I'd say your getting where you want to go? Coming along.
The expression, "a dog chasing its tail". That's what comes to mind? I've been there. So here's how to solve it.
First off, solid to liquid. Your getting to much liquid. You need more solid.
I know...what in God's green earth am I talking about? Too much Liquid?
Ok...take your breakfast cereal, poor it in a bowl and start adding milk. Stop when you add to much?
Now, think of how much more crunch you'll have with less milk. Too much liquid.
Say you added to much milk, no big deal, add more crunch. Or drain away the milk.
Metal eroded thin thru oxidation corrosion is just that, thinner. I'd like to say thinner the flake the quicker it gets soggy. That's only partially true. The reason why is kind of obvious, yet not thought out, it's the amount of milk. Ha!
But hey...welding to the thinner pieces requires some adaptation.
Here's one, stop. That's the hardest to master.
But stopping is the first step.
Added to much milk, quit pouring. Leave it an hour for the flakes to swell and it'll look solid? But yes, stopping.
Second. Remember building a house doesn't start with the first two by four it starts with a plan. If you know the area is weak you have to plan for it. Point to the good piece, let it take the heat and as the deoxidizes in the wire from you filler meet thinner rusty spot to be welded, you watch the plastic flow of metal tag it together. If it doesn't rule number one.
Let the metal roll. Like lava, it will flow. Take advantage of it. If it get to hot, too liquid, no longer mush but wet, running and falling, stop. Rule number one.
Build on the good, getting it to flow. Again, dog chasing a tail, yes. Remember, metal is metal, some just thicker, some harder. And they make grinders for a reason.
You sculpt it. Grind flush/flat or leave it thick and round? Small amounts are easier then big ones but? I'm just saying, put it on grind it thin, put it on grind it thin. No harm no foul, it metal. You will rebuild the surface.
You could also ask yourself, self...should I have replaced a bigger piece? That's the time when you go and lift the bowl, it slips thru your fingers and hit the counter, milk and flakes everywhere? Yup?
But hey...I grind stuff so I try and keep to a minimum weld size. Pulling a longer stick out narrows the arc width, the longer wire doesn't heat as much, thickening the weld pool. It builds better on it self.
Adding more wire feed speed does something different. Think of it this way, your falling from a 10' ladder, now fall faster.
Third...to much liquid. Not all my weld are pretty. What for? I'm going to grind them anyways? As far as it goes, when it comes down to it, I weld hotter, faster and more then I should. I'm sticking two pieces together not practicing to pass a test. If you can't thicken things up thru process controls and variables...stop. Rule number one.
Now I'm rambling on, because I'd be again not coming clean if I didn't mention wire size? That under rated moot point of minor interest is that flake. So ask your self...self, what get soggy quicker, one big flake or one little one? Depending on a number of things, factors...reaction time being one? Easier to melt less off of something large then control the amount you melt from something small? That make sense?
The money shot.
I mentioned draining the milk away. Chill strips. Suck away the heat, provided backing to shape the bead that falls thru. Take the liquid to a solid quicker.
You've heard the expression about getting it together? Solid, mush, liquid. Easier to pack and shape a solid or a mush then the liquid.
My rule number four. It's ok to do things twice. That's the wonderful thing about metal. Cut it out and do it again. Or, weld it in and replace a another smaller piece?
I do hope my reply finds itself as a benefit to someone?
Hard to say? Hard to tell? But deep just the same maybe?