10/09/2026
Day 8 of 30, The Invisible Signals.
You’ve spent an hour filing. There’s still a gap. So you reach for more solder, thinking at least it’ll hold.
Here’s what that blob is actually doing. It’s not holding your join, it’s hiding the one thing that would’ve told you why it didn’t flow properly in the first place.
A flush join gets its strength from full contact, both sides touching all the way along. A gap filled with solder isn’t that, it might hold for now but it’s nowhere near as strong.
I used to do this too. If a join was taking too long to get flush, I’d think “good enough” and bury it in solder.
Use a small pallion instead, about 1mm square. It won’t hide anything, so if it doesn’t flow right you’ll actually see why, and that’s the bit that teaches you something.
Haven’t seen Day 4 yet? That’s where the flush join test lives, go check it before this one.
Ever piled on solder just to move on? What happened? Comment below 👇