Since its inception in 1947, Jigsaw has remained key to cutting arbitrary curves in woods, metals, etc. It consists mainly of a reciprocating blade made of materials such as HSS, HCS, Tungsten carbide, or Diamond grits. Undoubtedly, this tool has helped DIYers and professionals to cut very intricate designs and patterns conveniently.
However, before using a jigsaw, a proper understanding of its specific operation mode and handling is necessary.
Hence, this article aims to shed more light on using the Jigsaw for cutting circles in materials.
Figure 1: A jigsaw with cord.
Table of Contents
1 What is a jigsaw?
Whether you call it a jigsaw, scroll saw, or saber saw, it all means the same thing. Some even refer to the Jigsaw as the “do it all” saw, and the reason is not far-fetched. Its versatility in home arts and craft project is second to none. Furthermore, to avoid injury, a metal guide’s the reciprocating blade direction. A trigger embedded in the handle helps to power the Jigsaw while a selector adjusts the preferred blade speed. They come with either a cord to connect to a power source or without a cord but nickel-cadmium/Lion battery.
Figure 2: An up-close image of Jigsaw showing the base and reciprocating blade.
1.1 What is the use of Jigsaw?
The versatility of jigsaws allows it to maneuver obstructions when cutting the most irregular curves or patterns. Few out of the numerous uses of the Jigsaw includes:
They easily cut curves and other intricate patterns either by freehand or marking-out with a circle jig.
For making straight, bevel, and plunge cuts. By simply adjusting the angle of the blade on the shoe, you can make a bevel cut.
Suitable for cutting an aperture within a board by starting with a drilled hole, e.g., countertops.
Excellent for freehand sawing of materials such as wood, ceramic tile, metal, plastic, laminate, and concrete.
Figure 3: Freehand curved shape cutting.
Figure 4: Bevel cutting in progress.
1.2 Why choose the Jigsaw
To start with, for projects which do not require high precision or accuracy, then you can count on jigsaws. Most importantly, Jigsaw’s ability to cut excellent broad curves with ease makes them a must-have in a workshop. The ease of use, low price, and lightweight set the Jigsaw apart from other saws. These reasons highlighted and many more make the Jigsaw a special type of saw, among others.
2. What is a circle jig?
A circle jig helps to accurately cut circles, semicircles, or irregular arcs with a jigsaw’s aid. The circle jig’s main purpose is to act as a compass or guide to cut curved shapes accurately—the need to cut curved shapes with precise diameter brought about the idea of a circle jig. Unlike straight cuts, precise curved shapes require more than a rip fence for accuracy. Although the approach to constructing a circle jig varies, the base plate remains the main feature of a circle jig.
In this article, the circle jig considered consist of two parts, namely:
1. A jigsaw holder; this consists of a base plate and side anchor, which the Jigsaw mounts on top.
2. A threaded rod and some hex nuts with a galvanized angle to secure all members.
Figure 5: Cutting of intricate design patterns on wood.
3. What do we need to make a circle jig?
The circle jig considered in this article is one that allows for different radius and adjustment. This type of circle jig is arguably the best to have for any project. To create this special type of circle jig, some tools have to be available, such as:
A Drill press/machine to bore holes as required on the base plate and pivot bar
Use a wire saw (wired or cordless) to cut the substrate into a certain shape.
A center punch and drill bit
Use a wrench to pass the screw through the hole.
5/16″ Forstner bit
A 15″-long threaded rod of 3/8’’ diameter
A 1×2 Board
A 1×4 Board
Eight pieces of 3/8 inch. Chrome Hex Nut
A 2 in. x 1-1/2 in. x 1-3/8 inch. Galvanized Angle
Pencil for marking-out
4. How to make a circle jig with a jigsaw?
A circle jig is by far one of the most important accessories needed to enjoy a jigsaw. It becomes especially needed when a circle or curve requires accuracy and precision. Also, this section highlights the sequential steps involved in making a circle jig for yourself.
