Ultimate Guide to Wood Warping and How to Fix It


Wood warping is common, and woodworkers who have had the displeasure of working with warped wood know how much of a morale killer it can be.

Before we proceed, we’d like to state that all boards are liable to bow, whether hard or soft, green or dry. This is because the rate at which moisture leaves the wood fibers is uneven.   

Therefore, the more exposed sides to heat and air would dry faster and shrink quicker than those with less exposure. This absence of uniformity distorts the general lay of your boards, causing an initial flat panel to become bent. To prevent warping, selecting a good board is quite crucial.

Fixing warped wood is all we are about in this article. First, we’ll show you that warping is not impossible to fix. Then we’ll provide you with all the essential information you need to tackle warping.

How do I stop my MDF from Warping?

There are several ways to avert the warping of your MDF panels. Here are some of them:

Proper storage

Proper storage and handling of MDF sheets is essential in maintaining their inherent flatness. MDF boards are pretty heavy, causing them to buckle under their weight if not handled or stored correctly.

The best way to store MDF sheets is to lay them on flat pallets or support them with sufficient bearers.

Tips to remember when storing MDF sheets

Here are seven tips to remember when storing and handling MDF sheets:

  • Ensure they are stored horizontally. MDF sheets are very dense and can topple due to their weight if stacked vertically.
  • Keep them above the ground on supports and in a cool and dry place. This support helps keep the sheets clear of the ground. They must be of equal sizes and spaced equally beneath the sheets. We recommend that you use at least three bearers.
  • Another thing you can do is place a sheet of polythene beneath the sheets so they don’t have direct contact with the ground. This would protect against additional moisture seeping into the wood from the floor. 
  • When stacking the panels, make sure the edges align to prevent any side from hanging over the other. Also, keep the edges flush and neatly arranged.
  • You can additionally store MDF sheets vertically, provided you only deal with a small number of sheets and ensure that they are adequately supported. You can build a rack for them if you want. This helps to keep the boards flush and flat.
  • The storage area must be well-ventilated and dry. Relative humidity of about 50% RH should suffice to keep the moisture content in the boards within a range of 7-9%.
  • When storing multiple layers of MDF panels, place one or two vertical boards above each layer to balance any inconsistencies caused by acute changes in the environment and its conditions.

Adequate framing

MDF sheets are very dense and heavy. This makes them very susceptible to bending under increased weights, their weight, and added weight.

Reinforcing MDF panels helps lower the risk of warping and sagging. So good framing helps keep flat surfaces dead flat; this way, you won’t need to worry much.

One way to do this is to reduce the spacing between supports or avoid over-loading the sheets like shelves and cabinets. Proper framing will help provide structural integrity and reduce sagging if your project demands strength.

Waterproofing the sheets with oil

The oil method is one effective way to make your sheets waterproof. Natural oils in wood dry out over time, so adding oil replaces the lost oil. They reinforce the protection and resistance provided by the natural oils in the wood while nourishing and enhancing its appearance.

The different types of oil suitable for this purpose include boiled linseed oil, teak oil, mineral oil, tung oil, walnut oil, and Danish oil. These oils offer some protection against moisture, insect attacks, and other elements. However, they are not as protective as lacquer or polyurethane.

Danish oil offers the best protection because it is a mixture of oil and varnish. And so, it is much stronger.

How to waterproof your MDF sheets with DIY oil

You can also formulate your oil treatment by mixing 1 part of linseed oil (you may also use teak or tung oil) with I part of turpentine and ½ parts of apple cider vinegar.

First, wear the necessary protective equipment like rubber gloves, respiratory masks, eye goggles. Next, sand the boards with fine-grit sandpaper or sanding pad, then wipe off any dust or debris using a tack cloth. Finally, apply the oil with a rag carefully on the wood.

Leave it dry for roughly 30 minutes, then wipe the excess off using a dry clean cloth. Allow curing for 24 hours. Then sand down the surface using excellent steel wool. After this, you can apply multiple coats, repeat the application, drying, and sanding.

