Polyester resin is a kind of waterproofing synthetic resin product that is widely used for purposes where water is the problem.
Presently there are also wood fillers made from poly resin that comes with poly resin advantages and can be used as an all-purpose filler for wood and other surfaces such as fiberglass, metal, cement, stucco, and others.
Two-part polyester filler can generally be used as a surfacing compound which allows you to fill screw/nail holes in wood along with any shallow scratches, which is usually the prepping process before finishing the surface with paint or stain.
The key advantage of using polyester filler (rather than putty), is it dries very hard, which makes sanding the wood pretty easy.
This also means that you can then match your surface, very well, with the other surrounding surfaces.
When filling the holes, dents, or scratches with a two-part polyester wood filler, keep in mind that it can shrink slightly when it dries.
So, it’s recommended that you should overfill the holes a bit.
If the gaps or voids are larger, consider applying 2 to 3 additional coats of polyester filler once the first filler coat dries.
Polyester Filler – Advantages & Disadvantages
Like any other product in the market, poly wood fillers come with benefits along with certain drawbacks.
The biggest benefit is it is non-toxic after it has dried and cured well on the surface.
The dust produced when the wood is dry-sanded is also non-toxic and less harmful than other products.
But keep in mind that if you sand the freshly repaired surface, without allowing enough time to cure the filler, it can be irritating to eyes, skin, and lungs because of the release of VOCs.
Polyester wood filler is also water-resistant and can be used at places where water damage or wood rotting is a problem.
But do not expect them to be a hundred percent waterproof.
Along with the pros, there are certain cons you should be aware of. These include:
- Comes with a high embodied energy
- Can be difficult to recycle and disposing of
- It’s a petrochemical substance that can be harmful for the environment and living beings
Is Polyester Wood Filler Same As Epoxy Filler?
Epoxy and polyester are not the same, but different.
Although both are excellent to use as a filling agent, epoxy being more flexible is a better product for filling wood surfaces.
Also, it adheres better than polyester-based wood filler products.
So, if you want a wood filler compound that does adhere well and is also stable and strong, epoxy should be your priority.
However, if you do not find the product available or want a cheaper alternative, the polyester filler can get the job done pretty well.
Keep in mind that these will be however less durable and can come off fast if you are using them on wood.
Douglas Becker (aka Painter Doug) has over twenty years of experience as a painter in Adkins, Texas. At present, he resides in Florida with his family.
From painting multi-storeyed houses, condos, and apartments to large commercial buildings and small offices, he had served various customers in areas not only in Adkins but also in Southwest Florida, Sarasota, Naples, and many more. To know more about him check here.