4.1 Steps Involved in making circle jig with a jigsaw
From observation, using a jigsaw without a circle jig always appear as an arduous task. Hence, in a bid to eliminate such problems, a circle jig becomes pertinent. However, to effectively create a circle jig, follow the sequential step as listed below. In your best interest, endeavor never to jump any of these processes. This video explains how to go about making a circle jig.
4.1.1 Cut the base of the jigsaw holder.
You do this by simply placing your Jigsaw on the 1×4 board to mark-out its base. Afterward, cut to size using the Jigsaw. Note that the board may vary in size based on your Jigsaw’s size.
4.1.2 Prepare the anchoring surface of the Jigsaw Holder.
Start by cutting two pieces of 1×2 boards equivalent to the length of the 1×4 base. Use glue and nailer to join the two pieces together and leave to dry properly.
4.1.3 Drill a hole to fit the blade at the front of the baseboard.
Since the jigsaw blade must pass through the baseboard, then you need to drill a hole. Place the Jigsaw on the baseboard to mark-out the exact location to drill. Use a drill bit that to drill the marked position such that the blade conveniently passes through.
4.1.4 Drill a hole on the Side Anchor of the Jigsaw Holder.
By now, the earlier glued two pieces of 1×2 boards should have dried. Draw a straight line across the base and side anchor board and pair the position on both boards. Ensure that the blade matches the position of the drill point. Use the 3/8″ drill bit to drill through the glue anchor boards. Immediately flip the anchor board and drill with the 5/16″ Forstner bit exactly halfway. Finally, the drilled hole must allow for two pieces of 3/8″ hex nuts through the wood.
4.1.5 Assemble the jigsaw holder
To properly fit the holder to the Jigsaw, use the wood glue in addition to the wood screws. Apply the wood glue to the two pieces of 1×2 boards and attach them to the baseboard. Then drill the holes for the wood screw size you intend using. Finally, screw in place the boards together.
4.1.6 Place two internal hex nuts and fix drilling errors
Firstly, you need to cut the threaded rod to the desired length with a regular hacksaw. On one end of the threaded rod, run the two hex nuts and then tighten with your wrench. Slide the threaded rod completely through the inside of the jigsaw holder.
4.1.7 Creating the anchor point.
Firstly, cut down a 2×2 board to 2 inches and screw-in the galvanized angle to the board. Secondly, use a 3/8″ drill bit capable of drilling wood and metal to drill through the 2×2 and angle. Once the hole is in place, run the threaded rod through the new anchor point. Thirdly, use a long screw to hold down the anchor to the wood you want to cut.
4.1.8 Nuts and bolts.
For all connections made, use two nuts to secure them in place. These two nuts allow for the adjustment (to loosen or tighten) of any member while securing the connection.
4.1.9 Using the Circle jig.
The circle jig is ready to cut the desired shape, which is circular in this case. To avoid mistakes, mount the workpiece on a 2″ Styrofoam and some other 2x4s in a triangular pattern. When entering the contour of the shape, start cutting slowly. Remember always to let the blade do the job and never apply pressure or force. Ensure that the blade, anchor point, and jigsaw holder align perfectly to eliminate any form of mistake. Eventually, it would be best if you had yourself a well-rounded circle for your desired project. To cut other curved shapes, mark-out the outline on the wood and let the circle jig do the rest.
4.2 What should we pay attention to when operating?
From start to finish, when using the Jigsaw for cutting circle, ensure that the assembly remains fitted. Nevertheless, please do not force it through the wood; else, you risk burning and breaking the blade.
5. Can I cut a circle without a router?
Yes, you can cut a circle without a router. From the analysis made above, a jigsaw can carry out this task easily. However, it does this thanks to the circle jig. The circle jig helps to achieve accuracy in cutting circles. While a router appears more prominent for woodwork, jigsaws can cut wood, tiles, granite, concrete, etc. Conversely, routers capable of cutting tiles, granite, and other hard materials are rare and just emerging.
At the end of this article, you should have learned some useful and key knowledge about jigsaws. By now, you should ace your next project involving circle cutting, having learned how to make a circle jig. Over the years, NCCuttingtools has built its capacity and production strength to provide top of the line cutting tool. Reach out to us now to make inquiries and check out our wide array of premium cutting tools.