Anything water-based. Said twice on purpose: latex wall paint, waterborne acrylic enamel, water-based poly — all wrong for these fibers. That is the 81303's job.
Large flat fields. The widest brush here is 2"; rolling or a 4" flat covers walls and big exterior fields far faster. Sets are for the cut-and-detail work around the roller, not for replacing it.
Fine artist-scale touch-up. Below roughly a half-inch of line, the 1" is too broad; that is the artist-brush drawer (the line's 80011–80017).
Aggressive scrubbing or cleaning. These are applicators. Nothing in this set is a scratch or strip brush; that is the wire/stripping side of the catalog entirely.
dip a third of the bristle length, tap (don't wipe) the excess against the inside of the can — wiping on the rim starves the brush and loads the heel. Laying off: apply with pressure, level with almost none; the final strokes are long, light, and all in one direction so the flagged tips leave a self-closing texture. Cutting: light load, high grip, let the long corner do the aiming; reload before the bead thins, not after it skips. Cleaning — the part that decides whether this is a one-season or a ten-year set: because these are oil brushes, they clean in mineral spirits / paint thinner, not water. Work the solvent up into the heel (where paint dries first and ruins a brush), flush until it runs clear, then wash with soap and warm water only at the very end to cut the last of the solvent, spin or shake dry, comb the bristle straight, and hang or wrap it so it dries in its original shape. A natural-bristle brush is destroyed at the heel by dried paint and by being stood on its tips — a comb and a wrap after every session is the entire maintenance secret. (See the line's care tools — the 45950 comb, the 43470 spinner — for the ten-year-brush standard.)
Asked at the counter
BUYER QUESTIONS ANSWERED BEFORE THE CART, NOT AFTER THE RETURN
Can I use this set with latex or water-based paint?
No — natural bristle swells and goes limp in water. This is the oil/alkyd/varnish/stain set; the 81303 is its water-safe twin.
What's the difference between this and the 81303?
Only the bristle: black natural here, polyester there. Same three sizes and shapes.
What is the angular brush for?
Cutting lines — trim-to-wall edges, sash, frame-to-glass — using the long diagonal corner. It is what makes the kit a cut-and-fill method.
Why black bristle instead of white?
Black is the stiffer natural grade, favored for oil stains and heavier oil coatings where a bit more backbone helps.
Will one 2" brush paint my walls?
For cutting in and small work, yes; for the broad field, roll it or step up to a 4" flat — a three-brush set is the trim-and-detail kit, not a wall kit.
How do I make it last?
Clean in solvent up into the heel, finish with soap and water, comb straight, hang to dry in shape — never let paint dry in the heel and never stand it on its tips.
