Biscuit Joint Advantages and Disadvantages. Are They Worth It?

biscuit joiner
“File:Lamello-top.jpg” by Billbeee at en.wikipedia is licensed under CC BY 2.5

If you have been thinking about getting a biscuit joiner to enhance your tool’s arsenal, you probably noticed that there’s a lot of discussion on online forums about it being worth your money or not. A lot of people dislike them, saying they are completely useless. Like all the things you read online, you need to take them with a grain of salt. There are some truths, but also some misinformation. The best thing here is to evaluate objectively both the advantages and the disadvantages of the biscuit joint. After that, you can make an informed decision.

Here you have the quick answer. Let’s start with the pros. Biscuit joints are very simple and quick to make, perfect for beginners. You don’t need to be super precise either to get good results. If done correctly, they are a strong joint. They guarantee a clean, flush finish.

Now with the cons. You need a specific tool to do them. The biscuit joint is relatively strong, but it’s not suited for all woodworking projects. You need to be careful when trimming and sanding afterward to avoid exposing the joint.

So what’s the answer here? Are biscuit joiners worth it or not? Before answering with certainty, let’s talk about the biscuit joint advantages and disadvantages in detail. Let’s start with the pros.

Biscuit Joint Advantages

Simple and Quick

Biscuits joint are very simple to do, so they are perfect for a beginner who just started to get his feet wet. You don’t need to be super accurate to get a good result. There’s some wiggle room built in the slots to compensate for errors. There’s no need for precise measuring as it’s required with other types of joint. You probably won’t need to measure anything to make a biscuit joint.

This type of joint is as quick to do as it is simple. You can do a lot of them in a short period of time. They require two simple cuts, some glue, some clamping. Perfect for projects with not many claims. Don’t need to be super precise either as I said before. The biscuit joiner is very easy to use and needs minimal setup.

Clean and (relatively) Strong Joint

One of the main pros of biscuit joints is their look. If done correctly, they are very hard to spot, resulting in a clean and flush finish. They are also very good for alignment purposes. What about its strength then? It’s not the strongest joint of them all, but it’s definitely strong enough for a good amount of projects. I am referring to plywood-based projects, cabinetry, picture frames, etc. . To maximize its effectiveness, use a good water-based glue, put a good amount of it, and use as many biscuits as you can fit along with the board.

Talking about biscuits, they are very cheap, so that’s another pro. There are many sizes available, so they are suitable for all kinds of projects. More information about biscuit sizing here.

Biscuit Joint Disadvantages

We said that biscuit joints are very simple, but there’s also a variety of things that can go wrong. I’m referring to bad slots, uneven biscuit swelling, misaligned surfaces, just to name a few. Fortunately, these problems are very easy to avoid. Just keep in mind these tips I wrote about here.

Now, let’s talk about the cons.

Are Biscuit Joints Strong Enough?

We said before that biscuit joints are relatively strong, but they are definitely weaker than many others. Biscuits are just thin bits of compressed wood. When put in place, most of the resistance is carried out by the glue. On top of that, biscuits don’t go very deep into the wood. The biggest biscuit size available is #20, which is one inch large, i.e it goes half an inch deep in each board. All things considered, biscuit joints are anything but structural joints. However, they are a perfectly fine choice if you choose the right project. They perform the best with cabinetry stuff.

One Tool for One Job…

In my opinion, this is one of the strongest positions against biscuit joints. In fact, you’ll need to buy a biscuit joiner to cut the slots, and you’ll get to use the tool only for that type of activity. Think about other alternatives like the dowel joint, which is pretty similar to the biscuit joint, but more strong. In that case, you’ll need a drill, which surely you already have and use for many other things.

Basically, you need to evaluate if getting a biscuit joiner is worth it: how much are you going to use it? Are biscuit joints appropriate for the type of projects you usually do?

If you think you’ll gonna use it a lot, then it’s worth spending money on it. If you are planning on using it every once in a while, or you are on a tight budget, maybe consider using other types of joints.

Risk of Exposure by Sanding and Trimming

There are two aspects to consider here. Let’s start with sanding.  If you plan on sanding your project for a flush finish, make sure you wait until the glue is completely dry. If you sand over a biscuit before it’s completely dry, there’s a chance a depression is going to develop when the board around the biscuit also dries out. This is particularly important with thin wood when there isn’t much material between the biscuit at the surface.

Regarding trimming, there’s a risk of exposing the biscuit if it’s placed too close to the edge of the wood. This is especially true with side joints. There are two ways to avoid this. Plan the position of the biscuit joints carefully so that you won’t router over them later. Alternatively, make sure you keep enough space between the biscuit slot and the edge you will trim. Check the depth of the blade by testing on some scrap wood first.

In summary, both these problems can be avoided by planning in advance.

Final Thoughts: Are Biscuit Joiners Worth It?

biscuit joinery photo inside article that discuss biscuit joint advantages and disadvantages
“Biscuit joinery for middle shelf” by johnclarkemills is licensed under CC BY 2.0

As you can see, biscuit joints have both advantages and disadvantages. They are good if you need a quick and easy way to join two boards together. For a strong joint, there are probably better alternatives. I wouldn’t sit on a chair that has been built with biscuit joints, would you? Basically, it really comes down to the project you are going to perform. Some of them are more suited for biscuit joints than others.

So what’s with all the babbling on online forums about biscuit joiners? Most of the hate you read about online is due to biscuit joints being kind of a shortcut in woodworking. That’s because they are fast and easy, especially when compared to more traditional techniques like mortise and tenon. My take about this? You do you. I think one doesn’t rule out the other. With projects like bookshelves and picture frames, which don’t have many claims, biscuit joints are OK. On the other hand, you should learn and use more advanced techniques for finer projects.

Like all things in life, biscuit joinery has both pros and cons. It’s a good answer for some situations, not for all of them. All things considered, I think biscuit joiners deserve a place in a woodworker tool’s arsenal.