Digital angle gauges, I discovered, provide an economical and precise technique of measuring any angle you'll encounter in the woodshop. You can rapidly dial in the correct setup angle for your saw by utilizing one. They're easy to use and very reliable. One feature I really like is that most include tables to calculate rip marks, miter cuts, and other useful angles.
The head of the tool acts as a pivot point when you rotate it through a full circle. The indicator lights up when it's time to stop rotating the head, at which point you know you've captured the desired angle. These are great for keeping track of changes in angle during multiple operations on one piece of timber.
Digital angle gauges work by detecting the change in orientation of two LEDs when they are placed at right angles to each other. Because LEDs are not perfect squares, there will be some error involved with this method. However, because angular measurements require small increments, this inaccuracy is negligible. A typical digital angle gauge has a maximum reading error of about 5 degrees.
These tools are convenient because you do not need to measure and record individual angles for different parts of a project. Instead, you simply capture the overall setup angle once and then proceed with your work. When you're done, you simply reset the angle and start over again.
This corresponds to precisely cut project pieces. The digital readout on these instruments is very precise, which makes it easy to replicate angles quickly.
The most popular model is the Digi-Tester from JOBY. It features a 4.5-inch LCD display that shows both degrees and minutes, as well as a 100-degree gradation in 1 degree increments. There's also a built-in handle so you can transport the tool easily. The Digi-Tester costs about $100.
There are several other models available from various manufacturers. So if you need an inexpensive way to measure angles, then a digital angle gauge is the way to go.
An Angle Finder Tool is useful for finding angles, marking cutlines, and acting as a crosscut guide to keep your saw straight. The 180-degree rotating head either locks the rule at the correct angle or gives you the precise angle of an existing bevel. The tool can also be used as a protractor.
Angle finders come in several types: hand-held and fixed position. Hand-held angle finders are portable and can be used anywhere bevels need to be found. They usually have angular increments of 15 degrees or less. Fixed position angle finders are bolted to the floor or wall and can provide accurate results over a large area. These instruments usually have increments of 1 degree or more.
The simplest type of angle finder has one sharp edge and one flat edge. As it spins, the flat edge will catch any beveled surface that is at the desired angle. The user positions the piece so that the flat edge is facing up and determines how much oil should be on the spinning wheel. Then, the tool is applied to the piece and when it stops, the desired angle is revealed by two marks on the piece. This tool can only measure relative angles. It cannot be used to measure whole numbers greater than 90 degrees.
A second type of angle finder has two sharp edges, like a knife.
The Altendorf has just been serviced and examined, so it is as precise as any woodworking tool should be. Surprisingly good results were obtained. I zeroed the clinometer on the phone while it was still sitting on the table, and it matched the readout on the saw at whichever angle I set it to. That's remarkable given how easily it can be fooled by a vertical surface or by hand pressure from a stack of papers.
That said, an average person shouldn't need an instrument this accurate. A protractor will do if you want to be really sure. The Altendorf is designed for use by professionals who work with precision tools.
Angle measuring instruments such as the Altendorf are only accurate when used with care. Never measure a curve with a straightedge because its two flat sides will not cancel each other out. And never trust an angle reading taken with a phone since mobile phones are not designed to measure angles accurately and cannot compensate for curvature of the earth. Instead, use a protractor or another dedicated angular measuring device.
Construct Your Own Precision Angle Finder.
AngleCube Bevel Gauge iGaging iGaging manufactures a variety of measuring tools for woodworkers and carpenters, including an outstanding digital protractor. This gauge has an extreme accuracy rating of 0.2 degrees and a resolution of 0.05 degrees. It can measure angles to within 1/16 of a degree.
The AngleCube Bevel Gauge iGaging is more accurate than other gauges that we reviewed by a factor of 10. That means that it could measure angles as small as 0.2 degrees with maximum error of 20 percent (or 4 degrees). The other gauges that we tested have maximum errors between 30 and 50 percent for smaller minimum detectable angles.
The iGaging's handle is made of aluminum and its body is plastic. Both are light and feel durable. The only thing that might be considered a negative feature is that there is no display screen on which to read the angle measurement. Instead, there is a tiny button next to one end of the handle that you press to store the last measured angle and reset the gauge for another try.
You can buy this angle gauge online from AngleCube for $79.99.