A jigsaw is a handheld power tool that can make curved and straight cuts on different materials, such as wood, metal, plastic, and tile. A jigsaw consists of a motor, a base, and a blade that moves up and down at high speed. A jigsaw is a versatile and useful tool for various woodworking and DIY projects, but it also has some limitations and challenges. One of the common problems that jigsaw users face is splintering, which is when the material breaks or tears along the cut edge, creating an uneven and rough surface. Splintering can ruin the appearance and quality of your workpiece, and it can also cause injuries if you touch the sharp edges.
One of the ways to prevent or reduce splintering is to use the jigsaw upside down. This means that you flip the jigsaw over and cut from the bottom of the material, instead of from the top. This technique has some advantages and disadvantages, and it is not suitable for every situation. In this article, we will explain why people use jigsaw upside down, how to do it properly, and what factors you need to consider before you try it.
The Benefits of Using Jigsaw Upside Down
The main benefit of using jigsaw upside down is that it can minimize splintering, especially on materials that have a veneer, laminate, or coating on the top surface. These materials are prone to splintering because the jigsaw blade cuts through the top layer first, and then pushes the fibers of the lower layer away from the cut edge. This creates a gap between the layers, and the top layer can chip off or peel off easily.
When you use the jigsaw upside down, you reverse the direction of the cut, and the blade cuts through the lower layer first, and then pulls the fibers of the top layer towards the cut edge. This creates a tight bond between the layers, and the top layer can stay intact and smooth. This technique can also produce a cleaner and more accurate cut, as you can see the cut line better from the bottom of the material, and you can follow it more closely with the jigsaw.
Another benefit of using jigsaw upside down is that it can extend the life of your jigsaw blade, as the blade will encounter less resistance and friction from the material. This can also reduce the heat and noise generated by the jigsaw, and make the cutting process more comfortable and efficient.
The Drawbacks of Using Jigsaw Upside Down
While using jigsaw upside down has some advantages, it also has some drawbacks and risks that you need to be aware of. One of the drawbacks is that it can be more difficult and dangerous to use the jigsaw upside down, as you have to hold the jigsaw in an awkward and unnatural position, and you have to deal with the weight and vibration of the jigsaw. This can cause fatigue, strain, and loss of control, and it can increase the chances of accidents and injuries. You also have to be careful not to touch the blade or the cut edge, as they can be very hot and sharp.
Another drawback of using jigsaw upside down is that it can damage the base of your jigsaw, as the base will rub against the material and the work surface. This can scratch, dent, or bend the base, and affect the stability and alignment of the jigsaw. You can prevent this by covering the base with masking tape or painter’s tape, or by using a special base plate that is designed for upside down cutting.
A third drawback of using jigsaw upside down is that it can limit the types and shapes of cuts you can make, as you have to cut from the edge of the material, and you cannot make plunge cuts or internal cuts. You also have to make sure that the material is thin and flexible enough to bend over the edge of the work surface, and that the work surface is strong and stable enough to support the material and the jigsaw. You cannot use this technique on thick, rigid, or fragile materials, as they can crack or break under the pressure of the jigsaw.
How to Use Jigsaw Upside Down Properly
If you decide to use jigsaw upside down, you need to follow some steps and precautions to do it properly and safely. Here are some tips to help you:
Choose the right blade for the material and the cut. You need to use a blade that is sharp, durable, and suitable for the thickness and density of the material. You also need to use a blade that has a reverse tooth configuration, which means that the teeth point downwards instead of upwards. This will ensure that the blade cuts on the downstroke, and not on the upstroke, and that the blade pulls the material towards the cut edge, and not away from it.
Mark the cut line on the bottom of the material. You can use a pencil, a ruler, a tape measure, or a compass to draw the cut line. If you want to make a curved cut, you can use a flexible curve ruler or a string to mark the curve. You can also transfer the cut line from the top of the material to the bottom of the material, by using a drill or a nail to make small holes along the cut line, and then connecting the holes with a pencil or a marker.
Clamp the material to the work surface, with the bottom side facing up and the cut line overhanging the edge of the work surface. Make sure the material is flat and secure, and the cut line is accessible and visible. You can also apply masking tape or painter’s tape along the cut line on both sides of the material, to reduce splintering and tear-out.
Insert the blade into the jigsaw and adjust the speed and orbital settings. The speed setting controls how fast the blade moves up and down, and the orbital setting controls how much the blade moves forward and backward. For upside down cutting, you need to use a low speed and a low orbital setting, as this will produce a smoother and more precise cut.
Start the jigsaw and let the blade reach full speed before touching the material. Align the blade with the cut line and gently press the jigsaw against the material. Do not force the jigsaw or push it too hard, as this will cause the blade to bend or wander off the cut line. Let the blade do the work and guide the jigsaw along the cut line with a steady hand.
Follow the curve of the cut line as closely as possible. If you need to make a sharp turn, stop the jigsaw and reposition it before continuing the cut. Do not twist or tilt the jigsaw, as this will cause the blade to bind or break. Keep the jigsaw base flat and parallel to the material at all times.
Cut slowly and carefully, especially near the end of the cut. Do not rush or jerk the jigsaw, as this will cause the material to splinter or crack. Support the material with your free hand or another clamp to prevent it from falling or breaking. When you finish the cut, turn off the jigsaw and remove the blade from the material.
Conclusion
Using jigsaw upside down is a technique that can help you prevent or reduce splintering, especially on materials that have a veneer, laminate, or coating on the top surface. However, this technique also has some drawbacks and risks, and it is not suitable for every situation. You need to weigh the pros and cons of using jigsaw upside down, and follow the proper steps and precautions to do it safely and effectively. A jigsaw is a powerful and handy tool that can help you with various woodworking and DIY projects, but you also need to use it wisely and responsibly. We hope this article has helped you understand why people use jigsaw upside down and how to do it yourself. Happy cutting!