When you build some of the best pieces that your imagination is capable of, the chances are high that you will be using plywood to help keep the costs down. However, bending plywood is a lot more complicated than bending other pieces of wood on the market.
To bend plywood without damaging it, you will need to use the layering technique to get thin pieces of plywood and then glue each layer onto the shape you need. Creating a thicker piece of plywood that is bent into the perfect bent shape you need.
There are many ways to bend wood; however, because plywood is a layering of different sheets of wood that are perpendicular, it is not so easy to bend. You will need to get a few special tools and have the proper setup before you start to get the best possible results.
What Are The Different Ways Of Bending Plywood?
In general, three ways are used to bend plywood, each with its advantages and challenges that need to be overcome. You will often find that people are not always willing to do the work required to bend plywood, as the work can far outweigh the reward.
Two ways of bending plywood do not damage the wood at all, which means we will look at the third most common way possible. Each technique requires many special tools to be used and can take several hours to do, even when you are just practicing how to do it.
Using Steam To Heat The Pieces
This is the most well-known way of shaping any wood to fit around a curve, heating the wood in a closed container using steam. This helps the internal structure of the wood be heated up and become mailable, allowing you to bend the wood in almost any shape on earth easily.
However, it is only possible to do this on smaller pieces with plywood as the wood grains are not all going in the same way. This means that when trying to shape larger pieces, you will have to get a steam container that easily approaches the size of a room that is constantly being steamed.
Thin Pieces Glued Together
When creating larger bent pieces using plywood, this is the recommended way of doing so, as you can create a strong structure bent into any shape. To execute this technique, you have to create a mold of the bend you want to make and then start layering sheets of plywood.
By doing this, you are creating a new piece of plywood that is as thick as you want it to be, making sure to alternate the way the grain is going. Most woodworkers will adhere to this technique as it is the fastest and most painless way of bending plywood into your desired shapes.
Using The Kerf Bending Method
This is the bending method that has recently become popular, but it does require that you cut into the plywood to get the best possible bends. However, the technique is done by cutting slits into the plywood with a few millimeters of space between each one, thinning out the wood.
When bent, the wood easily gives way, creating a clean bend from the outside, and can be used to create almost any bend you may need. However, this damages the plywood and requires a lot of trial and error before you can easily execute the bends perfectly.
What Tools Will You Need To Bend Your Plywood Without Damaging It?
Now that you know which techniques we will be focusing on, steaming the wood and layering it, we need to look at the required tools. You will need to use five tools in total when creating bent plywood; each one is rather basic but essential to the process.
Many people assume that you can use alternatives or try to use a shortcut to get around the problem. However, we have found that adhering strictly to using the right tools will allow you to have the best possible results when creating your bent plywood.
- Glue: No matter what you are doing with your plywood, you will need to use wood, and when bending plywood into your custom shapes, you need it more than ever. Normal wood glue will be able to do everything needed to bend plywood.
- A Mold: This is the trickiest tool you will need, and you will have to create it on your own according to the bend you need. You may get away with only creating a few skeleton shapes with the bend cut in, or you may have to make a complex skeleton piece that presses down on the wood.
- Clamps: It should go without saying that when you are gluing and bending plywood, you will need clamps. We usually recommend not leaving a single part of the piece without a clamp already on it, creating a piece that is as perfect as you may need.
- Heat: When bending thin pieces of plywood or slightly thicker pieces, we recommend having something to heat it. This helps the wood become more flexible when layering, ensuring that it does not crack if you put it under more stress.
- A Steam Box: If you are bending the plywood using steam, we recommend building a small steam box. This can be done with a kettle and a few pieces of spare wood, but we recommend only doing this when working on smaller pieces of wood.
How Do You Bend Plywood With By Layering?
Now that you have all of your tools ready and the extra glue bottles have been bought, we need to start creating a bent piece of plywood. However, this is not as easy as it sounds, as several things can go wrong when going through this process.
Many people that give up have made simple mistakes, causing the wood not to stick properly or for the wood to start cracking when bent. If you do everything correctly, you will be able to get a piece of wood that is perfectly bent without cracks and is structurally stronger than regular plywood.
