Can You Plane Plywood to Reduce Thickness? (Should You?)

When you are about to start on a new woodworking project, the first choice you often have to make is the type of wood you will use. While the first thing that comes to mind is solid wood, it’s often too expensive and unnecessary for projects such as cabinets or simple storage containers.

Fortunately, technology has brought us a way to manufacture wood, allowing products such as plywood to be widely available at a lower price than solid wood.

That being said, due to the way it is produced, plywood behaves differently than solid wood and comes with a set of advantages and disadvantages of its own. For instance, solid wood is often considered to be more visually attractive. On the other hand, plywood isn’t susceptible to wood movement that often troubles projects made with solid wood.

With these differences at play, knowing what you can and what you can’t do with plywood can be hard to guess if you have no prior experience with it, which brings us to one of the most commonly asked questions about it.

Can you plane plywood to reduce its thickness, and should you do it?

While you can indeed plane plywood to reduce its thickness, we do not recommend doing so, as running plywood through a planer can cause damage to your planer in a few different ways.

Most commonly, the glue that holds the layers of the plywood causes the blades of the planer to go dull rather quickly, essentially rendering them unusable until you sharpen them, which is enough of a reason not to plane plywood in itself.

That being said, the issues related to running plywood through a planer don’t end there. Depending on factors such as the position you are planing your plywood in, you may face an extra set of issues alongside damaging the blades of your planer.

What Happens if You Plane Plywood?

Planing plywood is something that most woodworkers, beginner and enthusiast alike, won’t find pleasant, and there are good reasons for it.

While it’s possible to plane plywood with the correct tools and care in last resort scenarios, it often comes with more hassle than benefits, especially if you are new to the woodworking world.

With that, let’s get down to what happens if you plane plywood and why you should refrain from doing so.

Planing Plywood Dulls Planer Blades Quickly

The general sentiment is that planer blades and plywood don’t work well due to the glue that holds the layers of the plywood together. Since this glue is quite strong, planer blades usually have trouble cutting through it, which dulls them in the process.

While you can sharpen the dulled blades again, having to do so all the time can become quite a chore, which is why we recommend planing plywood only as a very last resort.

That being said, you may also hear some mixed opinions about this one as some woodworking enthusiasts believe that planer blades that are higher in quality don’t get dulled when used with plywood, which is something to keep in mind.

Planing Cross-Grain Can Clog Your Planer

Planing across the grain can often be unavoidable due to the way plywood is manufactured, which can quickly become a problem for your planer.

If you pay attention while planing cross-grain, you’ll notice that long strings of plywood are coming out, which eventually make their way to the dust collector of your planer.

As the dust collector is produced to accommodate small wood chips and not these long strings, they can easily clog your planer and cause you trouble if you aren’t careful.

Planing Exposes the Low-Quality Interiors of Plywood

As plywood is produced to be used as it is, the interior plies usually contain a lot of defects and holes that are aesthetically displeasing.

Using lower-quality plies on the inside of the plywood is one of the things that makes plywood cheap, which is common practice as it does not create a problem if you use your plywood without planing it.

On the other hand, when you plane your plywood, it’s almost certain that these lower-quality parts become exposed, meaning that you will have to take extra steps such as applying veneer or laminating it to make your plywood look good once again.

Planing Plywood Can Cause Veneers to Chip

Planing can cause the veneer on the plywood to chip and tear, creating an aesthetically displeasing look that will require extra steps to look good again.

As the core idea behind plywood is to buy it in the thickness you desire and use it as it is, it’s often not manufactured in a way that can stand a process such as planing.

How To Reduce the Thickness of Plywood?

While we don’t recommend planing your plywood for the reasons we have mentioned above, we understand that there are times where reducing the thickness of your plywood is your only option.

For scenarios where you are planning on reducing the thickness of your plywood as a last resort, here are two different methods you can use depending on your needs and the tools you own.

  1. Use a block plane. By using a block plane, you will be able to avoid electric planer-related issues such as blades going dull because of the glue or ply strings clogging the dust collector. With enough care and patience, it should also be possible to plane the plywood without chipping or tearing it. That being said, using a block plane takes a lot more time and effort than an electric planer, which can easily get out of hand if you need to plane large amounts of plywood.
  2. Use a power (electric) sander. If the amount of thickness you are looking to reduce is on the lesser side (less than half an inch), you can most likely get the job done with a sander. While this method requires much less effort than using a block plane, it won’t work well if you want to reduce the thickness by large amounts due to the amount of time it will take. We recommend using 180 to 220 grit sandpaper for this process.

After using either of these methods, you will most likely have to fix the surface of your plywood by applying veneer; or laminating, as it will look quite displeasing without doing so.

Can You Use a Block Plane on Plywood?

You can absolutely use a block plane on plywood and avoid the issues that come with using an electric planer on plywood.

That being said, planing with a block plane takes a decent amount of time and effort, which may not be worth it if you are looking to plane large amounts of plywood.

Can You Use a File on Plywood?

You can use a file on plywood without any issues, but the process may be pretty slow if the amount you’re looking to file off is too much.

As an alternative, you can use a power sander to achieve the same effect without putting in the large amounts of effort and time that filing requires.

Can You Round the Edge of Plywood with a Router?

You can round the edge of your plywood with a router, but you will need to take a few extra steps to ensure that it looks good.

When you round the edge of your plywood with a router, you will expose the inner layers of the plywood that don’t look very pleasant and can even have holes at times.

As a result, to make the new edges look good, you will need to either paint over them or edge-band them.

Wrapping Up

Even though planing plywood is definitely possible if you absolutely have to, it’s best to avoid doing so as much as possible due to the problems that come with it.

Considering that these problems range from damaging your planer to creating a suboptimal product, it’s often better to buy new plywood with the desired thickness instead.

That being said, if you really have to plane your plywood, remember to be extra careful, use the right tools, and take the process slowly rather than rushing through it.