Most shoulder planets are all-metal to help create a heavy, compact tool that can effectively pre-vent or dumpen chatter blade. The blade in an airplane runs across the body width, and the edges and sole of the plane are ground at the perfect angles of each other.
Airplanes come in width from 1/2 "to slightly over an inch. As with a plane block, the blade is mounted bevel-up and generally has an effective angle angle of 37 degrees Another thing that helps in reducing the tip of the grain and making fine cuts in general is an adjustable throat.
In some of these planes it is easy to adapt by way of a screw; Other planes require that you add or remove shims between two parts of the body to change the opening. The blade can be held in place a number of ways. In some larger planes, the blade is often held fast by a lever cover and a locking screw while others use a more traditional bolt bolt with a screwdriver. Smaller planes generally use a wedge and suitably like any plane with wooden floor: You tap on the front or rear of the body to lower or raise the blade.
My general rule of thumb for cutting mortise-and-tenon joints is to take the mortise first and then cut the tenons to fit. If you push the mortise by hand, you'll probably find some variations from the mortise to put on. This means you need to trim or fine-tune each tenon to fit: a perfect job for the shoulder plane. Whenever possible, choose an airplane that is slightly wider than the place you are planning to trim. Make sure to set the airplane for a very good cut and use a razor-sharp razor. As always, get light cuts and make sure to back up the shoulder with a scrap to prevent tear-out.
Bleaching of rabbets is another easy task for a shoulder plane. Place the plane so that its side is firmly on the shoulder of the rabbet's shoulder. Use one shoulder shoulder, as it helps to flatten any high places that can be fitted with a shorter body. Like a wrist, it's important to back up the trailing edge of the rabbet in a scrap to prevent tear-out.
You often hear an airplane referred to as a rabbet plane. That's because it can be used effectively for this task. The disadvantage of using a shoulder plane versus a rabbet plane is that the crooked plane has no built-in guide fence or depth gauge. But one works in a pin as long as you clamp one block of scrap in the work-piece to guide the cut, and check the depth often in a rule. Also, since a shoulder plane does not have a spurs cut off, it is a good idea to write a starting line when putting a crosswise.
Cleaning a dado
Another job I usually assign to an airplane is cleaning grooves or dadoes. Naturally it is best to use a shoulder plane that matches the width of the groove or dado but you can usually get just fine fine to a narrower one as long as you do not check the bottom for the flat often. Keep the edge of the plane pressed firmly against the groove or dodging shoulder as your plane.