Milwaukee 5316-21 1-9/16 Spline Rotary Hammer Preview

Milwaukee 5316-21 1-9/16 Spline Rotary Hammer Preview

What is a Spline?

A spline is a piece of wood or other material used to join two pieces together. You may have seen them at home stores where they are sold as “splicing” tools. They come in different lengths and widths, but all are made from one piece of wood with no nails or screws holding it together. When you use these tools to join two pieces together, the splines act like hinges so that when you push down on one side of the joint, it moves up and tightens against the other side. If your joints are too loose, then they will move apart easily and if they are too tight, then they won’t move at all. These types of joints are called “loose”.

Splines are often used to join parts of machines together such as gears, pulleys, and belts. They are also commonly used to join parts of buildings together such as walls and roofs. Splines can be manufactured from various woods including maple, ash, walnut, cherry and many others.

There are also some plastic materials available which make spline manufacture much easier than before.

The most common type of spline is the straight line (or “straight” for short) spline. Many types of joinery involve making a straight groove in one of the pieces and gluing in a straight spline to go into that groove. Before power tools, a spline was a made by hand with adze, chisel and rasps.

Nowadays a table saw or router can be used to cut and shape the spline.

Splines are also called either “male” or “female”. A female spline has a groove that is cut into it and a male spline has a protrusion that fits into that groove. It is important to know which is which when selecting them for a project.

You can also make curved splines which go by several different names including “fish belly”, “s” and “circular”. These types of splines have one flat side and one rounded side. When butted up together they interlock and are very strong.

You can make curved splines on the bandsaw or by using a specialized “spline cutter” bit in your router.

A “bullnose” spline is made by cutting a chamfer onto one long side of a spline. This type of spline doesn’t really interlock in the same way as the other types but can be used in similar ways such as the edge of a table.

Other types of joinery involving splines are “miter” and “tongue and groove”. These types are used to make boxes where each piece is butted up against the next in a tight joint. They can also be used to make roofing tiles where each piece has a groove to interlock with the next.

If you want to build something that looks like traditional joinery but is actually very easy to make, then you can use a spline.

You can cut your own stock to length from a tree. You then need to prepare it for use by cutting out the center of each piece with a router and then sanding it smooth.

Milwaukee 5316-21 1-9/16 Spline Rotary Hammer Preview - Image

Finish your project by staining or painting it.

Here are some examples of projects you can make:


Making a picture frame.

Making a picture frame is as simple as making a box. You need to make the pieces wide enough so that you have a border at the top, bottom and sides for attaching the backing, front and sides of the frame. The inner part can be cut narrower to leave the desired amount of space for your picture.

You can make a simple frame like this one below.

Or you can make one with decorative moulding on the outside like this Victorian style frame:

Making a box.

The simplest type of box is a cube. Its made by making six pieces of stock of equal length (or as close to equal as you can get). Each piece will form one side of the box.

But that’s pretty boring so lets look at some rectanges.

By cutting just two of the pieces of stock at different lengths and butting them up next to each other you can make a rectangular box like this:

You can make fancier looking boxes by making cuts and moldings in the ends of the pieces of stock. For example, this is a “half lap” joint:

Milwaukee 5316-21 1-9/16 Spline Rotary Hammer Preview at

You can cut a “tailed” joint where one piece has two tails that stick out:

Or you can cut a “stile and rail” joint which has a stile and a rail. The stile typically has smaller dimension than the rail and often has some sort of design or molding cut into it. The rail has a long, straight edge.

Here’s an example of a box with this type of joint:

You can improvise and use your imagination to come up with different types of joints.

Glue and nail the box together. You could also use a brad nailer or a pneumatic pin nailer if you have one.

Sand everything. The final result will have a very smooth finish provided that you took your time in the earlier steps. Using a palm sander would make this process go faster.

Making boxes with curved ends.

You can use the same techniques shown above to make boxes with curved ends as in this example:

Or, make boxes with a series of small splines (trimmed down or full size) that run along each corner and near the center of each side. This will give your box a very strong corner system. You can make the splines stick out on the inside or outside of the box.

They can be cut from a single piece of stock, or multiple pieces of stock.

The easiest type to construct is one that uses a single piece of stock cut into three parts (a top and a bottom with a spline in the middle). This type is very easy to make but it might require you to cut a lot of splines (and hence a lot of extra sanding). Here’s an example:

This type is a little more complex than the one shown above. It uses three pieces of stock (a top, bottom and spline in the middle). The only cutting that needs to be done is on the spline which needs to be split down the middle and have half of it flipped over.

Here’s an example:

Milwaukee 5316-21 1-9/16 Spline Rotary Hammer Preview - Image

Making boxes with legs.

You can add legs to your box in order to make it taller. But if you want to keep the cost down you can just make them short so they aren’t as noticeable. The feet can be made any size that you like.

Here’s an example where I made them in a simple design:

Making boxes with small drawers.

You can add small drawers to any of the boxes shown above. The simplest boxes have a “divergent” design like this one:

Or you can make the base wider and have a single drawer that pulls out. This type is very practical if you plan on storing anything in it because the items will be better secured from falling out:

Making boxes with hinged lids.

You can make boxes with hinged lids but it’s a little more complicated than the other examples shown so far. It requires the use of “saddles” which are the little pieces that the hinges are attached to. Using these provides a more professional finish to your box.

The first step is cutting your wood and making all of the pieces. Then, you have to cut the slots for the hinges and the saddles. The slots for the hinges are made first.

The hinges should only be a little longer than the total width of the box so they aren’t visible on the outside when the lid is closed. Mark where you want the hinges and then drill a hole for the screw that attaches it to the lid. Next, you have to notch the areas that will go over the hinge.

The best way to notch the “saddle” area is to clamp a straight edge onto the piece and then score the wood lightly several times in a row with a knife. When you flip the piece over and look at it, you’ll see a very shallow V shaped groove where the saddle will sit. Do this for both sides.

The next step is to place the hinges on the box and make sure they are oriented in the correct direction (so the lid will open). Once that’s done, you can use a straight edge to draw the lines for the saddles onto the wood. You can also drill pilot holes for the screws that will hold the saddles in place at this point.

Once that’s done you can cut out the saddles and attach them to the box. Last but not least you have to notch the lid so it can hinge open. This is very similar to what you did with the saddle area of the box.

Sources & references used in this article: