How to Putty a Wooden Sash

Remove Old Putty

• 1

  Scrape away the loose putty with a putty knife. Work the putty knife gently between the glass and the putty to break away the putty from the window and frame. Do not attempt to remove hardened putty by force with the putty knife. This will only cause gouges in the wooden frame or even breaking the window glass.

• 2

  Adjust the heat setting to "medium" on the heat gun. Hold the end of the heat gun 8 inches away from the putty, and move it back and forth across the putty. As the putty softens from the heat, scrape it away with the putty knife. There are metal glazing points under the putty. Avoid bending them as you remove the putty.

• 3

  Continue heating the putty and scraping with the putty knife until all of the putty is off the window and frame. Pry the glazing points away from the wooden sash with the blade of the putty knife. Place the blade between the small ledge of the points and the wooden frame. Pry away from the frame, using the frame as leverage. Carefully remove the glass from the window frame.

Prepare The Sash

• 4

  Scrape away the remaining putty around the wooden sash frame. Some windows use glazing putty on the frame where the glass rests against the inside ledge. Scrape any remaining putty from the glass with a razor knife.

• 5

  Sand the inside of the wooden sash with a medium-grit sandpaper. This removes old paint and smoothes areas around the frame.

• 6

  Apply linseed oil to the wooden sash with a rag. The linseed oil helps prevent the wood from soaking in the oils in the glazing putty. This will keep the new putty soft and pliable.

Apply New Putty

• 7

  Insert a tube of glazing putty into your caulk gun. Apply a 1/8-inch bead of glazing putty to the inside ledge of the wooden sash where the glass sits. Place the glass into the wooden sash and gently press it against the putty with your fingers.

• 8

  Insert new glazing points around the circumference of the sash. Use the putty knife to press the glazing points into the wooden sash without downward pressure over the glass.

• 9

  Squeeze a 1/4-inch bead of glazing putty around the circumference of the glass and wooden sash, much like applying caulk to seal corners.