Sealing the sheets

Since MDF is a highly porous material that soaks up liquid like a sponge and swells, sealing is essential to prevent your sheets from absorbing too much moisture and becoming damaged.

Sealing entails handling various chemicals and products, most of which are neither harmful to the skin nor irritating the eyes or throat. But it is always better to be safe than sorry.

Tips for sealing MDF sheets

Here are some tips to remember when sealing MDF sheets

  • Always work outdoors or at least in a well-ventilated area.
  • Ensure you put on protective equipment like gloves, a face mask, eye protection, and an overall before you begin.
  • Cover the ground and any object close by with polythene sheeting. You can also use a drop cloth if you have that. This way, these surfaces would be protected from dust, paint spills, and other chemicals.
  • Lastly, when you are done, dispose of the materials used properly.

Using moisture resistant panels

Some MDF products are specially designed to resist moisture-related damage. These types have water repellents added during fabrication. If you want to use MDF panels for your bathroom and kitchen projects, they are your best bet. The water resistance these sheets provide varies according to the different humidity levels.

How to Flatten warped MDF

There are several different ways to fix warping. These methods are tested and trusted by experts. The principle is simple: apply additional heat and moisture to the reverse side of the warp. Here are ways to flatten warped MDF.

Applying heat

Heat is very effective when trying to unwarp wood. All you have to do is get a heat source and follow these steps;

Step 1: Clamp the MDF sheet to a flat surface. You could use the floor or a large flat table.

Step 2: Apply heat to the board. While doing this, increase the pressure in the areas affected the most. Do this until the board gets very hot.

Step 3: Then, slowly bend the bowed sheet in the direction of its original shape and give it time to cool down.

You’d find that doing this would help return the warped sheets to their natural state.

N.B: Be careful not to apply excessive heat as this can damage the sheets.

Using a steam iron

Another way you can flatten warped MDF sheets is using a steam iron. Do not use a dry iron. Follow these steps when using a steam iron to flatten MDF.

Step 1: Wrap the sheets up

Use one or two large towels or rags to wrap the deformed sheets completely. Ensure that the affected area is covered with towels. The towels or rags must have been presoaked in water to moisten them but not excessively. Wring out excess water if necessary.

Ideally, the towels should be big enough to wrap the whole board so that no area is left bare. The towels or rags you’d use must be able to bear the iron’s heat without burning.

Step 2: Place the workpiece a flat surface

After wrapping the sheets with the towels, put them on a flat surface like an ironing board. This surface must also be able to bear the iron’s heat. Ensure that the concave surface faces down and the affected area, i.e., the part raised like a bubble, faces up.

Step 3: Set up and iron

Set the temperature to the highest. After about two to three minutes, the iron should be scorching. Then, press it down firmly on the affected area and glide it over the whole surface of the sheet.

While doing this, apply pressure, especially to the warped area. Hold it for about five to ten minutes in between spots while gliding the iron over the surface. This would ensure that enough heat and pressure get to the wood.

Step 4: Repeat step 3

Do this over as many times as possible while checking if the deformity is corrected. Stop once you achieve the desired results. If not, repeat until the warp gets flattened.

Step 5: Finish up

Once you attain your desired results, unplug the iron and set it aside. Finish by unwrapping the sheets and allowing them enough time to dry.

N.B: This method may not work for all wood types. If you find no improvement after adopting this method, either the steam iron is not hot enough, or you need to try another method.

Adopting the Frankenstein method

This method is a little tedious, but it is reasonably practical, especially if you are fixing a lot of warped sheets. The principle here states that you need to reduce the internal forces within the wood causing the warping, thus relieving the fibers of these stresses. Here are the steps on how to do this:

Step 1: First, face the top surface and mark “X” on the bottom surface, now facing up.

Step 2: Next, clamp the deformed sheet firmly to your worktable.

