Weld strength and HAZ question

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Here's a couple questions for the experts coming from a hobbyist:Between SMAW, MIG, and TIG, which process produces the strongest weld?  Does the size of the HAZ come into play and affect the answer?  For example, I read on the internet that SMAW must never be used for roll cages because the HAZ is larger than it would be for MIG.  On the other hand I know there are a lot of structural welds done with SMAW. I tried testing MIG vs. SMAW with a little destructive testing in my garage.  I welded up some U-shapes from 1" square mild steel tubing and collapsed them with a large hammer.  The results were inconclusive, but SMAW was looking pretty good.  Operator skill probably skewed the results.  As a side note on the HAZ, both processes seemed to leave the metal glowing yellow around the bead until it cooled.  I could not tell a difference in that regard.  How could MIG have a smaller HAZ while still achieving the same penetration?Comments?Thanks!(p.s. I'm not working on any big safety-critical project, just trying to increase my knowledge.)
Reply:Originally Posted by forestdwellerBetween SMAW, MIG, and TIG, which process produces the strongest weld?
Reply:Originally Posted by KelvinThe same thing 90-year-old poontang smells like:Depends.
Reply:Originally Posted by forestdwellerHere's a couple questions for the experts coming from a hobbyist:Between SMAW, MIG, and TIG, which process produces the strongest weld?  Does the size of the HAZ come into play and affect the answer?  For example, I read on the internet that SMAW must never be used for roll cages because the HAZ is larger than it would be for MIG.  On the other hand I know there are a lot of structural welds done with SMAW. I tried testing MIG vs. SMAW with a little destructive testing in my garage.  I welded up some U-shapes from 1" square mild steel tubing and collapsed them with a large hammer.  The results were inconclusive, but SMAW was looking pretty good.  Operator skill probably skewed the results.  As a side note on the HAZ, both processes seemed to leave the metal glowing yellow around the bead until it cooled.  I could not tell a difference in that regard.  How could MIG have a smaller HAZ while still achieving the same penetration?Comments?Thanks!(p.s. I'm not working on any big safety-critical project, just trying to increase my knowledge.)
Reply:Originally Posted by forestdwellerHere's a couple questions for the experts coming from a hobbyist:Between SMAW, MIG, and TIG, which process produces the strongest weld?  Does the size of the HAZ come into play and affect the answer?  For example, I read on the internet that SMAW must never be used for roll cages because the HAZ is larger than it would be for MIG.  On the other hand I know there are a lot of structural welds done with SMAW. I tried testing MIG vs. SMAW with a little destructive testing in my garage.  I welded up some U-shapes from 1" square mild steel tubing and collapsed them with a large hammer.  The results were inconclusive, but SMAW was looking pretty good.  Operator skill probably skewed the results.  As a side note on the HAZ, both processes seemed to leave the metal glowing yellow around the bead until it cooled.  I could not tell a difference in that regard.  How could MIG have a smaller HAZ while still achieving the same penetration?Comments?Thanks!(p.s. I'm not working on any big safety-critical project, just trying to increase my knowledge.)
Reply:Thanks Snoborder!  Travel speed makes sense for MIG having a smaller HAZ.