This story shows you how to repair a casement window.
Casement windows are usually made of wood or metal. The sash is attached to the frame with a hinge. A cranking mechanism called an operator attaches, via an arm, to a channel on the underside of the sash. Once the sash is closed, a latch grabs it and tightens it against the frame.
If a casement is difficult to operate, the solution is often as simple as cleaning and lubricating the gears in the operator or the other moving metal parts. If metal parts are broken, they must be replaced.
If the operator and lock work fine but the window is difficult to close, you may need to scrape and sand away caked paint. If bare wood is binding, then the sash should be planed to make it fit correctly.
Finding replacement parts can be difficult. If you can find the make and model of the unit, you may be able to contact the manufacturer or an online parts supply source to obtain the parts you need.
1 or 2 hours for most repairs
Screwdriver, wire brush
Minor mechanical skills
Place a drop cloth on the floor near the window.
Replacement parts as needed, grease or spray lubricant, cloths for cleaning, an old toothbrush
Remove the operator arm. To get at the arm, you may need to pry off a wooden stop. The operator arm shown disengages by means of a clip. Other types require you to slide the operator arm along the channel until it reaches the access slot. Then you push the arm down and pull it out.