Step 3: Set the depth of your circular saw to about ¾ of the thickness of the wood. Then, make some parallel cuts along the long direction of the board. Usually, two cuts should suffice, but this depends on the severity of the warping.

Step 4: If, after making the parallel cuts, the board flattens, stop here. Get rid of the dust residue using a vacuum and go to step 8. However, if there is still considerable warping, you may need to make more cuts.

Step 5: Suppose the board has some tight circular grain, spike knots, or other complications. In that case, these are the factors creating severe bowing or twisting. Then you’d need to make some additional cuts.

Step 6: Clamp the sheets down again and make the parallel long cuts. Then make additional cuts. This time they must be perpendicular to the spike knots. This would help relieve the tension and facilitate flattening.

Step 7: Unclamp the sheet and check if the defect is corrected. If the fault isn’t corrected yet, you may need to make more perpendicular cuts.

Step 8: After completing the cuts, you can proceed with the specific steps your project entails, such as planing, sanding, gluing.

By reducing internal forces, these cuts also reduce the structural integrity of your sheets. So, if your project demands that, you would need to reinforce the strength by adding more internal force. Here’s how:

Step 1: Cut a flat thin board of the same species into small-sized wedges.

Step 2: Next, create hollow cuts using a router perpendicular to the cuts already made across the spike knots as much as is required.

Step 3: Apply some glue and fix the wedges into the hollow cuts. Once you do this, apply glue to specific points along with the parallel cuts and drive some wedges into these spots using a hammer. Leave the glue for about two to three hours to set and dry.

Step 4: Trim off the excess from the wedges and unclamp the sheets. Now it is strong, flat, and ready for use.

The cuts will push the contracting and shrinking fibers apart. This will leave the wedges to add residual forces in the opposite direction, thus further widening the push while countering the forces generated by the warping wood fibers. This method facilitates flattening while restructuring the sheets.

Applying pressure

Out of all the methods for flattening warped wood, using pressure is the most effective and less stressful, making it most preferred. Here are the steps to repairing warped wood using pressure:

Step 1: Cover the Warp

Use some moistened paper towels to cover the inwardly curved surface of the wood. You can also use steam towels or paper in lieu. Whichever material is used, ensure they are damp enough and wide enough to cover the affected area.

Do not use dripping wet towels. Instead, wring out the excess after soaking or rinsing in water.

Also, you do not need to drape the entire wood; just ensure that you place the wet towels only on the inwardly curved area of the wood. This guarantees that the moisture will be concentrated in that specific area and directs the flattening process. This way, the outwardly bend side would lose water while the inwardly curved side would absorb more.

Step 2: Wrap with Plastic

Now, you’ll securely wrap several sheets of plastic around the wood and wet towels. It must tightly wrap the wood all the way to reduce the rate of evaporation and retain moisture for a while.

Step 3: Secure the Wrapped Wood

Securing the wrapped wood is the next step. To do this, clamp the wood sheets, applying enough pressure to secure them but not too much. Over-tightening may cause the wood to split, and this becomes more damaged. So you have to devote much care to this step.

Step 4: Store the Sheets

Leave the wood in that wrapped and clamped position for about a week. Then, check the progress regularly to see if it gets flattening or damaged. If you notice the latter, unclamp immediately.

The storage area should be as hot as 1490F (650C) for this method. Use a heat lamp or warming mat to attain and maintain this temperature. You can also choose to keep it under the sun directly or an electric blanket.

Whichever way, the exposure period should be about six to eight hours each day. After this time has elapsed, unclamp and unwrap the wood. Allow it to dry completely.

Check if the board is flattened and dry. If yes, it is ready for use. With this, you do not need to apply more pressure.

If the warp is still present, rewrap and reclamp the wood and leave it for a more extended period; two weeks or thereabouts. Reduce the temperature to about 770F (250C). Ensure the storage room is dry and not humid.

After the set period, unclamp and unwrap the sheet, then dry it. Now it is all set and ready for use. If the warping persists after this, the damage is likely beyond repair.

