Polyurethane is a protective finish that is available in both oil based and water based forms. It comes in 2 varieties - glossy and satin finish.
Water based polyurethane is famous for being low odor and low toxic. It is transparent as compared to the oil based version which has a slight color.
The water based version also dries much faster. Water based polyurethane is good for things that are not exposed to extreme or rigid temperatures such as picture frames, side tables, bookcases and desks etc.
Water Based Polyurethane For...
- Side Tables
- Picture Frames
- Book Cases
Oil based polyurethane is comparatively more durable than water based especially when it comes to handling extreme heat.
It brings about the richness of wood but can add a slight yellowish tint.
Kitchen tables and wooden flooring are good candidates for oil based polyurethane. Both oil and water based versions can be applied on acrylic/latex paints.
Oil Based Polyurethane For...
- Kitchen Tables
- Wood Flooring
- Surfaces that may get wet
Polyurethane is available in either spray on or wipe on form. If you are not concerned about yellowing of the surface, polyurethane is the best option.
Top Rated Finishes:
Here is a video from Minwax that shows both finishes in action:
Pros Of Polyurethane
- Adds a Shiny Coat
- Virtually Scratch-proof
- Extremely Durable
Polyurethane is like melted plastic. Once hardened, it forms a strong protective shell over wood.
Moreover you cannot dispute the shine that polyurethane layering gives to expensive wood furniture and wooden flooring.
Polyurethane finish is hard and durable and is scratch proof.
Cons of Polyurethane
- Takes a long time to dry
- Needs Ventilation - Toxic and Flammable
It takes approximately 12 hours to dry so the drying process is long
While working with polyurethane, you have to make sure that the room is well ventilated. The reason being that polyurethane is highly flammable and toxic.
Polyurethane Application Tips:
Sand your piece with fine grits of sandpaper
Once the wood is free of blemish, remove any dust
Dilute your oil based polyurethane with mineral spirit and apply long even strokes of the liquid on the surface. Be sure to catch and even out any drips.
Use undiluted varnish to do the second and third coat and let dry for 24 hours
Once the surface is completely dried, cut away any drips with a razor evenly
Brush the final coat within 48 hours of previous coatings. Use the same care with the final coat too.
Polycrylic is water based protective coat. It is available in high gloss and satin finishes. It can be applied with a spray bottle or roller. It offers protection of wood along with faster drying times. It adds beauty to interior wood pieces such as furniture, woodwork, doors and cabinets. It is ideal for use on light wood surfaces like ash, maple, birch because it has no tint. It also works well over water based wood stains.
Pros of Polycrylic
- Very Affordable Product
- Easy Clean-up
- Durable Finish
- Clear finish - particularly on lighter shades
Polycrylic is very affordable and readily available at hardware stores.
Polycrylic creates a durable finish and is great for surfaces that are very frequently used such as desks, kid’s furniture and tables.
It is completely clear and does not have a yellow tint like oil based polyurethane. So it is best used when you don’t want a yellowish colored layer over your furniture and more so over light colored paint.
Tidying up is super easy because it is water based. Simply clean your rags, hands and brushes with water and soap.
Cons of Polycrylic
- Runny Consistency, challenging to apply well
- Dries very fast - hard to work with large pieces of wood
- Milky finish if applied too thickly on dark paint
It works well over standard latex paint but not over matte latex. The additives in matte paint keep the “easily dried” polycrylic from drying up. It remains runny leaving behind cracks when dried.
Due to its runny consistency, you will have to apply very thin coats on vertical surfaces and watch closely for drips.
Once you have applied a coat, you can’t go back to re-do it as it will make your surface an untidy sticky mess.
Difficult to use on large pieces because it dries really quickly.
Polycrylic is actually opaque and not transparent. Over dark colored paints it can give a milky finish if applied too thickly.
Polycrylic Application Process:
First make sure the surface is free of dust. Debris trapped up in polycrylic will create an uneven finish.
Sand very lightly using sand grit paper
Apply a thin layer of polycrylic with a foam or soft bristled brush and let it dry
Sand again using grit paper
Apply two more coats.
WHICH ONE TO USE?
There is no standard answer when it comes to deciding which poly to use. It all depends on three things:
1. How the piece or surface will be used. Usually high traffic pieces like kitchen table would be better finished off with polyurethane while a white lamp in the master bedroom should be done with polycrylic.
2. Will it be exposed to water? Consider oil-based polyurethane
3. Does it need to dry quickly? Take a look at polycrylic