Building base cabinets – part 3
In this third installment I’ll detail some of the procedures involved with building base cabinets. The basic concepts are discussed in this issue and there should be enough information and detail so that you can get started building some great base cabinets.
FRAMELESS BASE CABINETS
The basic frameless base cabinet is a box with two sides, called gable ends, a bottom board, back board, and a top rail. There is normally a door, or door and drawer combination, with fixed or adjustable shelving inside the cabinet.
However, all cabinets are not the same width. We often need specific width cabinets to fill dedicated spaces. Here’s a process to use when determining your panel widths for various cabinet sizes.
Standard base cabinets are 36″ high when complete. That height accounts for the cabinet base support and the counter top thickness. For these cabinets I will be using plastic adjustable legs, but you can construct a wood base just as easily.
If, for example, a plan calls for a base cabinet that is 27″ wide with one shelf and two doors, that’s all the information needed to create a cut list. In this example I’ll use ⅝” thick melamine particleboard as the sheet material.
Frameless base cabinets do not need a top board because the counter top covers the cabinet, but they do require an upper rail, so that the door clears the counter top. I usually install a 2″ high rail as shown in the illustration. The height is constant, regardless of the cabinet width, and the rail width is equal to the bottom board’s width.
Cabinet width is always the front dimension. A 27″ wide base cabinet requires a bottom board that’s 23 ⅜” deep by 25 ¾” wide. The 23 3/8″ depth, plus the ⅝” thick back, gives us a standard 24″ deep base cabinet carcase. The 25 ¾” bottom board, plus the thickness of two sides, equals the required cabinet width.
Side boards, or gables, are the same depth as the bottom boards, at 23 ⅜”, and the full height of the finished cabinet carcase is 31″. Cabinet legs, or a fixed base at 4 ¼” high, combine to create a base that’s 35 ¼” high. Adding a ¾” thick counter top gets us to the required 36″ finished height. The back board equals the width and height of the finished cabinet. The adjustable shelf is the same depth as the bottom board and normally 1/16″ narrower in width to permit easy movement in the cabinet.
Door width is found using the 1″ plus formula. To review: the inside cabinet dimension, in the above example at 25 ¾” plus 1″, equals one door width. We need two doors, so dividing 26 ¾” by two, means each door must be 13 ⅜” wide. Door height, on frameless base cabinets, usually equals cabinet carcase height minus 1″, or 30″ total, to allow enough room for counter top overhang.
BUILDING THE FRAMELESS BASE CABINET
Cut the Parts
Cut all the parts, as detailed in your cut list charts, based on the calculations for cabinet widths. The rails for each cabinet are the same width as the bottom board and 2″ high. One rail is needed for each standard full door base cabinet.
Drill holes for the adjustable shelf pins.
Shelf hole spacing is a matter of personal taste, however, I usually space them 1 ¼” on centre.
Apply edge tape
Apply to the exposed edges of the sides, bottom, and underside of the top rail. The easiest tape to apply is heat activated, using an iron. Trim the excess edge tape, after ensuring it is firmly cemented to the board. Use an inexpensive hand trimmer to remove the excess tape on the sides. This task can be accomplished with a sharp file or knife. I’ve had the most success with a hand trimmer available for about $20 in most home stores.
Secure the Sides to the Bottom Board
Use 2″ screws designed for particleboard joinery. The lower edges of the sides are aligned flush with the bottom face of the bottom board. Space the screws about 6″ apart and always pre-drill and counter sink the screw hole.
Attach the Back
Attach with 2″ long PB screws about 6″ apart. Ensure that the back board is flush with the top, back edges of the sides boards, with the bottom edge of the base board, and with the outside edges of the side boards. This board will strengthen and square the cabinet.
Secure the 2″ high rail to the base cabinet. Keep flush with the top edges of the side boards. Install one 2″ long PB screw per side in pre-drilled pilot holes. These screws are close to the edges of the rail and it could split. The common practice, when joining particleboard material, is to keep screws at least 1″ away from a board’s edge. Drive one 2″ screw at the centre point of the rail and secure the back, on each side, with a right angle metal bracket.
