Wood filler and wood putty are both products used to fill holes, cracks, and imperfections in wood. Though they share some similarities and can both be used for minor wood repairs, there are important differences between wood filler and wood putty in terms of their composition, best uses, durability, drying time, sandability, and more. Understanding the distinctions between these two products will ensure you choose the right one for your specific wood repair project.
Composition
The primary difference between wood filler and wood putty lies in their composition.
Wood filler consists mainly of inert solids like wood dust or sawdust combined with binder material like varnish, lacquer, epoxy resin, or polyurethane. Some wood fillers may contain additional ingredients like silica or talc. Wood filler dries hard through evaporation and cures fully over time.
Wood putty contains filler material suspended in a liquid drying oil, usually linseed oil. Some formulas use other oils like tung oil or phenolic oils. As the oil in the putty cures, it hardens the putty. The oil allows wood putty to remain somewhat flexible over time.
Best Uses
Due to their different compositions, wood filler and wood putty each work best for certain applications.
Wood filler works well for:
- Filling cracks, gouges, and holes in wood
- Repairing defects in finished wood
- Patching damaged wood trim, molding, cabinets, furnishings, etc.
- Filling nail holes from removed nails
- Preparing wood surfaces for painting or staining
The hardness and rigidity of cured wood filler makes it suitable for general repairs that need strength and stability.
Wood putty excels at:
- Filling small imperfections in unfinished, raw wood
- Patching nail holes that will be stained or clear-coated
- Repairing defects in woodwork that will remain natural and unpainted
- Smoothing scratches, dents, and scrapes in stained or varnished wood
The flexibility of wood putty prevents cracking or chipping out of the filled area when the wood expands and contracts. It blends into natural, porous wood better than rigid wood filler.
Durability
The structural properties of each material also impact their durability:
- Wood filler forms a hard, inflexible bond as it fully cures. This makes it very resistant to damage after drying. Areas patched with wood filler become as durable as the surrounding wood.
- Wood putty remains somewhat flexible after drying due to its oil-based formula. Though it hardens, it does not bond as rigidly within the wood. Putty may loosen, soften, or fall out over time as the wood’s natural movement weakens the bond.
For repairs that need to endure daily wear and tear, wood filler provides greater lasting durability than soft, flexible wood putty.
Drying Time
Another key difference between wood filler and wood putty is their drying time:
- Wood filler usually dries within 30-60 minutes once applied. Full curing takes 24-48 hours. Quick-drying types may set in about 15 minutes.
- Wood putty takes much longer to dry and cure, often requiring 24 hours or more for the oil to fully harden within the putty. Drying also depends on environmental factors and the type of oil used.
Wood putty’s extended curing time allows more time to work and smooth the putty. But wood filler offers faster repairs when time is limited.
Sandability
The ability to sand wood filler and wood putty smooth after they dry also varies:
- Wood filler generally sands very smoothly with fine grit abrasives. The hardness of cured wood filler lets it sand flush with the surrounding wood.
- Wood putty sands less evenly due to its soft, gummy composition. Putty will sand down, but not as uniformly smooth. Unique filler ingredients impact sandability.
Superior sandability makes wood filler the better choice for repairs that require an ultra-smooth finish.
Color Matching
When selecting wood filler or putty, also consider its ability to blend with the color of the wood:
- Wood filler comes in a wide range of wood shades to closely match different stain colors. Grain-filled types help blend repairs into the wood grain.
- Wood putty looks best on natural, porous woods where the oil can penetrate and match the wood color. Putty works for clear finishes but not for stained wood.
For repairs to stained or painted wood, wood filler offers better color-matching capability to seamlessly blend repairs.
