The wooden transition doorway bar between the kitchen tile and the living room hardwood completely warped over the winter, bowing up in the middle and creating a massive ridge right where you walk. Everyone in the house has tripped over the stupid thing at least twice this month, and the edge was starting to splinter off into the carpet fibers. I picked up a basic T molding transition track at the store, thinking it would be a simple case of cutting it to length and screwing it down. What a total mess.
The ancient metal channel glued into the concrete subfloor underneath was completely packed with years of compressed dirt and old adhesive crust. Trying to pry the rusted track loose with a flathead screwdriver just ended up chipping the edges of the surrounding ceramic floor tiles, which completely ruined my mood right away. I had to sit there on the floor with a hammer and a cold chisel, aggressively hacking away the hardened mortar chunks millimeter by millimeter just to get a flat surface for the new metal base rail.
Then came the real headache of drilling fresh mounting holes into the solid concrete slab beneath the doorway. My standard drill bit was barely making a dent and just spinning in place, creating a giant cloud of grey dust that got all over the clean kitchen counters. I had to run out to the garage to find a carbide masonry bit and a heavy hammer drill, and my hands were vibrating so bad from the impact that I could barely keep the alignment straight along the layout line.
The new metal track is finally anchored solid into the concrete now and the stained wood top piece snaps directly into the groove with a rubber mallet. The strip sits completely flat against both floor surfaces without any rocking or gaps, and the transition is smooth enough that the tripping hazard is completely gone. The doorway floor boundary is fully fixed.