Using sunlight

The sun is the primary source of heat, and so it can be employed in unwarping wood. Using sunlight is not as effective as pressure, but it is also a confirmed method for repairing warped lumber. In situations where the bend is slight, you can adopt it.

Step 1: Wrap the board

Start the repair process by wrapping the board with damp towels; use as many as possible. You can also use rags instead. Just ensure that the material is large enough to wrap the entire board completely.

As with other methods, do not use wet towels or rags. Ensure you squeeze out the excess water.

Step 2: Place Under the Sun

Next, search for a warm area that receives a decent amount of sunlight during the day. Next, place a waterproof material like a plastic tarp or a large plastic bag on the ground. Then put the wrapped sheet on the waterproof material. This material will prevent moisture from seeping into the wood from the ground.

N.B: This method works best in seasons with long hours of sunshine, i.e., warm, dry weather but not in cold or wet conditions. Instead of directly on the ground, a solid surface like a deck or a driveway can be used.

Keep the wood directly under the sun this way for close to two days or more. This depends on the extent of the deformity. During this period, keep the board damp by spraying the towels regularly with water. Spray enough to keep the towels damp but not to drench them.

The sun’s rays facilitate the absorption of moisture by the wood. And as that happens, the wood will gradually bend back to its original state. Store the wood in a warm room at night with the concave side facing down.

The period of flattening depends on the severity of the warping. Check the progress regularly. Once it is fixed, unwrap the sheet and allow it to dry completely.

If you do not see any progress after two to three days, it means something is wrong. Either you are missing a step, or you need to try another method.

How Long Does it take to Unwarp wood?

The period of unwarping wood depends on the severity of the deformity and the method employed. For example, the Frankenstein method takes a couple of hours. For other ways, time could stretch into days and even weeks.

 

Does MDF warp when painted

Sealing MDF sheets with wood confers significant levels of resistance against warping. As a result, it is one of the most common sealing methods for wood products. This is because paint seeps into the pores in the sheets and fills them up, giving you a smooth glossy finish on the surface.

Painting or other sealing methods is essential for MDF panels for two significant reasons. First, it enhances the appearance and texture of the sheets. The truth is MDF is beneficial but not aesthetically appealing unless you coat it with paint.

Asides from this, it makes it more resistant to moisture-related damage and stresses. Before you paint, you must prime. Or else, you’d cause irreparable damage. It would only be a waste of time and effort to have your sheets bow as you apply paint.

Usually, one or two coats suffice, mainly working with enamel paint. But before applying the paint, ensure sand off the edges and get rid of any marks or blemish acquired during the sawing process from the sheets. Also, before painting, apply a primer coat.

How To Fix Warped Wood Table From Water

Water can easily be referred to as the sworn enemy of wood and its products. If exposed for a short while, the fibers start to buckle. If for an extended period, decay sets in.

Engineered products like MDF wood are also liable for water-related damage. Although they are designed to meet specific requirements, they are still made from natural wood parts and residues.

Being in a situation like this brings up how to fix it. It is not easy to repair a wood table or any project that warps due to water.

Take hardwood flooring, for example. If exposed to water for an extended period and decay has set in, replacing the damaged board is your best option.

You also have to remove any water source like leaky taps, sub-floor build-up of moisture, drainage problems, or anything that exposes your planks to water. So the replacements won’t start to buckle as well.

For minor cases of warping, you could do the following to get rid of the excess moisture in your panels:

Step 1: First, dry up the area using a towel and clean it using a good disinfectant.

Step 2: Use a vacuum to dry up the area thoroughly. You may even use an electric fan to accelerate the process.

Step 3: Then, dehumidify the room for at least 24 hours.

In such situations, the planks may bend back to shape if the moisture is taken care of.

For more severe cases, this may not work. Prolonged exposure causes extensive buckling of wood panels that cleaning and drying can’t handle. Instead, you should fix the water source and replace the deformed boards with new ones.

