How to stop sap from coming out of wood? Fresh wood deck boards and furniture look fascinating and bring a perfect vibe to your design. However, it lasts as long as you notice sap coming out of the wood surface. Instead of that stylish look, you have to deal with the sticky tree sap oozing out of the wood.
Don’t be desperate! Here is a simple guide on how to stop sap from coming out of wood by six steps.
How to stop sap from coming out of wood?
When you see sap leaking out of the wood deck boards, it looks really frustrating. However, when you know what to do the problem is not so scary.
The wood units that leak sap can be treated so that you can remove, stop, and prevent the new leaking issues.
Now, let’s find out more about the ways to stop tree sap from coming out of wood surfaces!
What tools and items do you need?
To start removing sap from the wood, get the tools and items from the list below:
- Protective gear (face mask, rubber gloves, protective glasses)
- Heat gun
- Thin and sharp tool (chisel or putty knife)
- Turpentine or alcohol-based substances
- Sandpaper
- Wood stain
- Sealer
- Paintbrush
- Clean cloth
Step #1 – check the sap state
Before you start, touch the sap coming out of the wood to check its state. Knock at it to check if it is hard and brittle.
If the sap is already dry and hard, you can proceed with the third step. In case the sap mass is still quite soft, or there is liquid sap oozing out of the wood surface, you have to harden it before removing it.
Step #2 – harden the sap
The easiest way to remove sap that is coming out of wood surface is to harden it. When you try to remove liquid leaking sap, you can make even more mess than you already have!
If your wood surface is not properly dried, it can be a cause of sap leakage. So, you need a heat gun to fix this situation!
The best way to stop sap from leaking outside and make it easier to fall off the wood surface is to crystallize it. Since you need high temperatures to get this result, use a heat gun to turn liquid or soft sap into crystals.
Set the heat gun up to the proper temperature. The settings can vary depending on the exact type of wood you have. As a starting point, switch your heat gun on at 140 °F, and then you can raise the temperature if necessary.
Then, keep your heat gun moving over the affected areas. Don’t keep it working in the same spot for too long, as you can leave a burn mark on the surface. Proceed with heating the sap as long as you need to make it completely dry and hard.
Step #3 – remove all the sap crystals
Now, when you manage to stop sap from coming outside the wood surface, and it is hard enough, it’s time to remove sap crystals from the wood.
If there are big sap chunks solidified on the wood surface, you can break them away just by hand. Use protective gloves to prevent hand injuries!
Then, deal with all the excess sap that is left on the surface. There are smaller crystals that are hard to remove, so you need to scrap them away with a thin and sharp tool. Use a chisel or a putty knife to chip the hardened sap mass away from the wood.
However, be careful so as not to damage the wood surface! Keep the scraping tool parallel to the wooden surface to avoid any damage to the wood structure.
Keep scraping until all the sap crystals fall off the wood unit. You need to dispose of as much hardened sap as possible.
Step #4 – get rid of the liquid sap
After removing hardened sap, there can be still some liquid residuals that didn’t harden after heating. However, don’t be afraid that some sap is still leaking outside! It is pretty easy to remove with the help of some household chemicals.
Turpentine is the most popular remedy as it doesn’t affect the wood structure. Use some turpentine to dissolve the liquid residuals of leaking sap and remove them from the surface.
Apply some turpentine on the sap residue and let it work for a while to dissolve it. Then, take a coarse sponge and scrap the softened sap away from the wood. For a final touch, moisten a clean cloth with some turpentine and wipe away all the residue from the wood.
As a good alternative, you can use mineral oil or any alcohol-based solvents. For example, such simple household products as hand sanitizer, white vinegar, or mineral spirits can do this job for you!
As soon as you clean sap residue, let the wood dry completely before the next step. You can’t proceed doing the next steps while the wood is still damp as it is not possible to sand adequately. Moreover, the wood that is not dried properly is prone to swell or warp.
Step #5 – sand the wood surface
While you are scrapping the hard sap chunks, no wonder you accidentally destroy the integrity of the wooden surface. In other words, sharp tools like chisel or putty knives can leave some scratching marks on the wood. This is definitely not what you want to see, though.
However, don’t panic! Any scratches and imperfections can be removed if you give the affected areas a good sanding help.
Sanding is an essential step that makes your wood project look smooth and shiny.
Check the surface to be sure that everything is completely dry and clean. Even the smallest sap residuals can stick and clog the sandpaper up. As a result, you won’t be able to use it anymore. Moreover, you can spread the liquid residuals all over the nearby surfaces of the wood unit. Thus, you will get a splotchy surface that looks very awkward.
