How to install a wood casement window crank

This installation guide explains how to install the SWISCO right handed crank operator 39-020 (see 39-021 for the opposite side). The SWISCO crank operators 39-020 and 39-021 are designed to accommodate standard screened casement windows 14" to 20" wide employing butt hinges.

Note: 1" minimum clearance between sash and screen is required for arm and channel; 4" is the maximum.

  1. With the window screen panel in position, mark window sill and screen rail at points A and B . Point B is 2-1/4" from with window jamb. Draw a line across the window sill through and beyond points A and B . Remove the screen panel.
  2. Place the window crank operator on this line so that the corners C and D rest on points A and B . Secure the window operator with three screws.
  3. Secure the window crank handle on the operator and turn until the window crank operator's arm touches the closed window.
  4. Slide metal channel guide over the window crank operator's arm button to a point about 1" left of the button. Insert a screw in the first on the left, but do not tighten.
  5. With the button in channel, turn the window crank operator's handle until window is open 90 degrees. Insert a screw in the opposite end of the channel and in the center hole. Tighten all screws.
  6. Notch the window screen rail between the points marked in Step 1 (points A and B ) to a height of 11/16". This notch-out permits screen to fit snugly over operator.
  7. Replace the window screen panel.
All directions on this guide apply only to the right-hand operator. For installation of the left-hand operator, use left jamb of the window sill as base of measurement.
How to install a wood casement window crank
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