If you want to salvage the planks, you may want to consider this intensive method:

Step 1: Removal

Depending on how severe the damage is, you may need to remove a part of the plank or the entire plank. Cut out the deformed part using a circular saw if it’s only a part. The cut you’d make has to be parallel to the damaged area.

Then chisel out the cut strip or the whole board in the case of total removal.

Step 2: Replacement

Now, measure and cut new planks into a size that fits the piece to be replaced, i.e., the cut strip or damaged part. The new board’s color, finish, and shine must be the same for an even, more consistent look.

Fit the new plank into the hollow. Position it well such that it fits perfectly. Spread on some wood putty and rub it into the wood properly. Get rid of any excess putty and sand down the surface. After this, you can refinish the board for consistency.

Ways to Seal MDF sheets

There are several ways of ensuring your MDF stays warp-proof when you seal the sheets.

  • Paint
  • Liquid latex
  • Lacquer
  • Epoxy sealant
  • Varathane
  • PVA glue

Paint

The most common sealing method for MDF panels is through paint.

Remember that you should never apply paint directly to your sheets, or else the fibers will soak up moisture from the paint and then swell. Instead, we recommend that when sealing with paint, you sand first, seal the edges, prime and then paint.

Required Tools and Materials

  • Personal protection like eye goggles, face mask, overalls, or clothing with long sleeves and gloves
  • Sanding pad or sandpaper
  • Sealer
  • Paintbrush, preferably with synthetic bristles
  • Paint roller
  • Putty knife
  • Polythene sheeting

Here are the steps in detail:

Step 1: Sand the sheets

Sand the top of your panels to get neither overly smooth nor rough surface. Sand using medium-grit sandpaper or a sanding block. Much dust is generated in this process so ensure you wear a safety mask and goggles.

Work in circular motions, applying light pressure as you sand the surface and the edges.

Step 2: Seal the edges

The edges of MDF sheets are more absorbent than the surface, so you must devote time and care to properly seal them; else, a great deal of moisture will seep into the boards through the edges.

You can use sealers like MDF edging tape, PVA glue, wood filler, oil-based filling primer, or drywall compound primer. Always make sure you leave no edge unsealed.

Step 3: Prime the sheets

After sealing the edges of your panels, it is time to get the boards ready for painting. You can use PVA glue, enamel primer, or a spray-on lacquer to prime.

Of these three, enamel primers are the most effective. Always make sure the color of the primer and that of the paint complements each other.

N.B: When sealing with paint, avoid latex or water-based primers. Also, do not use water-based glues. Opt for acid-neutral glues instead. This will prevent any water-related damage. Avoid natural bristled brushes. Rollers, synthetic paintbrushes, or spray bottles are better options.

Apart from paint, other seal products include liquid latex, lacquer, epoxy sealant, Varathane, and PVA glue. These finishing products insulate the exposed areas of the wood and prevent the entry of heat or moisture.

PVA Glue

PVA glue can seal both edges and surfaces of MDF sheets.

T properly seal the edges, spread thin coats of PVA glue with a roller or a plastic spreader. Make sure to spread it evenly and carefully to avoid build-up. You can use a spray bottle if you have one. The method is the same for sealing the surfaces of your sheets.

The goal is to have the coat as thin and even as possible.

When sealing with PVA glue, it is crucial that you avoid water-based products. Most glue types require dilution with water. Avoid products like these to prevent the MDF sheets from absorbing moisture from the glue and swelling. Opt for acid-neutral PVA glues instead.

PVA glue may also be used as rimers, but some brands are not as influential under paints as other types of solvent-based primers. 

After spreading the glue, allow it to dry. You may even sand down if desired. However, sanding thoroughly may destroy the glue coating. So avoid excessive sanding.

Primers

Primers such as oil-based filling primers and drywall compound primers are also excellent sealants to prevent warping in MDF.

For oil-based filling primers, you apply them to the edges and sand down when the coat is fully dry. For drywall compounds, you only need a thin application on the edges. Then you wipe off the excess compound, leave it to dry, and sand down. After this, you then apply a primer.