Attach Four Adjustable Legs
One per corner, 3 ½” back from the front edge. Secure them with ⅝” long PB screws so that they support the side boards. At one time, these legs were attached with a long bolt through the bottom board. However, many people have opted for the four ⅝” screw method because the legs can be easily moved and cover caps are no longer needed to hide the bolt heads inside the cabinet.
Install Eight Counter Top Brackets
Two per inside face, on the sides, back, and rail board. These are secured with ⅝” PB screws and aligned flush with the cabinet’s top edge.
Edge Tape the Doors With Iron-on Tape
Drill two 35mm holes in each door, ⅛” back from the door edge and 3″ on centre from the bottom and top. These holes will be used to attach the hidden hinges.
Screw the hinges in place with the hinge plates attached. I am using Blum 107° clip-on full overlay hinges on my cabinet. The hinge is properly installed when it’s at 90° to the door’s edge. Use a square to align the hinge when inserting the screws.
Perfect Door Placement Method
It’s easy to guarantee perfect door placement using this simple installation method. First, cut a ⅛” thick spacer. Then, place the door in its normally open position; making sure the vertical alignment is correct. The spacer strip is placed between the door and cabinet side edge. Insert screws through the hinge plate and into the cabinet sideboard. After both hinges are secure, remove the door from the hinge plates and install the screws in the plate that are hidden by the hinge. Re-install the doors and adjust if necessary.
The baseboard can be installed after the cabinet is secured in place. If this cabinet is a stand alone, you should inset the legs 3 ½” on each side. Toe kick board clips are attached to the baseboard. These metal clips slip on the leg shafts and hold the board securely. On stand-alone or end-of run cabinets, where the end of the front toe kick board is exposed, edge tape must be applied. Shelf supports and the shelf can be installed at this point to complete the cabinet.
FACE FRAME BASE CABINETS
The standard face frame base cabinet differs from the standard frameless base because we are adding a wood frame on the front edges in place of edge tape. The panel sizes are also slightly different to account for the thickness, and stile width, of the applied frame.
There are two sides measuring 31″ high. However, the depth of these panels is less because of the frame and because we want to maintain the industry standard depth of 24″. The finished cut size of the sides are 31″ x 22 ⅝”. Adding the thickness of the ⅝” back and the ¾” face frame gives us a total cabinet depth of 24″. Installed standard ¾” thick doors bring the total depth to about 24 ¾”. There is no top board as the kitchen counter top covers the base cabinet. The counter top is secured with screws and right angle clips. This method, along with the face frame, gives the installed base cabinet its strength and rigidity. I use ¾” by ¾” metal right angle clips: two per side, two on the back board, and one in the centre of the face frame rail. The counter top is secured with two ⅝” screws through each right angle clip.
Adjustable cabinet legs are installed, replacing the base frame that was quite common with older style kitchens. Cabinet legs are, in my opinion, one of the positive features that the North American industry has adopted from European cabinetry. The ease of installation, in even the most difficult situations, is remarkable. Most legs adjust from 3 ¾” to 5″ in height. In effect, the kitchen floor would have to be out of level by more than one inch before the legs require shims.
The bottom board determines the inside carcase width and must be cut accurately and squarely. The face frame consists of two stiles and two rails. The stiles are 1″ wide by 31 ¾” long and the rails are 1 ½” high by the interior cabinet dimension width. A standard base door at 30 ½” high is normally mounted with European type hinges in the same fashion as the frameless base.
Base cabinets are multi function units. They are equipped with adjustable shelves, pullout shelf assemblies, drawers, or other special features such as trash and recycling containers. Holes for the adjustable shelves are drilled in the carcase sides by the same method, and with the same jig assembly, as the standard upper cabinets. Drawers and pullouts are easily installed using the European bottom mount drawer glide hardware.
Once again, the most critical step is the accurate cutting of the cabinet parts. The sides must be cut square and to a correct, uniform dimension. The bottom board’s width must be accurate because it determines the inside width of the cabinet. It’s always 2″ narrower than the cabinet exterior on this face frame design. Cabinet width is measured at the widest point on the front of the cabinet. The stiles are each 1″ wide so, if the cabinet we want to build is 30″ wide, our bottom board is 28″ wide. This will make the inside face of each stile flush with the inside face of the cabinet sides. That will allow us to use European hinges.
