There are two basic types of cabinet: "frameless" cabinets, which are essentially just a box made of plywood or particleboard, and "face frame" cabinets, which have an added wood frame on their front edge. When building face frame cabinets, joining the parts of the face frame together is arguably the most challenging task in the entire process. So, what is the best joinery method for cabinet face frames? There's no shortage of options: pocket screws, mortise and tenon joinery, dowels and biscuits all have their champions. In the end, the choice really depends on your situation and objectives.
For most professional cabinetmakers, the decision to adopt one method or another has to square with a pressing interest in getting cabinets out the door as quickly and efficiently as possible. For the hobbyist, who has much more freedom to experiment, it's a slightly different story. If your livelihood doesn't depend on shaving a few seconds off of this process or that, then the choice really depends on the conditions the cabinets will have to face, your skill level, the equipment you have available, the amount of time you want to give your cabinetry projects, and what you think it takes to join a face frame "right".
Mortise and Tenon Joints
Some cabinetmakers just seem to prefer time-tested joinery methods, and may go to the length of cutting a bona fide mortise and tenon for every face frame joint. There's little doubt that this method is the slowest, but there's also no question that it produces the strongest joint. Many would argue that structurally, a mortise and tenon joint surpasses overkill in this application. But if you're dedicated to making cabinets in the highest possible craft, then the knowledge that you've used the most resilient joint possible may be worth the extra effort.
Of course there are many ways to make a mortise and tenon joint, some being much faster than others. If you're committed to idea of building cabinets suitable for centuries and centuries of use, but prefer to move along as quickly as possible, here are a couple of options to consider.
Quicker, Easier "Loose" Tenon Joints
Arguably every bit as strong as a traditional mortise and tenon joint, a "loose tenon" joint is typically much easier to make. The "loose" in loose tenon joinery simply means that instead of cutting the end of one joint member into the shape of a tenon, a mortise is cut into both parts and then the two are joined by a separate piece of stock. The process is easier because the primary task is simply making two identical mortises, rather than the exacting procedure of cutting a precisely matched mortise and tenon in two separate - often set up-intensive - steps. The loose tenon stock itself can either be purchased ready-made as part of a joinery system, or can be easily made with common woodworking tools.
The affordable BeadLOCK Joinery System is a longtime favorite among weekend woodworkers and produces loose tenon joints easily and fairly quickly. The BeadLOCK system employs a uniquely shaped mortise made up of overlapping drill holes and a matching "ribbed" tenon stock, which is available ready-to-use, or can be made using tenon stock router bits and a router table. The BeadLOCK Jig consists of a multi-holed drill guide and a mechanism for positioning it on the stock so that the BeadLOCK mortise can be reliably and repeatably executed using an ordinary hand drill. Recently redesigned, the BeadLOCK Jig now comes in a Basic and Pro version, both of which can be upgraded with accessory kits that allow greater versatility in mortise/tenon size. A BeadLOCK joint can be made in a fraction of the time that it takes to cut a traditional joint, and many devotees argue that the unique, interlocking shape of the parts actually produces a stronger bond.
The Festool Domino Joinery System also produces a loose tenon joint, and makes the process as slick as it's ever likely to get. The Domino looks similar to a biscuit joiner, and produces joints about as fast, but the similarity between the two tools ends there. Instead of cutting a thin slit into the stock, the Domino uses an oscillating carbide cutter to make a mortise wide enough to house one of the system's specially designed "domino" shaped hardwood tenons. The result is a rock solid joint in record time. Of course all of that speed, strength and precision doesn't come free; the Domino's price tag isn't exactly for the faint of heart. But if you plan on being in the cabinetmaking game for a while, like to speed along as quickly as possible, and prefer a joinery method that will leave no questions about the integrity of your face frame joints, the system is impossible to beat.
While the Domino is definitely not to be confused with a biscuit joiner, that doesn't mean that a biscuit joiner can't be used to join face frames. In fact, the Porter Cable Deluxe Biscuit Joiner comes standard with a second, smaller cutter designed specifically for the task of cutting biscuit slots in 1-1/2" face frame stock. In terms of strength, a biscuit joint is no match for any type of mortise and tenon joint - loose or otherwise. But many cabinetmakers find that fact to be simply beside the point. When you get right down to it, a face frame joint really doesn't have to stand up to a whole lot of stress. Once it's attached to the cabinet box, it simply has to remain stuck together. And we'd guess the majority of cabinetmakers would deem a biscuit joint more than equal to the task.
Faster Still - Pocket Screw Joints
Still more cabinetmakers swear by pocket hole joinery for joining face frames. Pocket hole joinery is used widely in the cabinetmaking industry, and by all accounts is the clear winner when it comes to getting through the face frame assembly process fast. A pocket hole joint doesn't require clamping, but instead comes complete with its very own permanently installed clamp - i.e., the screw. That means that once its assembled, a face frame joined with pocket screws is ready for the next stage in the process, and can be joined to the cabinet box without further ado. Fast, strong and self-contained, pocket hole joinery appears almost tailor-made for face frame joinery, where joint stress is low, and a visible fastener on one side of the finished product is not a problem.
For the hobbyist, the name Kreg has become synonymous with affordable, easy to master pocket hole joinery systems. Over the years, Kreg has continued to improve its groundbreaking jig, and now offers a number of kits. Starting at under and ranging up to around 0 for the K3 Master System, Kreg jigs are available for virtually every woodworking budget. And later, when you turn pro, the semi-automatic Kreg Foreman will bring you up to industry production speed.
More Options...
Still other cabinetmakers prefer to dowel their face frame joints. Nothing wrong with that: Dowel joints have been around for hundreds of years, are more than strong enough for a face frame and - provided you already own a hand drill - require only a modest investment in a doweling jig and few dowels.
A Side Benefit - Learning New Skills
None of the joinery methods mentioned here are limited to face frame assembly, of course. All can be used in a wide variety of woodworking situations. In other words, buying the equipment necessary to try one or more on a specific project involves very little risk - if it turns not to be the preferred method in one situation, you will, without a doubt, find a use for your newly acquired joinery technique somewhere else.