These two can also be used to prime the surfaces of MDF sheets.

Enamel primers are also effective as sealing agents. As with other primers, a thin enamel primer coat should suffice to avoid build-up as the product dries.

Whichever products you choose to use, ensure they are solvent-based and not water-based. The color of the primer must blend correctly with that of your chosen topcoat. Too many coats of primer may result in your project looking uneven and unprofessional.

Shellac

Shellac is easy to apply and dries quickly. It is used for antiques and other indoor furniture. Although its durability and waterproofing ability is not as high as that of polyurethane, it does provide a degree of protection and beauty to wood.

You’ll need a sponge, brush, or rag to apply shellac. The brush works when you are trying to get the tight corners done. For large surfaces, a brush or rag would suffice.

Start by dipping your brush, rag, or sponge into the can of shellac. Whichever material you choose, allow it to soak up as much shellac as possible, and then firmly apply the shellac to the surface.

Ensure you work across the board, one band at a time, and try to make sure that successive bands smooth out the edge of the last line. One way to achieve this is to keep the edge of each band wet as you apply it and work as fast as possible.

N.B: When sealing MDF with Shellac, we advise you not to interfere with the drying process. Also, there is no need to sand in between coats. Shellac is self-leveling. Subsequent coats will melt into the previous. If you don’t like the finish of shellac, you can apply another topcoat like lacquer or polyurethane.

Polyurethane

If you’ve been searching for a sealer that offers the protection and shine that your MDF needs, then Polyurethane is your best bet. Polyurethane is the most durable and hard-wearing of all finishing products that work for any type of wood. It is water-resistant and leaves a plastic-like outlook. It also delivers outstanding results regardless of how porous the board maybe.

In addition to this, you’ll find that Polyurethane provides excellent protection against moisture, insect attack, and other elements. Thus, it increases the lifespan of the MDF while enhancing its beauty.

Polyurethane can either be oil-based or water-based. Water-based polyurethane dries quickly but does not improve the look and feel of the sheets. Oil-based poly, on the other hand, takes a longer time to dry but enhances the appearance of the wood by adding an amber glow.

It has three levels of shine: Matt, Satin, and Gloss. With Gloss being the shiniest under light, Matt lacks any shine. Satin is somewhere in between the spectrum.

N.B: For MDF sheets, it is best to use oil-based polyurethane.

How to properly apply Polyurethane to MDF sheets

To apply polyurethane to your panels, you need

  • Polyurethane sealer
  • A bristle brush
  • Sandpaper (100-grit, 220-grit)
  • A utility knife, gloves
  • Respiratory masks
  • Tack cloth
  • Polishing compound

Step 1: Smoothen the surface of the sheets to be sealed using sandpaper. Get rid of dust and other residues using a tack cloth. Apply your paint or stain and leave for about 24 hours to dry thoroughly.

Step 2: Open the polyurethane can and stir using a wood stirring stick till you get a thin, even consistency. If too thick, add some mineral spirit to thin the polyurethane out.

N.B: Do not shake the can, or there’ll be bubbles.

Step 3: Spread the polyurethane on the boards using a brush. Applying them very lightly in long strokes is crucial to avoid uneven strokes. Or you can use a wipe-on polyurethane to skip worrying about the brush marks.

Also, we recommend using a foam brush if you can get one. You wouldn’t need to worry about brush marks because they are made of foam and have no bristles. Plus, it helps control the number of coats. If you have any line marks, you can easily smoothen them out.

Step 4: Leave to dry for some time. This depends on the type of poly and the weather conditions of the environment. Water-based poly dries within 2 hours, while oil-based poly may take longer, between 3-6 hours.

The first coat of poly will cause the wood grain to rise. Sand down the surface using a 220-grit sandpaper or sanding block and wipe off the dust residue using the tack cloth.

Then apply the second coat. Allow to thoroughly dry and apply more coats if necessary. Usually, two coats should suffice. Only apply a third coat if extra durability is required.