In addition, never sand the affected surfaces that still have sap mass on them! Although some people hope that sanding helps to remove sap better, that is a big mistake. Along with damaging your sandpaper, you turn the sap into sturdy gum that is even more difficult to get rid of. So, be sure that you work with the perfectly clean wood!
The coarseness of your sandpaper depends on the size of the scratches you want to dispose of. Start sanding with a coarser sandpaper to remove bigger scratches from the wood. As a rule, 80-grit sandpaper is a good starting point. Then, proceed with 120 and 240-grit sandpapers to fix the minor damage.
When you are done, clean all your projects thoroughly from dust and debris accumulated after sanding.
Step #6 – seal the wood surface
Finally, you have to prevent sap leakage from starting again. This step allows to block the wood pores that can produce more sap again.
Make sure to clean all the surface properly from the wood dust and debris. Any remained mess becomes awkward after fixing it with the sealer.
You can optionally stain the wood objects to make them look better. This additional step improves the sealing effect by clogging up the wood pores. Then, start covering the smooth surface with a good sealer. A good rule of thumb is to opt for shellac-based sealers that penetrate deeply into the wood pores and clog them tightly.
Cover all the surfaces with multiple layers of sealer, especially those with knot areas where you can face more sap bleeding again.
Then, let the freshly sealed wooden unit air dry completely.
If you are going to seal an outdoor deck, opt for a waterproofing wood sealer. It can not only prevent sap from coming out of the deck but also protect wood from swelling.
What makes sap bleeding out of the wood?
Freshly cut wood should always be dried properly. Here are two main types that you can meet:
- Kiln-dried wood
- Air-dried wood
Kiln drying is the most reliable way to treat the wood and stop sap from coming outside. High heat inside the kiln makes the sap sugars harden and crystallize, so the sap is fixed inside the wooden unit. As a result, kiln-dried wood is less likely to leak sap.
FAQ
Why does sap come out of treated wood?
Two types of mistakes can cause the sap problem: untreated green wood and wrongly dried wood.
Generally, this problem often depends on the wood type. Some types of wood are high in sap, so the leakage problem can happen more often and require more treatment measures. However, these two general causes are common for any type of wood:
• Wrong treatment is a common cause of a sap problem. Untreated wood is prone to having more sap coming from its surface since it is not sealed and dried properly.
• Another common case is related to the excess sun exposure. Too much direct sunlight can provoke sap leakage even in treated wood, so you need to take some extra measures to treat it again.
What’s the best thing to remove sap from wood?
For the hardened sap, the best option is to use a sharp and thin tool like a chisel to scratch it away. For the softer masses, use chemical or natural solvents that can simplify your task. Use mineral spirits, white vinegar, or even your hand sanitizer to dissolve the sap and make it easier to remove from wood.
How do you paint over wood sap?
If you have to deal with the sap leaking out of the painted wood, you can’t repaint the wood over the sap masses! The right idea is to clean and prepare the surface before you repaint it. A fresh coating of paint neither masks the sap mass nor stops it from leaking again.
The painted wood treatment guide includes the next steps:
• Find the knot areas on the painted wood that are prone to bleeding.
• Remove sap from these areas and let them air dry completely.
• If there is more sap that keeps bleeding from the knots, repeat the cleaning process until it stops appearing on the wood surfaces.
• Clean the wood with a solvent to get rid of the sap residuals.
• Wait until the cleaned areas air dry completely.
• Sand the dried wood knots thoroughly to fix any damage that you may leave while scratching the sap away.
• Clean the wood thoroughly from any dust and debris before sealing it.
• Cover the prepared areas with a shellac-based sealer.
• Sand the primed areas with a fine sandpaper to make the surface perfectly smooth.
• Clean the surface with a damp cloth after sanding, and let it dry completely.
• Now, apply two fresh coats of high-quality paint on the wooden unit.
What causes sap in wood?
In the wood world, tree sap works the same as animal blood. Containing two organic substances known as xylem and phloem, it feeds the tree and performs a transporting function.
When you use wood as a type of material, always remember that each piece of wood has a certain amount of sap inside it. So, if you want to prevent further sap issues, be sure that your material is dried and treated properly.
Final thoughts
As you can see, it is possible to stop sap from coming out of the wooden objects. Good sealing by shellac and waterproof substances will help you stop sap coming out of the wood.
