Joining with dowels - advantages and disadvantages

The dowel joint is the most common joint used in the construction of wooden furniture or derived boards. In the past it was much more common, gradually being replaced by screws and modern fastening systems. However, it is used by DIY enthusiasts as well as by manufacturers of derived board furniture to strengthen and stiffen joints. It is also used by those who don't want to use nails or screws for joints, but are not as skilled or don't have the time to make joints as swallowtail or similar, much more complicated and where much more experience is needed. The joint is not very durable, however, which is why many people do not recommend it. But combined with other systems it helps to increase the strength of the object.

What are dowels? When is this joint used?

Fingerboards are thin wooden cylinders of various diameters and lengths, usually with striations along their length, made from different types of wood. They are also called onions/ceps or tipli. Basically a small wooden rod joining two pieces of wood or board. The dowels can be made by the person making the joint, but are most often bought, being cheap and available in various sizes. Hardwood species are used to make them, especially fag. If the joint is also for aesthetic purposes, wooden dowels in a different colour from the furniture can be used. Several dowels are used to make the joint as strong as possible.

The dowel joint can be used to make joints along the length of the piece or at an angle of 90º or 45º. It is very important that the parts that are joined using dowels are in full contact, otherwise the joint will not hold.

The dowel joint can be hidden or visible. If it is visible, it can contribute to the aesthetic appearance of the resulting object. It can be removable or fixed. If adhesive is used to fix the dowels, the joint will become non-removable. This is the most commonly used option because it is more durable. Without adhesive the joint is not very strong and can only be used for work that will not be subject to high forces.

Modes of implementation

Although it is the simplest joint that does not involve nails or screws, it is not simple for a beginner to make. Joining the two pieces is done by putting the dowel into the holes drilled in the pieces so that they come into perfect contact. This is precisely the weight. To make a perfect joint a few rules must be followed:

• The drill bit with which the holes are drilled should be chosen so that the dowels are slightly forced in and there is no play. If they go in very hard, being much larger than the hole, there is a risk that the plate will crack;
• the depth of the hole in the wood or board should be slightly more than half the length of the dowel so that when they are put together the joint is perfect;
• the cellular axis of the holes must be perfectly parallel to that of the dowel in such a way that the dowel fits perfectly without being stressed and thus loosening the joint;
• Before making the holes, the pieces are placed side by side in the position where they are to be attached and pencil marks are made. This avoids joints where one of the pieces sticks out a few millimetres.
• the dowels must be forced into the holes. They must be hammered in. It is better if the hammer is wooden so that the force is not too great and the board or wood cracks;
• dowels are initially put into holes without adhesive to check that the joint is perfect. The joint is then carefully loosened, adhesive is applied to the dowels and the parts are reassembled.

In the case of visible joints the hole pierces the plate. The finger comes out on the other side of the plate and must be cut flush. After cutting, it is sanded to a fine, smooth finish.

In the past, making such a joint required repeated measurements in order to drill the holes exactly in the desired place and thus have perfect joints. Now there are systems that make the job much easier. There are stop drills that allow you to set the depth to which they penetrate the wood, devices that clamp onto the piece to give perfectly straight holes, or pointers with which you mark the second piece after the first has been drilled so that the pieces are perfectly joined. All this makes joining accessible even to a beginner. However, if you are such a beginner, before you make a joint it is best to get your hands on two pieces of wood or board. You will discover the difficult parts and it will be much easier to make the perfect object afterwards.

Advantages of joining

Although considered by some to be weak, simple and unspectacular, the combination has some not inconsiderable advantages:

• can be done quite simply and quickly with a drill, a suitable drill bit, dowels (bought very cheaply) and wood glue;
• does not need screws or nails;
• can be used at home, even by beginners, to repair wooden household items;
• Aesthetic joints can be achieved without effort or very deep carpentry knowledge;
• it's a durable enough joint you can rely on;
• is stronger than a joint made only with nails or ordinary wood glue;
• help to strengthen and stiffen joints in derived plates alongside other fastening systems;
• very suitable for putting parts together at a 90º angle or in an extension to be securely clamped and with other systems.

Disadvantages

As mentioned above, the joint is considered by many spacers in the field to be weak and mostly suitable for beginners and household chores. Some such assessments are perhaps subjective and pretentious. There are, however, disadvantages that should be taken into account:

• is weaker compared to the widely used plug and socket joint and takes longer to complete;
• without aiding systems can be difficult for someone less experienced. Imperfect joints are much less resistant;
• dowels may fail over time and should be replaced. If there are more, their strength over time is greater;
• humidity variation can lead to dimensional decrease of the dowels. Combined with ageing of the adhesive for various reasons (temperature, unsuitable conditions, unsuitable adhesive for the existing conditions), this leads to play and ultimately to joint failure.

The joint that can help a lot in the household

In industry it is almost always used in conjunction with other clamping systems. But in the household it can be a very good solution for repairing or obtaining objects. We have also used them when we bank repair that was converted for use in the yard, and when we did reclaimed wood tabletop. The items are holding up and have not needed repairs.

Joining with dowels can also help to make decorative objects. Using dowels of exotic woods in dark colours can make the repaired object more attractive. Find these dowels in specialist shops. Good luck!