddies dad had a old wire welder but like for bodywork panels. This old timer said He could weld anything with any machine as long as it’s preheated. He said that little box can weld a building together long as it’s preheated. So in my head that stuck. Lol. Preheat!! Over the years that’s what I’ve done. They wouldn’t let me preheat for the 6 G test tho haha
Go figure. God bless btw. Looks great

Mark