best biscuit joinery techniques

The Best Biscuit Joinery Techniques & Tips

Ever since the biscuit joiner was invented, the art of woodworking has been completely revolutionized.

Let’s admit it: nothing can match the abilities of a biscuit joiner when it comes to simple and fast carpentry. Just grind the connecting pieces, use glue, and slide the biscuits in place, assemble, hold and you’re done. After about a minute, your joint is fully aligned and strong enough for many applications, and the horizontal motion room provided in the joint, makes adjusting easy at the time of assembly, just when other ways of creating a joint would leave you high and dry.

With woodworking artists, hobbyists, and professional furniture makers from all-across the globe using a biscuit joiner in a large variety of projects, the need for efficient joinery techniques is inevitable.

 This article provides valuable information on using a biscuit joiner along with offering advice on the best biscuit joinery techniques to take your woodworking skills to a new level.

Best Biscuit Joinery Techniques & Tips

Using a biscuit joiner for most woodworking projects is easy. All you have to do is cut slots, pour some glue, fit in a biscuit and clamp. However, most woodworkers understand that only the best biscuit joining techniques can result in a masterpiece worthy of praise.

 There are quite a handful of approaches when it comes to joining two pieces of wood to design a project. However different biscuit joinery techniques work in different ways to produce stronger and better looking joints.

1.  Check The Depth Of The Cut

best biscuit joinery techniques

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A typical biscuit joiner can easily cut a slot that is almost 0.03 inch deeper than the size of the biscuit in use. Making sure that that there is some room for the use of glue, 0.03 inch remains the perfect depth for most cuts.
Wondering why the depth of the cut plays an important role? To begin with, a cut too deep can mean that the biscuits are far too embedded on singular pieces and will lack strength and holding power. Whereas, if the cut is too shallow, the biscuit will either not fit or won't have enough space to fit in the glue.

 The best biscuit joinery techniques to monitor the depth of your cuts is simply by testing:
  • Mill a slot in a piece of scrap wood
  • Insert a piece of biscuit into the newly created slot
  • Continue to tap in the biscuit; until the bottom is out
  • Draw a line where the biscuit joins the scrap wood
  • Remove the biscuit, plug in the opposite edge in the slow and draw another line
 Conclusion: Ideally, the first line that you have created should appear as hidden inside the biscuit slot. However, if the line is very visible, this indicates that the cut is too shallow. For biscuit joiners producing cuts that way too shallow or deep, we recommend that you reach out for their manual and follow the instruction on re-adjusting the depth on the cut on your particular machine.

2.  Understand The Basics Of Gluing

best biscuit joinery techniques

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It is imperative to use a lot of glue in the joint when using biscuits because biscuits absorb glue, which makes them swell giving them strength and a snug fit. If you do not get enough glue into the joint, you may end up with a joint that is susceptible to failure and imbalance.

There are several ways to get enough glue into the joint. You can place the glue on the tip of the hole and squeeze in the glue, but it may end up being a little messy. You can buy a special glue bottle that fits into the glue slot and gives you a full amount of glue to cover the gap. This works absolutely flawless.

Alternatively, you can also use a flux brush (available in hardware stores or woodworks stores) and a regular bottle of glue. The Flux brush divides the glue evenly within the opening by getting it into the walls where the biscuit can be covered. Also apply glue on each side to ensure maximum coverage. Here is a compromise: too much glue and you have a mess at your hands. A very small amount of glue and you will have a starved joint. Which is just as bad. This can happen quick, so quick that you lose the ability to make side adjustments.

 The general rule of thumb is to put in a bit more glue to guarantee a stronger joint. Choose an adhesive that has a slightly more open time for biscuits to be assembled, especially for a complex assembly. As much as everyone hates to clean up wasted glue, an uglier situation is when you have to scrap a project because of weaker joints.

3.  Choose The Right Biscuit Size

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It is important for you to consider the size of biscuits they use for their application. The general rule is simple here; use the maximum possible biscuit size for your project. Most often we use the largest overall size; # 20. Occasionally, if working with a thinner or narrower material, reduce it to # 10 or # 0.

For small joints, use FF biscuits. These are sufficient for small frames or smaller boxes. For most carpenters, the three of the most common biscuits are # 20, # 10, and # 0. Some also cut slots for the FF biscuit, but then a blade change is necessary because the FF cookie profile is more rounded than oval shaped and requires a smaller blade.

 When using biscuit # 20 and if experiencing fitment issues, shave off the protruding edges of the biscuit to make it sit flush. For example, this may be possible in smaller frames if they are painted (and are therefore concealed in a cushion) or in a narrow box that is covered by a frame. This provides additional strengthening by providing a deeper mechanical fix with the joint.

4.  Prevent Rocking By Using A Fence

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To use or not to use a fence for your woodworking projects is a choice left entirely up to you. However, the use of a fence to safely keep a joint in place and provide you with enough time to carry out your signature gluing routine is highly encouraged.

Most woodworkers already use a fence as reference surface for their projects. If you aren’t frequent with your use of a fence, the following are few important details to note:

Ensure that there is full engagement between your fence and the piece of wood being subjected to the process. Check to see that the work is fastened to the bench, allowing your hands to be completely free and available to control the biscuit joiner.

When using a fence to work on your project, we recommend that your place your biscuit joiner to carefully align with the placement of the biscuit. Set the handle to its highest, slowly lowering it; until the fence is firmly place on the work. Once you’ve achieved a solid placement on the work, locate the detent on fence, position your thumb on it and release the handle to fall right on the work piece. This helps to ensure that the work piece is well placed against the tool. Not that you’ve followed all important protocols, your next step is turn on the power switch, check one time to see that the fence is lying flat against the work piece and thrust the cutter into the material with a steady motion.

 We recommend the use of scrap material, move it in and out when making cuts and test out this technique.

Additional Tips & Best Biscuit Joinery Techniques To Consider

  • Always maintain the cleanliness of your jointer’s blade. This helps prevent overheating and eliminates chances of blunting caused due to the buildup of deposits. Applying on this tip, we also suggest that you avoid using your machine on areas where PVA glue has been applied.
  • Make an L jig when machining biscuit slots into a vertical standing item. This ensures that the work stays in safely in place.
  • Use PVA glue for the most part. This glue works well in a variety of applications such as  with biscuits that have swollen up due to moisture.
  • The easiest way to reset your fence for repetitive jobs is by creating a set of blocks with pre-defined height settings using biscuit slots.
  • Store away your unused biscuits in an airtight jar. This help them remain dry and in their best condition for use.
  •  When gluing two different surfaces facing each other use multiple slots on one edge. This technique makes it easy to align the surfaces and gets the job done precisely and quickly.

The Wrap Up

Undoubtedly, the biscuit joiner is one such tool that has made the lives of most woodworking and carpentry professionals and enthusiasts as easy as ever. However, a large population of woodworkers remain completely unaware of its ability to assist in a wide range of projects. With the help of right techniques to using biscuit joiners you can benefit from its accuracy, high reliability, and potential to enhance your projects.

If you think a biscuit joiner could help you with your woodworking projects, click the button below for more information and prices.

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