The cabinet Parts that matter

Cabinet Boxes & Face Frames

​Materials
Cabinet boxes are made from particle board, MDF or plywood. Solid wood panels normally aren't used to construct the cabinet box except for the face-frame on framed cabinets. Panels made from these wood products are usually covered in either a wood veneer, plastic laminate/melamine or thermofoil.
Stainless steel is another material used to make cabinets though it's much less prevalent than wood. Stainless steel cabinetry provides a novel look and depending on the setting, resembles professional kitchens. On the plus side steel won't expand and contract like wood will in a kitchen environment. One of the down sides is the challenge in keeping the cabinets free from fingerprints which can be tough to clean.

Construction
The cabinet box is essentially just that - a box. The key point to understand here is that there are several methods used to reinforce the box and make sure it remains rigid. One means of reinforcing the cabinet box involves the use of triangular braces in the corners of the box. They're made from either particle board, MDF, plywood, solid wood or plastic. Another reinforcing feature uses an "beam" brace that runs from the front of the box to the rear on the inside of the side panels or along the back from side to side. The beam brace usually fits in a dado slot in the side panel.

Drawers

Materials
Cabinet drawers are predominantly made from the same materials that are used to construct the cabinet cases such as particle board, MDF, plywood and solid wood. On higher quality drawers more of the drawer parts tend to be made of solid wood to stand up the abuse from more frequent opening and closing. On stainless steel cabinets the drawers are made from stainless steel. Some cabinet manufacturers offer options for metal drawers on their wood cabinet lines. These drawers are coated with an epoxy coating.
Drawer fronts, the part of the drawer that you see, tend to be made from solid wood or MDF that's either painted or covered with thermofoil.

Construction
The way a drawer is built plays a large role in its durability and longevity. The drawer box is made up of two side panels, front and back panels and the bottom. Most cabinet drawers have a separate front piece that's attached to the front drawer-box panel although on some drawers the drawer front and front panel are the same piece.
The parts that make up the drawer box can be assembled in several ways. Dovetail joints that are tight form the strongest connection at the corners of the drawer. Doweled joints where one side of the drawer box has dowels installed on one end that fit in holes in the mating panel end is another form of joinery. Drawer bottoms that fit into dado slots in the drawer slides are stronger than bottoms that are just nailed and/or glued to the bottom of the drawer box. Glue, small nails and staples are also used to fasten drawer parts together.

Doors

Materials
Cabinet doors, except for stainless steel cabinets, are made from solid wood or one of the engineered wood products (particle board, MDF, plywood). Engineered wood doors are covered with a wood veneer, laminate or thermofoil.
One of the benefits of MDF is that it can be routed and cut, similar to solid wood, with better results than particle board which is less dense and tends to chip. This feature allows MDF to be formed with a smooth finish to resemble raised-panel doors. The only drawback however is that unlike solid wood, MDF can't be stained (it has no grain) so it has to be painted or covered in thermofoil.

Construction
There are two basic types of cabinet door construction - framed and slab. Framed doors are made up of an outer frame that is built around a panel in the center of the door. The edges of the panel fit into slots milled into the inside edges of the frame and are allowed to "float" within the frame to allow for normal expansion and contraction of the wood. Raised panel doors are a common variety of the frame door style.
Slab doors don't have the separate parts like a framed door and are usually one-piece construction or the combination of several solid pieces of wood glued and joined together to form a solid slab. Slab doors made from plywood or MDF are covered in a veneer, laminate or thermofoil covering.

Shelves

Materials
Cabinet shelves are made from one of the engineered wood products - either plywood, MDF or particle board. Regardless of which material is used they're normally covered with another material such as a wood veneer or laminate ply.

Construction
There really isn't much to a cabinet shelf's construction except for the mention of thickness and whether it's built with a reinforcing rail. Beyond that we're just talking about straight boards made out of one of the materials mentioned above.
Shelf thickness varies based on cabinet manufacturer and the particular product line (often equating to the level of quality) within a certain brand. Shelf thickness ranges from 1/2" to 5/8" to 3/4" thick. Obviously thicker is better when it comes to longer shelves on wide cabinets in order to avoid sag.

The reinforcing rail is an additional strip of wood that's attached to the front edge of a shelf. It provides added rigidity which is especially helpful in avoiding sag, particularly on long shelves. It's a worthwhile feature if you can find it but it's not a prevalent feature on many manufactured cabinets.

​One additional aspect about cabinet shelf construction lies not so much with the shelf itself but how it's held in the cabinet box and whether or not it's adjustable. Shelves are held in place with a variety of hardware that come in different sizes and materials (metal or plastic).