Putty

Putty is a moldable repair and sealing compound used to fill holes, seal joints, and rebuild damaged areas in wood, glass, metal, and more. Depending on the formula, it may harden solid, stay slightly flexible, or remain non-hardening. Homeowners use putty to repair trim, set window glass, seal sink drains, patch small defects, and prep surfaces for a smooth paint finish.

What Is Putty Made Of?

“Putty” is a broad term for paste-like materials that cure or set after application. Common chemistries include:

• Traditional glazing putty: finel y ground chalk (whiting) mixed with linseed oil.
• Painter’s/wood putty: oil- or latex-based binders with fillers and pigments.
• Epoxy putty: two-part resin and hardener that you knead together to start the cure.
• Plumber’s putty: non-hardening oil- or synthetic-based compound for watertight seals.

Each behaves differently. Some harden and can be sanded and drilled; others stay pliable for sealing.

Common DIY Uses

• Filling nail holes and minor dents in interior trim before painting.
• Rebuilding chipped wood corners on sills, casings, and furniture.
• Setting and sealing window glass in wood sashes (glazing).
• Sealing around sink drains, strainers, and some faucet bases (plumber’s putty).
• Quick repairs on metal, wood, or masonry with kneadable epoxy sticks.

Types of Putty and Where They Fit

Glazing Putty (Window Putty)

• Purpose: Seats and seals glass panes in window sashes and creates a smooth, angled bevel.
• Traits: Stays workable long enough to tool; skins over, then slowly cures. Must be painted to protect from weather.
• Use notes: Drive glazing points to hold the glass, apply putty, tool a clean bevel, allow a skin to develop, then prime and paint. Traditional linseed-oil formulas often need 7–14 days before painting; some modern glazing compounds accept paint sooner. Follow the label.

Painter’s Putty (Trim Putty)

• Purpose: Fills small nail holes and surface imperfections in painted wood trim.
• Traits: Usually remains slightly flexible and comes pre-tinted to common trim colors or off-white; sands and wipes clean easily; paintable.
• Use notes: Press in with a putty knife or finger, wipe excess with a clean cloth, let it set, then prime and paint.

Wood Putty vs. Wood Filler

• Wood putty is typically used on finished wood and often comes in colors to match stains. It may remain flexible and is not always stainable.
• Wood filler (not always labeled as putty) is used on bare wood, cures hard, and can be sanded, drilled, and often stained. If you plan to stain, choose a stainable wood filler rather than a colored putty.

Epoxy Putty (Kneadable Sticks)

• Purpose: Structural repairs and gap-filling where a strong, hard cure is needed.
• Traits: Two-part; you knead to activate. Sets in 5–60 minutes depending on product. Bonds to wood, metal, masonry, many plastics. Can be carved, sanded, drilled, and painted once cured.
• Use notes: Great for rebuilding rotted wood after removing soft fibers, repairing stripped screw holes, or patching metal pinholes. Some versions cure underwater—check the label.

Plumber’s Putty

• Purpose: Forms watertight seals under sink flanges, drain assemblies, and some faucet bases.
• Traits: Non-hardening, stays pliable, not for pressurized connections or for use as a pipe thread sealant.
• Use notes: Roll into a rope, wrap under the flange, tighten the assembly to squeeze out excess, then trim the squeeze-out. Avoid on porous stone countertops (use a non-staining plumber’s putty or silicone) and on plastics if the label warns of incompatibility.

How to Choose the Right Putty

• Match the job:
  • Window glazing: glazing putty.
  • Painted trim touch-ups: painter’s putty.
  • Bare wood repairs you’ll sand and maybe stain: wood filler or epoxy putty.
  • Wet-area flange seals: plumber’s putty (or silicone where required).
• Consider flexibility vs. hardness: Exterior joints and moving parts benefit from flexible products; structural rebuilds need hard-curing options.
• Check paint/stain compatibility: Many putties accept paint but not stain. Choose a stainable filler for stained woodwork.
• Indoors vs. outdoors: Some putties are for interior use only; glazing and epoxy options are common outdoors. Always paint glazing putty for weather protection.
• Cure time: If you’re on a tight schedule, look for fast-setting epoxy or quick-paint glazing compounds.

Application Tips

• Prep the surface: Remove loose paint, old putty, dirt, oils, and any rotten wood. Sand or abrade shiny surfaces for better grip.
• Dry fit first: For glazing, ensure the glass sits cleanly in the rabbet and use glazing points to secure the pane before puttying.
• Work small: Apply in thin layers rather than one big blob. It tools cleaner and cures more predictably.
• Tool with a putty knife: Use a clean, flexible knife. For glazing, hold the knife at a consistent angle to create a neat bevel.
• Smooth edges: Feather the edges to the surrounding surface to reduce sanding later.
• Respect cure times: Don’t sand, paint, or stress the repair until the product has set.
• Prime where needed: Many putties accept primer and paint better than bare topcoat alone. Traditional glazing often gets an oil-based primer before finish paint.

Maintenance and Storage

• Keep the lid tight: Air exposure dries out many putties. Store in a sealed container or plastic wrap.
• Condition if allowed: Some painter’s putties can be softened by kneading with a drop of linseed oil or mineral spirits—check the label first.
• Protect glazing with paint: Exterior glazing putty should be painted and periodically inspected; touch up paint to prevent weathering and cracking.

Common Mistakes to Avoid

• Using plumber’s putty on stone or where staining is a risk. Choose a non-staining version or silicone for marble and granite.
• Trying to stain colored wood putty. Use a stainable wood filler on bare wood if the area will be stained.
• Painting glazing too soon or not at all. Let it skin as directed and paint to protect from the elements.
• Overfilling large voids in one pass. Build in layers or use a backer material for deep holes.
• Skipping surface prep. Dirt, oil, and loose fibers lead to poor adhesion and future failures.
• Substituting putty for caulk in moving joints. Use a flexible caulk or sealant where movement is expected.

Related Terms

• Caulk and sealant: Flexible materials for gaps that move; silicone, polyurethane, and acrylic are common.
• Spackling compound: Lightweight wall patch for drywall; sands easily but not meant for structural repair.
• Wood filler: Hard-curing product for bare wood; often stainable and sandable.
• Glazing points: Small metal tacks that hold glass in a sash under glazing putty.
• Putty knife: Flexible scraping and spreading tool designed for applying putty and fillers.

Practical Examples

• Filling trim nail holes: After installing baseboards, press painter’s putty into each nail hole with your finger, scrape flush with a putty knife, wipe the residue with a clean cloth, let it set, then prime and paint.
• Repairing a rounded window sill corner: Remove loose fibers, consolidate if needed, then knead epoxy putty and pack it onto the corner. Shape it with a moistened putty knife, allow it to cure, sand to profile, and paint.
• Re-glazing a pane: Scrape out failed putty, remove broken glass carefully, prime bare wood, set the new pane with glazing points, bed glazing putty and tool an even bevel, let it skin, then prime and paint slightly onto the glass for a weather seal.
• Sealing a sink drain: Roll plumber’s putty into a rope, place it under the drain flange, tighten the assembly until putty squeezes out, trim the excess, and check for leaks. Use silicone instead if the countertop is porous stone.

By matching the putty type to the task, prepping well, and allowing proper cure, you’ll get smooth, durable repairs that blend in and hold up.