How wood finish - varnish or Seal ?
Taking part in craft workshops , I am often asked about the difference between varnish or seal a finished project. Both are excellent finishing techniques - when applied in the right circumstances.
Did you know that the internal structure of wood contains thousands of cells or microscopic tubes that go up and down the wood grain . These tubes carry nutrients that are essential for the growth of trees and , once cut and dried , they continue to expand and contract under conditions of high humidity.
Even after a synthetic finish was applied to the wood surface , wood continues to expand and contract according to external environmental conditions in which it is placed . This is not a process but you 'll notice there are clear signs that this is happening . In very humid weather, you may find that the outer door , garage door, or even a wooden door, will swell and paste, or you can fight to open a wooden window . This is because the wood has swollen (enlarged) because of excess moisture is absorbed into the wood. The wood swelled eventually dry out and return to its original shape , although sometimes a little sanding may be required.
Taking the above into consideration when deciding what finish to apply to your wood projects , it is useful to know some facts in advance.
What varnish ?
The varnish is a mixture of resins and oils that are applied to the wood surface to provide a protective layer against damage. The varnish is available in various formulations gloss and semi -gloss to a matte finish . The varnish most commonly used today is polyurethane varnish .
Nail does not penetrate into the timber , rather than the first coating layer blocks the wood surface to provide protection against ambient humidity. However , due to the constant expansion and contraction of the wood , over time the coating layer may crack and perish allowing moisture to enter the wood and further exacerbating the problem.
What is sealing ?
Sealer is a combination of resins and oils , but with a lower viscosity than the coating , which means that sealing actually penetrates into the wood itself to feed and protect the inside - rather than on the top. It is essential to apply three layers of sealant on wood surfaces , the first layer enters the timber , the second bond coat with the first layer to form a seal , and the third and last layer provides a surface that is heat , scratch and water resistant .
Sealant can be applied to almost any wood surface - indoors or outdoors - and there are different types of specially designed for indoor or outdoor conditions varnish. UV stabilizers are added to non-resident hunters to protect against sunlight and some even contain mold inhibitors and fungi. Before applying a sealant to your outdoor wood sure to check the label that the sealant meets all your local weather conditions.
Now we know the difference between varnish and sealant it makes a little more sense to finish we should apply to a particular project. Sealers are perfect for everything, varnish surface is better for interior surfaces where there is little chance of high humidity or moisture . For example, in a bathroom , laundry or kitchen.
Here are some tips for using varnish or sealer :
Do not wipe the brush inside of the box as it adds air bubbles and can ruin the finish of your project
Apply sealant or varnish the wood grain and work away from an edge for a smooth finish
Never apply too much or too little. If you have never done this before practice on a piece of wood to get the hang of it before you start your project
If the dirt (or bugs) marring the surface while it is still wet - let it. You will ruin the finish. Wait until the coat is dry and use the fine steel wool or 240 grit sandpaper to lightly sand the spot
Always wait until the first coat to dry completely before applying the second coat. A first adhesive layer and spoil you sand all down and start again
For a high gloss finish lightly sand between coats except the last layer
Taking part in craft workshops , I am often asked about the difference between varnish or seal a finished project. Both are excellent finishing techniques - when applied in the right circumstances.
Did you know that the internal structure of wood contains thousands of cells or microscopic tubes that go up and down the wood grain . These tubes carry nutrients that are essential for the growth of trees and , once cut and dried , they continue to expand and contract under conditions of high humidity.
Even after a synthetic finish was applied to the wood surface , wood continues to expand and contract according to external environmental conditions in which it is placed . This is not a process but you 'll notice there are clear signs that this is happening . In very humid weather, you may find that the outer door , garage door, or even a wooden door, will swell and paste, or you can fight to open a wooden window . This is because the wood has swollen (enlarged) because of excess moisture is absorbed into the wood. The wood swelled eventually dry out and return to its original shape , although sometimes a little sanding may be required.
Taking the above into consideration when deciding what finish to apply to your wood projects , it is useful to know some facts in advance.
What varnish ?
The varnish is a mixture of resins and oils that are applied to the wood surface to provide a protective layer against damage. The varnish is available in various formulations gloss and semi -gloss to a matte finish . The varnish most commonly used today is polyurethane varnish .
Nail does not penetrate into the timber , rather than the first coating layer blocks the wood surface to provide protection against ambient humidity. However , due to the constant expansion and contraction of the wood , over time the coating layer may crack and perish allowing moisture to enter the wood and further exacerbating the problem.
What is sealing ?
Sealer is a combination of resins and oils , but with a lower viscosity than the coating , which means that sealing actually penetrates into the wood itself to feed and protect the inside - rather than on the top. It is essential to apply three layers of sealant on wood surfaces , the first layer enters the timber , the second bond coat with the first layer to form a seal , and the third and last layer provides a surface that is heat , scratch and water resistant .
Sealant can be applied to almost any wood surface - indoors or outdoors - and there are different types of specially designed for indoor or outdoor conditions varnish. UV stabilizers are added to non-resident hunters to protect against sunlight and some even contain mold inhibitors and fungi. Before applying a sealant to your outdoor wood sure to check the label that the sealant meets all your local weather conditions.
Now we know the difference between varnish and sealant it makes a little more sense to finish we should apply to a particular project. Sealers are perfect for everything, varnish surface is better for interior surfaces where there is little chance of high humidity or moisture . For example, in a bathroom , laundry or kitchen.
Here are some tips for using varnish or sealer :
Do not wipe the brush inside of the box as it adds air bubbles and can ruin the finish of your project
Apply sealant or varnish the wood grain and work away from an edge for a smooth finish
Never apply too much or too little. If you have never done this before practice on a piece of wood to get the hang of it before you start your project
If the dirt (or bugs) marring the surface while it is still wet - let it. You will ruin the finish. Wait until the coat is dry and use the fine steel wool or 240 grit sandpaper to lightly sand the spot
Always wait until the first coat to dry completely before applying the second coat. A first adhesive layer and spoil you sand all down and start again
For a high gloss finish lightly sand between coats except the last layer