The stiles are ¾” longer than the cabinet sides. The back board is equal to the cabinets inside dimension plus the two thicknesses of side boards. For a 30″ cabinet, our back board must be 29 ¼” wide when building with ⅝” sheet material.
Standard base cabinets usually have one shelf installed on adjustable pins. The shelves are cut 1/16″ narrower than the bottom boards to make them easier to install and move. As previously detailed, door width is determined by adding 1″ to the interior width. If it’s only one door, that’s the final width. If two doors are needed, divide the interior width plus 1″ formula by two. A 30″ cabinet would need two 14 ½” wide doors mounted on European hidden hinges.
BUILDING THE STANDARD BASE FACE FRAME CABINET
Rip and Cross Cut the Stiles and Rails
Assemble each frame using glue and 2″ long PB screws in counterbored pilot holes. If the screw hole will be visible, in the case of a cabinet at the end of a run, fill the ⅜” counterbore with a wood plug.
You can also use pocket holes, a mortise and tenon joint, dowels, or miniature biscuits to assemble the face frame – the joinery options are many and the choice is yours.
Construct and sand the face frame now and apply two or three coats of finish. Do the finishing while the cabinet carcases are being assembled so they are ready when its time to attach the face frame. Don’t put any finish on the back face of the face frame so that the glue can properly bond.
Cut all the Panels to Size
Follow the same steps discussed when building frameless base cabinets. Omit the top particleboard rail because the face frame top rail takes its place. Remember, panel sizes are slightly different than the frameless base of the same width to account for the face frame. To verify, reference a 30″ base cabinet: you should have a threesided box with inside dimensions of 28″ wide by 30 ⅜” high (the length of the side minus the thickness of the bottom carcase board when using ⅝” sheet material).
Apply to the three carcase edges and place the outside face frame’s top edge flush with the outside top edges of the sideboards. Align the tops of the sideboards with the face frame to match the bottom of your carcase. The face frame should fully cover the carcase edges.
Secure the top corner of the face frame to the carcase body using 2″ finishing nails in pilot holes slightly smaller than the nail thickness. Drill the pilot hole so that it centres, as much as possible, on the PB edge. Secure the other top corner so that the top outside of the face frame is flush with the top outside edge of the carcase. Nail the bottom two corners, making sure the face frame stile’s inside edges are flush with the inside face of the side panels.
Install the remaining nails at 6″ centres, maintaining the alignment. The bottom rail should hang below the cabinet carcase by ¾”. When building with ⅝” thick sheet material, the sides of the face frame should extend ⅜” beyond each side of the carcase and extend ¼” for ¾” thick sheet goods. As well, the inside edge of the bottom rail will be slightly above the bottom board with ⅝” sheets and flush with the top face of the bottom board when using ¾” thick sheet material.
If you don’t like face nailing the frames, use biscuits for an invisible joint. Remember though, the door, in its normally open or closed position, covers the section of the face frame where the nails are located.
Attach Right Angle Brackets
Attach onto the carcase side and back boards as well as the back of the upper face frame rail. Use two brackets per section and secure them with ⅝” long screws. The bracket should be flush, or slightly below, the top edge of each panel so the counter top will be drawn down to the carcase.
The cabinet legs are attached with four ⅝” long screws through the flange. The front legs are set back 3 ½” for a toe kick space. If this cabinet is an end of run unit, open on one side, set back the legs by 3 ½” on that open side as well.
The toe kick board is clipped to the legs with plinth clips that are screwed to the back of the board. The clips allow you to easily install and remove the toe kick board. My kick boards are normally made with the same wood as the doors and face frames.
Drill 35mm Diameter Holes for the Hinges
Drill 3″ on centre from each end of the door, ⅛” away from the door’s edge. Use a hinge-boring bit to drill the hole ½” deep or as specified by the hinge supplier. Install the door following the same steps as detailed for frameless base cabinets.
In the next issue, Danny will give you the building steps for a pantry cabinet. Also in the next issue: a few special cabinets you will need when the standard size doesn’t work.