Shave a Hair Off a Cut
Registering a workpiece against a stopped miter saw blade so the cut removes a few thousandths instead of a full kerf — the way to close a joint that's barely long.
Caulk Is for Corners, Filler Is for Flat Seams
The rule that separates clean trim from cracked paint lines: caulk belongs at change-of-plane joints (where trim meets wall), and two-part wood filler belongs at same-plane joints (seams and scarfs in the trim itself). Caulk in a flat seam shrinks and telegraphs.
when to use caulk vs wood filler, fill gaps in trim, caulk line keeps cracking
The Problem
Caulk is the universal answer on too many jobs — including seams in the face of trim work, where it's the wrong material. Caulk stays flexible and shrinks as it cures; in a flat butt seam or scarf joint it dips, collects paint differently than the wood, and reappears as a visible line within a season.
The Main Rule
Change of plane → caulk. Same plane → filler.
- Where two surfaces meet at an angle — baseboard to wall, casing to drywall, crown to ceiling — the joint moves seasonally and needs flexibility. That's caulk's job.
- Where two pieces meet in the same flat plane — butt seams in a long baseboard run, scarf joints, miter faces — the joint needs a rigid, sandable fill that disappears under paint. That's a two-part wood filler (the Bondo-style catalyzed fillers; several brands make one). Fill the seam, let it kick, sand it flush, and the joint is gone for good.
Pro tip: Two-part filler cures by chemical reaction, not evaporation — which is exactly why it doesn't shrink back into the seam the way caulk and one-part spackle do. The mixing step is the price of a joint that stays invisible.
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