After the last coat of poly, cure for a full day before handling. It may take up to 30 days for thorough curing. Avoid leaving it to cure in areas with high humidity because high humidity slows down the curing process.

When using poly, precision is essential. Because it is thick and leaves a plastic-like finish, it may not be ideal for high-end furniture. But it is perfect for refinishing and sealing wooden projects, especially those frequently exposed to water and other elements.

Lacquer

Unlike other finishing products that require sanding in between coats, lacquer does not. Instead, successive coats adhere to each other because they are a chemical bond.

Lacquer requires an advanced level of expertise in the use of sealing agents. We do not advise the use of lacquer if you are an amateur. This is because it is a very high-performance finish. It dries very quickly and leaves a hard, durable finish. Therefore, any mistake made during its application would persist even in the finished products. And these mistakes are very unforgiving.

Lacquer is best applied using a spray gun. You can use a brush if you don’t have a spray gun. You just have to make sure you apply the coats as thin and fast as possible.

How to apply Lacquer finish to MDF

Step 1: Sand down the surface using a medium-grit sandpaper or sanding block. Get rid of dust and other debris from sanding using a tack cloth.

Step 2: The best way to apply lacquer is in long strokes as thinly and smoothly as possible. When painting, you can do a few back-and-forth strokes to even the coats, but for lacquer, you can’t. Doing that would lead to the “orange peel” and cause your work to be messy.

Step 3: Allow the first coat to dry completely. Once that happens, apply additional coats in the same manner. You may apply 3-4 coats of lacquer to your wood. However, only apply more if necessary.  

Sealing your sheets is relatively straightforward. Skipping a step or two will cause irreparable damages to your projects. Some mistakes are forgiving; some are not. Before settling on any sealing product, consider your desired result. Before fixing anything, ensure you seal the panels thoroughly.

What Wood Species is Least Likely to Warp?

No wood species is above warping. Some species, however, are less likely to warp than others. The degree of lumber warpage depends on the pattern of its grain and the type of species from which it was gotten. The straighter the grain, the more resistant it is.

Redwood is, by far, the least likely species to lose its flatness, according to the US Department of Agriculture. Its grain pattern is the straightest. It also has high tannin levels, a chemical that confers protection from moisture penetration and subsequent damage. And although it is pretty expensive and light, it is the most dimensionally stable of all as far as warping and shrinking are concerned.

Other species with high levels of resistance to warping are cedar and fir. These two are dimensionally stable and less prone to distortion when compared to other species.

How to Check If Wood is Warped?

Do you have some planks stored and wonder how to check if they have become warped or are still flat? We’ve got you on that. Some deviations are so glaring that a single glance to point out the deformity is all it takes. Some are subtle and may not be easily detected.

Here are two ways to detect such warping in lumber:

Method 1: First, place your plank on a flat surface like a large table. Then, press your hands down on it at the edges. If it rests on the surface without swaying as you press down, then it is flat. If any part or edge is raised, it wobbles when you press down on it.

Do this for all faces and edges of your planks.

Method 2: A square tool is another way to check for warpage. Pass the square along the width of the planks. If it glides uniformly along the surface of the plank, then the lumber is flat. If it doesn’t, you will notice a raised or depressed area that confirms that it is bent.

Method 3: Lastly, you can check for warping by using winding sticks. Lay these short, flat pieces of timber in pairs, one in front of the other, and observe them. If they align, then the board is ok. If they are skewed, then the board is bent.

Final Thoughts

Now that you know that warping occurs naturally in the wood, no wood product, natural or engineered, is above warping. We advise that you ensure your sheets are humidity-free and positioned in a well-ventilated area. Also, if warping eventually occurs, follow the steps outlined in this article. Lastly, always check your boards regularly because early detection of defects saves you much stress, time, and money.

Martin Swizz

Hi! This is Martin, I like to research, experiment, and learn new things related to wood carving and other kinds of woodworking.

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