When to Use Wood Filler vs. Wood Putty
With all of these factors in mind, here are some general guidelines on when to choose wood filler or wood putty:
Use wood filler for:
- Filling holes, cracks, gouges in finished or unfinished wood
- Repairing trim, furniture, cabinets, woodwork
- Matching repairs in stained or painted wood
- Projects where durability and hardness are needed
- Quick repairs and fast drying time
- Smoothing repairs flush with fine sanding
Use wood putty for:
- Filling small nail holes and defects in raw, porous wood
- Matching repairs in natural, clear-coated wood
- Projects where flexibility is needed
- Slow drying permits more working time
- For an inconspicuous, natural-looking blend into wood
Advantages and Disadvantages
| Product | Advantages | Disadvantages |
|-|-|-|
|Wood Filler|Dries hard and durable; Wide range of colors; Sands smooth; Dries fast|Not as flexible; Doesn’t blend as naturally|
|Wood Putty |Flexible; Blends into unfinished wood; Slow drying time; Easy to apply | Not as durable; Limited color options; Doesn’t sand smoothly|
Key Takeaways: Choosing the Right Wood Filler Product
- Wood filler and wood putty have different compositions and properties optimized for different applications.
- Wood filler works best for durable repairs to finished or unfinished wood where coloring/staining is needed. It dries fast and sands smooth.
- Wood putty excels at small defects in natural, porous woods where flexibility and inconspicuous blending is desired. It allows more working time.
- Consider where the repair is, the condition of the existing wood, the finish, the need for color-matching, and the desired drying time and durability.
- Test products first to ensure they provide the desired working properties, dry time, sandability, finish, and color-matching.
- For flawless wood repairs, choose the product that’s formulated for your specific project requirements.
Frequently Asked Questions
What are the main differences between wood filler and wood putty?
The main differences are in their composition, best uses, durability, drying times, sandability, and color options. Wood filler is composed of solids like sawdust and binder material that dries hard. Wood putty uses oils like linseed oil to form a flexible, putty-like material as it cures.
Wood filler works best for repairs to finished wood that require staining and paint that need to be durable and sand smooth. Wood putty works best on natural, porous wood to inconspicuously blend repairs and provide flexibility. Wood filler dries much faster, while wood putty allows more time to work it.
Can wood putty be used to fill large holes?
Wood putty is designed for filling smaller holes, scratches, and nail holes. It may not be the best choice for large holes or cracks in wood, as it remains somewhat flexible when dry and lacks the durability and hardness of wood filler. For deep or large repairs, a wood filler formulated for gap filling would be better.
Is wood putty waterproof?
Wood putty is water-resistant but not fully waterproof. Since it contains linseed oil or similar drying oils, prolonged exposure to water or moisture can cause wood putty to soften and eventually fail. It provides moderate water resistance for small repairs, but wood filler or epoxy would be more durable and waterproof.
Can I use wood filler to patch drywall?
Wood filler is designed for repairing wood materials only. It will not bond effectively to drywall or provide the sandability and smooth finish needed for drywall repairs. For drywall repairs, use a patching compound formulated specifically for drywall and plaster.
What can I use if I need colored wood putty?
Since traditional wood putty only comes in limited natural wood colors, using a wood filler is the better option when you need to match a colored stain or painted finish. Wood fillers come in a wide range of wood tones to match different stains. Grain-filled fillers help blend the repaired area into the surrounding wood grain as well.
Can I stain over wood filler or wood putty?
Wood filler is designed to be stains and painted over for closely matching repairs. Most types of wood putty are not designed to be stained, as the oils prevent the putty from absorbing stain properly. If staining repaired areas is needed, a wood filler that matches the stain is a better option than wood putty.
Conclusion
Wood filler and wood putty each have characteristics that make them ideal for certain situations. Wood filler suits repairs that need to be durable, sdandable, and match surrounding stained or painted wood. Wood putty fits applications requiring more flexibility and where matching the natural color of unfinished wood is desired. Consider where the repair is, the existing wood’s finish, the scale of damage, and the desired working properties and drying time needed to choose the right product for flawless wood repairs. Testing products first on scrap wood is recommended to ensure they provide the expected results.