1.Create A Mold
This is the first step to any bending process and will require you to think out of the box; sometimes, you can clamp the layers into a bend. However, sharper turns and more complex pieces will require that you have a mold that has been cut before you start the gluing process.
Using a router or a jigsaw, you can cut scrap pieces of wood into the bend you want; however, it needs to be the negative of the bends you wish to. By doing this, you can easily create a bend that is accurate to what you need and will easily provide you with an excellent structure to bend with.
2. Get Several Thin Pieces Of Plywood
The plywood you need to do this should not be thicker than seven to ten millimeters, usually just one sheet of plywood. You should have pieces that are either cut along the grain or are cut across the grain, which should be available from your hardware store.
Once you have the sheets, you can put the first one onto the skeleton you created before and then started layering everything from there. However, you will need to put down glue between each layer and clamp the newest layer down before simply applying the next layer to the piece.
3. Glue Pieces Together
As you apply each layer, you will need to add the glue; however, you need to add enough glue to ensure that every corner of the sheet has glue. The glue will most likely leak out the side of the piece you are creating; however, this means that their pieces have been married properly.
When doing this technique, you create a larger piece of plywood that is bent, which means that you need to have it glued properly. This requires more glue than you would typically use as the pieces are likely to be much larger than normal, which has more surface area.
4. Clamp Each One Down
It is important not to move too fast; you will have to stop and clamp each piece down thoroughly when creating the bent pieces. Clamping each new layer down and leaving the glue to be dry before adding the next bit, or else you will have pieces that are not properly married.
This is why creating a bent piece of plywood usually takes several days, depending on the size of the piece you will be creating. We always recommend using as many clamps as possible, ensuring that the wood has the same amount of pressure throughout.
5. Layer Until Desired Thickness
You will have to repeat the process until you have the piece as thick as you want it, waiting for each layer to dry thoroughly before you add the next one. By doing this, you can create a bent plywood piece that is as strong as you could want it without supporting it.
You mustn’t layer the pieces too much or too little, as this can create a piece that is not quite strong enough or bent enough. The thicker the piece is, the heavier it is, while thinner pieces may break when some pressure is applied.
How To Use Steam To Bend Plywood?
The layering technique is what we consider to be one of the easiest techniques when having to create a bent piece of plywood. However, you may want to use already existing pieces of plywood when creating your bent pieces, which requires you to use steam.
Steam can be one of the trickiest ways to bend your plywood, as it can be easy to go wrong, especially if the steam is not hot enough. To do this step properly, we always recommend using only smaller pieces of plywood that do not need such a high amount of heat and steam.
1.Create A Steam Box
The first step will always be to create your steam box, preferably out of wood, as most metals and plastics will not withstand moisture and heat. Creating a small steam box out of wood is the best way to create a complete seal that can completely prevent the steam from constantly leaking.
We recommend creating a steam box using a kettle; if you do not want to buy a proper steamer, the kettle will ensure the steam is hot enough. When doing correctly, you can easily heat any piece of plywood that fits in the steam box and make it easy enough to bend.
2. Steam And Heat Plywood For Several Hours
You will have to steam the plywood for several hours, with most people recommending leaving the piece in the steam box for at least 2 hours of constant steaming. Once you are done, you should remove the steamed piece of plywood and immediately move on to the next step.
Every moment the plywood gets to cool down is another moment it starts to set, which means that it may stay straight or start warping if not moved fast enough. Because plywood is a layering of wood, it can be much more resistant to being bent than any other type of wood.
3. Repeat Mold Steps
Once you have steamed the plywood, you need to put it onto the skeleton mold you have made and start clamping everything into place. The steps to creating a mold and getting the plywood into the shape are similar to the layering, which means you can use the same skeleton.
However, you will have to leave the plywood in the mold for at least 24 hours, with many artisans leaving the piece on the mold for an entire weekend. This ensures that the piece has fully accepted the new shape that it has to be in and that it won’t spring back to its previous shape as soon as the clamps are removed.
To bend plywood without damaging it, you will have to be patient, as the entire process can take most of a week. Many people will make plywood bending a specific part of the building process, setting out a week or more to ensure that all the pieces are made at once.
Whatever you do, please don’t try to use a heat gun on half-inch thick plywood to bend it; the results will be splinters and tears!