Hi,
Yet another newbie here; not just to this site, but to MIG welding as well.

For those who are pretty experienced, I suppose welding a solid 1/2" round bar
through a 16 gauge tube at a right angle is no big deal. For me, and doubtless many others, its a pain to weld hot enough to cut into the round bar without blowing holes in the light gauge tubing.

I haven't tried this, but I'm wondering...What if you were to put say an inch or so of #8 or 9 steel shot on the inside of the tubing so it packed around the 1/2 inch bar prior to welding? Wouldn't this work to effectively increase the mass of the thin tubing?

I remember in my early stick welding days chasing a pinhole in a Harley gas tank for about six inches before I gave up and bought my buddy a new tank!

No pro here!