By the time I purchased my first plate joiner about 15 years ago, these tools had already been used in Europe for 25 years. In 1955, Swiss cabinetmaker and engineer Herman Steiner invented a dado-and-biscuit joining system. Then he founded the Lamello Corporation. Since then, the plate joiner (alias "biscuit joiner," a.k.a. "plate cutter") has become standard equipment for cabinetmakers and finish carpenters. This small tool is worth its weight in glued-up panels because it quickly, simply, and accurately joins stock end-to-end or edge-to-edge. The process of inserting a compressed beechwood "biscuit" at a joint creates an extremely tight union, dooming your doweling jig to gathering dust.
A high-quality plate joiner has good balance, smooth action, a smartly placed trigger, accurate adjustments, and the versatility I need for high-end on-site finish work. I install a lot of maple, alder, and cherry millwork packages on my jobs in Northern California. I need a tool that can travel with me easily and take the punishment of riding in my truck and performing on a busy job site. I tested nine plate joiners, including tools from DeWalt, Freud, Makita, Lamello, Porter-Cable, and Ryobi.
I've heard stories of guys using their joiners as cut-off tools for hardwood floors and for trimming the bottoms of hanging doors, but the most common cuts I make are corner, miter, frame, butt, and center-wall or "T" joints. These types of dadoes require cutting into hardwood ends, edges and crossgrains, so I tested how the tools felt and performed in these applications.
The plate joiners I tested cover the spectrum of prices, and I put each one through the paces I run my own tools through. The goal was to find a tool that performs well, cuts a useful array of biscuit sizes, has ample setting adjustments, a good fence, and balances comfortably on the work--all at a good price.
Power, Vibration, and Noise. Tools in this test batch range from Freud's 5-amp model to Porter-Cable's 7.5-amp machine. They all turned 10,000 rpm with plenty of power for cutting deep slots. Ryobi's little DBJ50 is specifically designed for face-frame joining. It only draws 3.5 amps, runs at 19,000 rpm, and cuts small dadoes easily.
Vibration was minimal throughout the lot, but both Lamello models seem to have an edge in smooth operation. All of the tools I evaluated seem to produce an equal amount of noise.
Balance. When using a joiner, I grip the tool with my right hand and hold the fence against the work with my left hand. This assures me that I am cutting squarely into the stock face. Since my left hand is on the fence, I don't use the upper handle, and have to control the tool with my right hand. The better the tool's weight distribution, the easier it is to get a perfectly square cut.
The Lamello tools have round, comfortable grips and excellent balance. The Freud models are well-balanced, but their large, square bodies are difficult to grip, even for people with large hands. Makita has the balancing act down, but its joiner has an awkward motor-housing protrusion that makes it difficult to grip the tool comfortably. Porter-Cable and DeWalt use smaller grips that provide solid, comfortable control. The Ryobi JM80 employs an aft-grip that sets the motor housing to the front of the tool and makes it nose-heavy. Ryobi's DBJ50 is very lightweight and maneuvers well.
Ease of Use
Fence Adjustment and Alignment. Lamello's and Freud's fences slide freely on rails, but they lock with lever nuts that need to be double-checked for parallel alignment with the blades. The DeWalt, Porter-Cable, and Makita fences move with a quick, accurate gear action. All three tools' fences lock in place with levers. Porter-Cable's large fence and nice slide protrude 3 5/8 inches from the tool for a large, stable work platform. Lamello's unique Step Memory System allows users to change the fence height for another cut, and then recall the previous height with the turn of a dial. This feature works flawlessly, but on a job with several carpenters and various applications I've found it safest to set the fence height and leave it to avoid confusion and inaccuracy. The Memory System is best used where two people share the same tool for different shop applications.
All of the bevel adjustments work by twisting knobs or flipping levers; all are easy to use. Only the Porter-Cable 557 and Ryobi JM80 tools have fences that adjust between 0 and 135 degrees. Freud's JS100A has a fixed fence that stands perpendicular to the face cutter. The Ryobi DBJ50's reversible fence cuts at either 90 or 45 degrees. Other fences adjust from 0 to 90 degrees.
Plunging Action. The Lamello joiners take the prize here. Both tools slide in and out of cuts smoothly, leaving perfect dadoes. The Makita tool also produces a very smooth slide action and an exact cut.
Switch Type. I favor a trigger-like switch mounted on the bottom of the grip. This lets you turn the tool on and off without taking your eyes from the work. The Lamello 101050, DeWalt DW682, Porter-Cable 557, and both Ryobi tools have switches at the bottom of their grips. The Lamello 101250, Makita 3901, and both Freud joiners have thumb switches mounted on the left sides of the tools that are tough for left-handers to operate.
Blade Changing. This would be a more pressing issue if joiner blades had to be changed often. I only switch mine out twice a year, but when the time comes I don't want it to be a hassle. Lamello's and Makita's base plates detach with knobs, but the rest of the tools I tested need wrenches and a screwdriver to do the trick. None of the base plates are problematic to remove, and manufacturers provide the wrenches.
I might change blades more often on Porter-Cable's cutter. You can switch out the 4-inch blade for a 2-inch blade if you're cutting small slots in face frames. This adds a great deal of versatility to the tool.
Dust Pick-Up. These cutters produce shavings rather than fine dust. Collection bags on the tools do a nice job of containment. The Lamello models and the Ryobi DBJ50 do not have dust bags. All of the tools except for the Ryobi DBJ50 have dust ports that hook up to a 1-inch dust collection hose from your shop vac.
Carrying case. Since my tools travel with me, good cases are important. The Lamello 101050 may have the nicest case--a lacquered oak box--but it's too luxurious for the job site. DeWalt's hard plastic case with metal clasp is the best armor against travel and job-site pummeling. Next on the list come the Porter-Cable 557, Makita 3910, and Lamello 101250 cases. Makita's even has a sliding-door compartment for storing biscuits.
The Freud cases are made of very lightweight plastic, but Ryobi's JM80 case reminds me of an old sewing machine box. The top and sides set over the bottom, and it's tough to pile everything in there with one hand and slip the box down with the other. The Ryobi DBJ50 doesn't come with a case.
If money was no object, Lamello's 101050 would top the list. This tool is designed in the European tradition of "built for life." It functions flawlessly and includes the Step Memory System. However, since cost does matter, the Porter-Cable 557 is the best tool for your money. Its large, 0-to-135-degree adjustable fence, plus the additional 2-inch blade for face-frame applications and plenty of power make this an excellent addition to any job site or shop.
DeWalt, Makita, the two Freud tools, and Ryobi's JM80 round out my list of favorites, with a special nod going to Ryobi's little DBJ50.
Mitch Rolicheck is a finish carpenter and woodcarver in Carmichael, Calif.