13 Simple Ways to Improve Accuracy
1. Use Calipers or an Etched Rule
Set your marking gauge using an etched rule or a caliper. Setting the marking gauge freehand can lead to mistakes. With a rule, the cutting wheel sits securely in the etched marking of the rule and the fence is brought up against the end of the rule. You can often get as accurate as 1/64", depending on the type of rule you’re using. With a caliper the cutting wheel is set against the end of one jaw, and the fence is slid until it registers on the end of the other jaw.
2. Check Your Cuts
When setting up machinery, check your test cuts, not just your setup. For a host of reasons, the part that is freshly cut may not be the exact same dimension as the fence width indicates. Always measure twice, cut once, then measure one final time. And just because layout tools indicate the blade is set at 45 degrees to the fence doesn’t necessarily mean that the cut will also be 45 degrees.
3. Saw Notch
Cut V-notches with a marking gauge or knife, followed by a chisel to positively locate your hand saw. This also works with power saws. The side of the V-notch that is on the line will act as a small wall, and will keep the saw blade positioned on the line for the start of the cut. With the V-notch chiseled in, the saw will sit nicely against the knife line.
4. Lipped Drill Bit
When using lipped drill bits, watch to see that the spurs engage evenly around the circumference, indicating that the bit is perpendicular to the material. In this image, the right-hand side of the hole is scored more deeply, indicating that the drill bit was tilted in that direction.
5. Drill Bit Setup
Instead of using scales to measure distances, use setup blocks or other items with known dimensions (drill bits, MDF, etc.). Here, the 9/32" drill bit gently contacts the blade’s tooth when slid along the fence.
6. With/Without Task Lighting
Use magnification and good lighting. Task lighting is great when working in tight on workpieces. After all, if you don’t have enough light to see the details, then how will you make exacting joints and furniture details? Left: ambient shop lighting; right: task lighting.
7. Etched Rule on Edge
When transferring measurements from a rule, stand it on edge so you don’t have to transfer the mark as far. Bringing the scale directly to the wood eliminates parallax. The knife registers securely in the etched markings of the rule.
8. Knife in Knife Line
When extending a line across a workpiece with a square, set your marking tool on the existing mark first, then slide the square up to it (not the other way around). Then, when you’re marking the line, ensure you don’t change the angle of the knife, as that could change the position of the line.
Remove burrs/fuzzies from edges before doing layout. These saw whiskers can get trapped between the workpiece and a tool and prevent layout tools from registering properly.
A carefully made template makes repeatability a breeze. It also makes layout much faster. You don’t often need anything overly fancy or complex to reap any benefits.
Keep your tools clean and sharp at all times. This diamond stone is meant to work, not to look pretty. As soon as tools are dull they perform poorly and can also be more dangerous to work with, as they act unpredictably.
Secure your work properly. It’s far easier to achieve accuracy when things not supposed to move don’t. Clamps, a vise or stops all work perfect for this purpose. Making a saw cut with only your hand securing the workpiece is a great way to be inaccurate, not to mention get yourself injured.
Don’t rush, and take breaks. Being tired, hurried or fatigued increases the chance of mistakes and injury. You have a stool or chair in your shop. Use it. If a short break isn’t enough you will likely be much further ahead by getting a good sleep and picking back up where you were, rather than making a mistake and wasting material and time while increasing frustration.