mig welding

[ANS Performance]

I have a question regarding spot welding , I been triing to make my welds look like tig welds. I been doing this by spot welding continues beeds. takes a little more time , but achieves a tig look. my question is , by welding this way doe's this make my welds weaker, over a continues beed?????

[Dmaxer]

In a word, YES, they're weaker. When you stop and start the MIG weld, you also start and stop penetration and MIG is notorious for lack of penetration on starts anyway. However, the use of these welds does not appear to be any more demanding than stitch welding would handle. Doubtful they'll fail, but if they come apart at the corners, you'll see it quickly.

[Broccoli1]

Weaker.

Ya have a whole bunch of Cold welds now.


Only time to do that with Mig is on thin sheet metal to help control burn through and Distortion-

looks like a front bumper in yer Pic? 3/16"- 1/4"?

[Bodybagger]

Weaker again.

Notice the little craters. They tend to seed cracks. And if the only reason is to make it look like a TIG weld, well, I hate to burst your bubble but it doesn't exactly look like a TIG weld either.

[ANS Performance]

weaker is what i was thinking. the metal is 3/16, the welder set at 1/4 and gas set at .2 thinking that the extra heat for penatration, sheilding gas staying on after, between welds. I purchase the miller 252 a little over a year , so I'm still learning alot. thanks for you help, I'll stick with the steady beads

[Machinist]

It's a weaker weld for sure if you cut it apart you may have voids where you start and stop..

[Sonora Iron]

I recently witnessed this same technique on a project built with 10 or 12-GA. Later the entire project was DP’ed, it looked like a scene from the movie texas chainsaw massacre!

[diamondback]

Little spot welds like those are typically much colder to deposit than a regular weld. That is why it is used on very thin materials. Also as mentioned and eluded to by others there are in fact cracks in each or the craters.

To achieve a "stacked" look with wire feeding in a robotic application and does about the same hand held is to "weave on seam" or whip. Where your arc is traveling ahead of the puddle and then back into it. Much like running 6010 stick. As with any technique there are positives and negatives to whipping. There are other threads out here where we have discussed the differences in penetration, travel speed and ease of application for most techniques so I won't lengthen this out any more than needed. If you'd like further discussion on it just send me a private message and I would be happy to discuss it.

[monte55]

Not to mention the welder cycling so often.