A friend of mine asked me last month about how to make dado cuts, so I promised him I would show him how to do it in my workshop. Tagging him along to my workshop, I introduced him to the world of dado making using different tools. He surely benefited from my tutorials, and I would likewise want to share with you what I taught him. But what is a dado cut?
Dado cutting involves the adding of a groove to a stock. You will find dado cuts very helpful in woodworking, especially if you create door panels and hold drawer bottoms. Dado grooves also come in handy when you need a slot in the stock.
Dado can also become functional when connecting two pieces of wood. You can cut a dado in one wood piece to snugly fit another wood on that dado cut. Moreover, when making a shelf, you can cut a dado on the shelf’s vertical part to fit the shelf’s horizontal part.
Most Effective Methods for Making Dado Cuts
If you are desirous of cutting dadoes, you got a couple of ways to cut one. For example, you can create a dado groove easily using a router, or a table saw. The table saw is usually the more common tool used for making dado. But you need to install a special dado blade on your table saw to make it functional for cutting dadoes. Here’s a rundown of the different methods you can use to cut dadoes:
1) Cut a Dado Using a Table Saw
You can use a stacked dado head cutter with the table saw. Such a dado head cutter is perfect for cutting dadoes. This blade is usually 8-inch in diameter with a kerf of 1/8″ thick and chippers of 1/8” and 1/16″. You can create a dado with a width ranging between 1/4″ and 3/4″ wide by simply removing or adding chippers. If you wish to make wider dadoes, you should make more than one pass through your saw.
Before installing a stacked dado head, you need to check your tool’s manual to determine if it can accommodate a stacked dado set. You must not try to use this stacked dado head using your circular saw, for it is not appropriate for circular saws and is very dangerous. The stacked dado set also features different blade thicknesses to allow you to vary the dado’s width you are going to make.
You can also use a wobble dado set that consists of a single blade mounted on a spindle (adjustable). You can adjust the blade’s angle to vary the dado’s width. It may be a cheaper alternative, yet the results are less satisfying than stacked dado. Moreover, the risk involved in using wobble blades is higher. Nevertheless, if you have money, it is better to invest in a quality stacked dado set.
One advantage of using the wobble-style dado blade is that it can cut a dado groove that features a rounded bottom. One of its drawbacks is that it produces unnecessary vibration to the table saw.
2) Cutting a Dado Using a Router
Besides the use of the table saw, you can also use a router to cut dadoes. You can utilize a straight-cutting router bit to do it. It will help keep the low the bit speed and make dado using several shallow passes of the bit from 1/16″ to 1/8″ deeper for every pass. In doing so, you can avoid burns on the wood and dulling quickly the router bit.
To ensure that you get a straight dado cut, you can use a straightedge as a guide. If you use a 3/4 thick router bit, for example, you will end up cutting a dado that is a bit wider than a 3/4-inch wood. To avoid such a predicament, you can use a 1/2″ router bit and make two passes to get the desired thickness result.
3) Cutting Dado by Hand
Another method of cutting dado is by hand using several tools like a backsaw, a marking knife, and a couple of chisels. Cutting by hand, of course, offers you a satisfying and personal way of cutting dadoes. At the onset, it will be good to score the layout lines using a marking knife. This scored line can serve as a starting line for your chisel or saw cuts.
You can use the mating workpiece to size up the dado width. Your layout, moreover, should be precise, for it will serve as your guide throughout all your cuts. So, besides the top shoulders, you should also mark the baseline and the edge shoulders.
You can then start making shallow cuts on the long shoulders once you have completed the precise layout. It will also help if you use a guide fence that is clamped to your workpiece. Your cut (down to the baseline) should be consistent and square against your guide. In this way, you will achieve a kerf that is consistent with the layout line.
Take it slow as you inch closer to the baseline while checking how you are doing at both edges. It will be helpful not to overcut through the stock. Once done with the two shoulder cuts, you can use the sharp chisel to clean up the waste. The chisel’s width should be narrower than your dado to give you enough elbow room for cleaning sans digging or chipping much into the shoulders.
The Pros of Dado Cut Joints
Joints come in different varieties, but one of the strongest joints in woodworking is the dado joint. It consists of a three-channel cut across the workpiece’s grain. Then a mating workpiece is fitted into that slot. The dado joints are perfect for bookshelves and cabinets.
Since the dado joints are usually perfectly fitted, they offer optimal resistance to damage or breaking because the workpiece gets captured on all three sides. Compared to the butt joint, it is more robust.
Because of the dado joint’s stability and strength, you will often find this joint in bookcases and cabinets. You will also find it in partitions, drawer dividers, and many other applications. As an aspiring woodworker, you need to know how to make this joint.
Joinery is an important aspect of woodworking, and anyone who wants to dabble in woodworking should learn how to create joinery. Wooden joints should be strong, flexible, rigid, and clean. One of the best form of joinery is the dado joint, and it should be on your priority list of joints to learn as an aspiring woodworker. The dado joint is also called the trench joint or housing joint.
For a start, you will benefit from knowing the abovementioned methods on how to make dado joints using different tools at hand. Once you have mastered how to make the dado joint, you are indeed a step closer to becoming a certified woodworker.